3 perldiag - various Perl diagnostics
7 These messages are classified as follows (listed in increasing order of
10 (W) A warning (optional).
11 (D) A deprecation (enabled by default).
12 (S) A severe warning (enabled by default).
13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
15 (X) A very fatal error (nontrappable).
16 (A) An alien error message (not generated by Perl).
18 The majority of messages from the first three classifications above
19 (W, D & S) can be controlled using the C<warnings> pragma.
21 If a message can be controlled by the C<warnings> pragma, its warning
22 category is included with the classification letter in the description
23 below. E.g. C<(W closed)> means a warning in the C<closed> category.
25 Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
26 and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
27 to a reference to a routine that will be called on each warning instead
28 of printing it. See L<perlvar>.
30 Severe warnings are always enabled, unless they are explicitly disabled
31 with the C<warnings> pragma or the B<-X> switch.
33 Trappable errors may be trapped using the eval operator. See
34 L<perlfunc/eval>. In almost all cases, warnings may be selectively
35 disabled or promoted to fatal errors using the C<warnings> pragma.
38 The messages are in alphabetical order, without regard to upper or
39 lower-case. Some of these messages are generic. Spots that vary are
40 denoted with a %s or other printf-style escape. These escapes are
41 ignored by the alphabetical order, as are all characters other than
42 letters. To look up your message, just ignore anything that is not a
47 =item accept() on closed socket %s
49 (W closed) You tried to do an accept on a closed socket. Did you forget
50 to check the return value of your socket() call? See
53 =item Aliasing via reference is experimental
55 (S experimental::refaliasing) This warning is emitted if you use
56 a reference constructor on the left-hand side of an assignment to
57 alias one variable to another. Simply suppress the warning if you
58 want to use the feature, but know that in doing so you are taking
59 the risk of using an experimental feature which may change or be
60 removed in a future Perl version:
62 no warnings "experimental::refaliasing";
63 use feature "refaliasing";
66 =item Allocation too large: %x
68 (X) You can't allocate more than 64K on an MS-DOS machine.
70 =item '%c' allowed only after types %s in %s
72 (F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
73 after certain types. See L<perlfunc/pack>.
75 =item Ambiguous call resolved as CORE::%s(), qualify as such or use &
77 (W ambiguous) A subroutine you have declared has the same name as a Perl
78 keyword, and you have used the name without qualification for calling
79 one or the other. Perl decided to call the builtin because the
80 subroutine is not imported.
82 To force interpretation as a subroutine call, either put an ampersand
83 before the subroutine name, or qualify the name with its package.
84 Alternatively, you can import the subroutine (or pretend that it's
85 imported with the C<use subs> pragma).
87 To silently interpret it as the Perl operator, use the C<CORE::> prefix
88 on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
89 to be an object method (see L<perlsub/"Subroutine Attributes"> or
92 =item Ambiguous range in transliteration operator
94 (F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
95 all. To include a C<-> character in a transliteration, put it either
96 first or last. (In the past, C<tr/a-z-0//> was synonymous with
97 C<tr/a-y//>, which was probably not what you would have expected.)
99 =item Ambiguous use of %s resolved as %s
101 (S ambiguous) You said something that may not be interpreted the way
102 you thought. Normally it's pretty easy to disambiguate it by supplying
103 a missing quote, operator, parenthesis pair or declaration.
105 =item Ambiguous use of -%s resolved as -&%s()
107 (S ambiguous) You wrote something like C<-foo>, which might be the
108 string C<"-foo">, or a call to the function C<foo>, negated. If you meant
109 the string, just write C<"-foo">. If you meant the function call,
112 =item Ambiguous use of %c resolved as operator %c
114 (S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
115 bitwise and, and multiplication) I<and> initial special characters
116 (denoting hashes, subroutines and typeglobs), and you said something
117 like C<*foo * foo> that might be interpreted as either of them. We
118 assumed you meant the infix operator, but please try to make it more
119 clear -- in the example given, you might write C<*foo * foo()> if you
120 really meant to multiply a glob by the result of calling a function.
122 =item Ambiguous use of %c{%s} resolved to %c%s
124 (W ambiguous) You wrote something like C<@{foo}>, which might be
125 asking for the variable C<@foo>, or it might be calling a function
126 named foo, and dereferencing it as an array reference. If you wanted
127 the variable, you can just write C<@foo>. If you wanted to call the
128 function, write C<@{foo()}> ... or you could just not have a variable
129 and a function with the same name, and save yourself a lot of trouble.
131 =item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
133 =item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
135 (W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
136 the name of a Perl keyword), which might be looking for element number
137 2 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
138 might have meant to pass an anonymous arrayref to the function named
139 foo, and then do a scalar deref on the value it returns. If you meant
140 that, write C<${foo([2])}>.
142 In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
143 to disambiguate between array subscripts and character classes.
144 C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
145 by the character class C<[2345]>. If an array subscript is what you
146 want, you can avoid the warning by changing C</${length[2345]}/> to the
147 unsightly C</${\$length[2345]}/>, by renaming your array to something
148 that does not coincide with a built-in keyword, or by simply turning
149 off warnings with C<no warnings 'ambiguous';>.
151 =item '|' and '<' may not both be specified on command line
153 (F) An error peculiar to VMS. Perl does its own command line
154 redirection, and found that STDIN was a pipe, and that you also tried to
155 redirect STDIN using '<'. Only one STDIN stream to a customer, please.
157 =item '|' and '>' may not both be specified on command line
159 (F) An error peculiar to VMS. Perl does its own command line
160 redirection, and thinks you tried to redirect stdout both to a file and
161 into a pipe to another command. You need to choose one or the other,
162 though nothing's stopping you from piping into a program or Perl script
163 which 'splits' output into two streams, such as
165 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
172 =item Applying %s to %s will act on scalar(%s)
174 (W misc) The pattern match (C<//>), substitution (C<s///>), and
175 transliteration (C<tr///>) operators work on scalar values. If you apply
176 one of them to an array or a hash, it will convert the array or hash to
177 a scalar value (the length of an array, or the population info of a
178 hash) and then work on that scalar value. This is probably not what
179 you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
182 =item Arg too short for msgsnd
184 (F) msgsnd() requires a string at least as long as sizeof(long).
186 =item Argument "%s" isn't numeric%s
188 (W numeric) The indicated string was fed as an argument to an operator
189 that expected a numeric value instead. If you're fortunate the message
190 will identify which operator was so unfortunate.
192 =item Argument list not closed for PerlIO layer "%s"
194 (W layer) When pushing a layer with arguments onto the Perl I/O
195 system you forgot the ) that closes the argument list. (Layers
196 take care of transforming data between external and internal
197 representations.) Perl stopped parsing the layer list at this
198 point and did not attempt to push this layer. If your program
199 didn't explicitly request the failing operation, it may be the
200 result of the value of the environment variable PERLIO.
202 =item Argument "%s" treated as 0 in increment (++)
204 (W numeric) The indicated string was fed as an argument to the C<++>
205 operator which expects either a number or a string matching
206 C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
207 Auto-decrement> for details.
209 =item assertion botched: %s
211 (X) The malloc package that comes with Perl had an internal failure.
213 =item Assertion %s failed: file "%s", line %d
215 (X) A general assertion failed. The file in question must be examined.
217 =item Assigned value is not a reference
219 (F) You tried to assign something that was not a reference to an lvalue
220 reference (e.g., C<\$x = $y>). If you meant to make $x an alias to $y, use
223 =item Assigned value is not %s reference
225 (F) You tried to assign a reference to a reference constructor, but the
226 two references were not of the same type. You cannot alias a scalar to
227 an array, or an array to a hash; the two types must match.
232 \$x = $y; # error; did you mean \$y?
234 =item Assigning non-zero to $[ is no longer possible
236 (F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
237 the special variable C<$[>, which is deprecated, is now a fixed zero value.
239 =item Assignment to both a list and a scalar
241 (F) If you assign to a conditional operator, the 2nd and 3rd arguments
242 must either both be scalars or both be lists. Otherwise Perl won't
243 know which context to supply to the right side.
245 =item <> at require-statement should be quotes
247 (F) You wrote C<< require <file> >> when you should have written
250 =item Attempt to access disallowed key '%s' in a restricted hash
252 (F) The failing code has attempted to get or set a key which is not in
253 the current set of allowed keys of a restricted hash.
255 =item Attempt to bless into a freed package
257 (F) You wrote C<bless $foo> with one argument after somehow causing
258 the current package to be freed. Perl cannot figure out what to
259 do, so it throws up in hands in despair.
261 =item Attempt to bless into a reference
263 (F) The CLASSNAME argument to the bless() operator is expected to be
264 the name of the package to bless the resulting object into. You've
265 supplied instead a reference to something: perhaps you wrote
271 bless $self, ref($proto) || $proto;
273 If you actually want to bless into the stringified version
274 of the reference supplied, you need to stringify it yourself, for
277 bless $self, "$proto";
279 =item Attempt to clear deleted array
281 (S debugging) An array was assigned to when it was being freed.
282 Freed values are not supposed to be visible to Perl code. This
283 can also happen if XS code calls C<av_clear> from a custom magic
284 callback on the array.
286 =item Attempt to delete disallowed key '%s' from a restricted hash
288 (F) The failing code attempted to delete from a restricted hash a key
289 which is not in its key set.
291 =item Attempt to delete readonly key '%s' from a restricted hash
293 (F) The failing code attempted to delete a key whose value has been
294 declared readonly from a restricted hash.
296 =item Attempt to free non-arena SV: 0x%x
298 (S internal) All SV objects are supposed to be allocated from arenas
299 that will be garbage collected on exit. An SV was discovered to be
300 outside any of those arenas.
302 =item Attempt to free nonexistent shared string '%s'%s
304 (S internal) Perl maintains a reference-counted internal table of
305 strings to optimize the storage and access of hash keys and other
306 strings. This indicates someone tried to decrement the reference count
307 of a string that can no longer be found in the table.
309 =item Attempt to free temp prematurely: SV 0x%x
311 (S debugging) Mortalized values are supposed to be freed by the
312 free_tmps() routine. This indicates that something else is freeing the
313 SV before the free_tmps() routine gets a chance, which means that the
314 free_tmps() routine will be freeing an unreferenced scalar when it does
317 =item Attempt to free unreferenced glob pointers
319 (S internal) The reference counts got screwed up on symbol aliases.
321 =item Attempt to free unreferenced scalar: SV 0x%x
323 (S internal) Perl went to decrement the reference count of a scalar to
324 see if it would go to 0, and discovered that it had already gone to 0
325 earlier, and should have been freed, and in fact, probably was freed.
326 This could indicate that SvREFCNT_dec() was called too many times, or
327 that SvREFCNT_inc() was called too few times, or that the SV was
328 mortalized when it shouldn't have been, or that memory has been
331 =item Attempt to pack pointer to temporary value
333 (W pack) You tried to pass a temporary value (like the result of a
334 function, or a computed expression) to the "p" pack() template. This
335 means the result contains a pointer to a location that could become
336 invalid anytime, even before the end of the current statement. Use
337 literals or global values as arguments to the "p" pack() template to
340 =item Attempt to reload %s aborted.
342 (F) You tried to load a file with C<use> or C<require> that failed to
343 compile once already. Perl will not try to compile this file again
344 unless you delete its entry from %INC. See L<perlfunc/require> and
347 =item Attempt to set length of freed array
349 (W misc) You tried to set the length of an array which has
350 been freed. You can do this by storing a reference to the
351 scalar representing the last index of an array and later
352 assigning through that reference. For example
354 $r = do {my @a; \$#a};
357 =item Attempt to use reference as lvalue in substr
359 (W substr) You supplied a reference as the first argument to substr()
360 used as an lvalue, which is pretty strange. Perhaps you forgot to
361 dereference it first. See L<perlfunc/substr>.
363 =item Attribute "locked" is deprecated
365 (D deprecated) You have used the attributes pragma to modify the
366 "locked" attribute on a code reference. The :locked attribute is
367 obsolete, has had no effect since 5005 threads were removed, and
368 will be removed in a future release of Perl 5.
370 =item Attribute prototype(%s) discards earlier prototype attribute in same sub
372 (W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
373 example. Since each sub can only have one prototype, the earlier
374 declaration(s) are discarded while the last one is applied.
376 =item Attribute "unique" is deprecated
378 (D deprecated) You have used the attributes pragma to modify
379 the "unique" attribute on an array, hash or scalar reference.
380 The :unique attribute has had no effect since Perl 5.8.8, and
381 will be removed in a future release of Perl 5.
383 =item av_reify called on tied array
385 (S debugging) This indicates that something went wrong and Perl got I<very>
386 confused about C<@_> or C<@DB::args> being tied.
388 =item Bad arg length for %s, is %u, should be %d
390 (F) You passed a buffer of the wrong size to one of msgctl(), semctl()
391 or shmctl(). In C parlance, the correct sizes are, respectively,
392 S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
393 S<sizeof(struct shmid_ds *)>.
395 =item Bad evalled substitution pattern
397 (F) You've used the C</e> switch to evaluate the replacement for a
398 substitution, but perl found a syntax error in the code to evaluate,
399 most likely an unexpected right brace '}'.
401 =item Bad filehandle: %s
403 (F) A symbol was passed to something wanting a filehandle, but the
404 symbol has no filehandle associated with it. Perhaps you didn't do an
405 open(), or did it in another package.
407 =item Bad free() ignored
409 (S malloc) An internal routine called free() on something that had never
410 been malloc()ed in the first place. Mandatory, but can be disabled by
411 setting environment variable C<PERL_BADFREE> to 0.
413 This message can be seen quite often with DB_File on systems with "hard"
414 dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
415 which is left unnoticed if C<DB> uses I<forgiving> system malloc().
419 (P) One of the internal hash routines was passed a null HV pointer.
421 =item Badly placed ()'s
423 (A) You've accidentally run your script through B<csh> instead
424 of Perl. Check the #! line, or manually feed your script into
427 =item Bad name after %s
429 (F) You started to name a symbol by using a package prefix, and then
430 didn't finish the symbol. In particular, you can't interpolate outside
439 $sym = "mypack::$var";
441 =item Bad plugin affecting keyword '%s'
443 (F) An extension using the keyword plugin mechanism violated the
446 =item Bad realloc() ignored
448 (S malloc) An internal routine called realloc() on something that
449 had never been malloc()ed in the first place. Mandatory, but can
450 be disabled by setting the environment variable C<PERL_BADFREE> to 1.
452 =item Bad symbol for array
454 (P) An internal request asked to add an array entry to something that
455 wasn't a symbol table entry.
457 =item Bad symbol for dirhandle
459 (P) An internal request asked to add a dirhandle entry to something
460 that wasn't a symbol table entry.
462 =item Bad symbol for filehandle
464 (P) An internal request asked to add a filehandle entry to something
465 that wasn't a symbol table entry.
467 =item Bad symbol for hash
469 (P) An internal request asked to add a hash entry to something that
470 wasn't a symbol table entry.
472 =item Bareword found in conditional
474 (W bareword) The compiler found a bareword where it expected a
475 conditional, which often indicates that an || or && was parsed as part
476 of the last argument of the previous construct, for example:
480 It may also indicate a misspelled constant that has been interpreted as
483 use constant TYPO => 1;
484 if (TYOP) { print "foo" }
486 The C<strict> pragma is useful in avoiding such errors.
488 =item Bareword "%s" not allowed while "strict subs" in use
490 (F) With "strict subs" in use, a bareword is only allowed as a
491 subroutine identifier, in curly brackets or to the left of the "=>"
492 symbol. Perhaps you need to predeclare a subroutine?
494 =item Bareword "%s" refers to nonexistent package
496 (W bareword) You used a qualified bareword of the form C<Foo::>, but the
497 compiler saw no other uses of that namespace before that point. Perhaps
498 you need to predeclare a package?
500 =item BEGIN failed--compilation aborted
502 (F) An untrapped exception was raised while executing a BEGIN
503 subroutine. Compilation stops immediately and the interpreter is
506 =item BEGIN not safe after errors--compilation aborted
508 (F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
509 implies a C<BEGIN {}>) after one or more compilation errors had already
510 occurred. Since the intended environment for the C<BEGIN {}> could not
511 be guaranteed (due to the errors), and since subsequent code likely
512 depends on its correct operation, Perl just gave up.
514 =item \%d better written as $%d
516 (W syntax) Outside of patterns, backreferences live on as variables.
517 The use of backslashes is grandfathered on the right-hand side of a
518 substitution, but stylistically it's better to use the variable form
519 because other Perl programmers will expect it, and it works better if
520 there are more than 9 backreferences.
522 =item Binary number > 0b11111111111111111111111111111111 non-portable
524 (W portable) The binary number you specified is larger than 2**32-1
525 (4294967295) and therefore non-portable between systems. See
526 L<perlport> for more on portability concerns.
528 =item bind() on closed socket %s
530 (W closed) You tried to do a bind on a closed socket. Did you forget to
531 check the return value of your socket() call? See L<perlfunc/bind>.
533 =item binmode() on closed filehandle %s
535 (W unopened) You tried binmode() on a filehandle that was never opened.
536 Check your control flow and number of arguments.
538 =item Bit vector size > 32 non-portable
540 (W portable) Using bit vector sizes larger than 32 is non-portable.
542 =item Bizarre copy of %s
544 (P) Perl detected an attempt to copy an internal value that is not
547 =item Bizarre SvTYPE [%d]
549 (P) When starting a new thread or returning values from a thread, Perl
550 encountered an invalid data type.
552 =item Buffer overflow in prime_env_iter: %s
554 (W internal) A warning peculiar to VMS. While Perl was preparing to
555 iterate over %ENV, it encountered a logical name or symbol definition
556 which was too long, so it was truncated to the string shown.
558 =item Callback called exit
560 (F) A subroutine invoked from an external package via call_sv()
561 exited by calling exit.
563 =item %s() called too early to check prototype
565 (W prototype) You've called a function that has a prototype before the
566 parser saw a definition or declaration for it, and Perl could not check
567 that the call conforms to the prototype. You need to either add an
568 early prototype declaration for the subroutine in question, or move the
569 subroutine definition ahead of the call to get proper prototype
570 checking. Alternatively, if you are certain that you're calling the
571 function correctly, you may put an ampersand before the name to avoid
572 the warning. See L<perlsub>.
574 =item Calling POSIX::%s() is deprecated
576 (D deprecated) You called a function whose use is deprecated. See
577 the function's name in L<POSIX> for details.
581 (F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
583 =item Cannot compress %f in pack
585 (F) You tried compressing an infinity or not-a-number as an unsigned
586 integer with BER, which makes no sense.
588 =item Cannot compress integer in pack
590 (F) An argument to pack("w",...) was too large to compress.
591 The BER compressed integer format can only be used with positive
592 integers, and you attempted to compress a very large number (> 1e308).
593 See L<perlfunc/pack>.
595 =item Cannot compress negative numbers in pack
597 (F) An argument to pack("w",...) was negative. The BER compressed integer
598 format can only be used with positive integers. See L<perlfunc/pack>.
600 =item Cannot convert a reference to %s to typeglob
602 (F) You manipulated Perl's symbol table directly, stored a reference
603 in it, then tried to access that symbol via conventional Perl syntax.
604 The access triggers Perl to autovivify that typeglob, but it there is
605 no legal conversion from that type of reference to a typeglob.
607 =item Cannot copy to %s
609 (P) Perl detected an attempt to copy a value to an internal type that cannot
610 be directly assigned to.
612 =item Cannot find encoding "%s"
614 (S io) You tried to apply an encoding that did not exist to a filehandle,
615 either with open() or binmode().
617 =item Cannot pack %f with '%c'
619 (F) You tried converting an infinity or not-a-number to an integer,
620 which makes no sense.
622 =item Cannot printf %f with '%c'
624 (F) You tried printing an infinity or not-a-number as a character (%c),
625 which makes no sense. Maybe you meant '%s', or just stringifying it?
627 =item Cannot set tied @DB::args
629 (F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
630 is not supported. (Before this error was added, it used to crash.)
632 =item Cannot tie unreifiable array
634 (P) You somehow managed to call C<tie> on an array that does not
635 keep a reference count on its arguments and cannot be made to
636 do so. Such arrays are not even supposed to be accessible to
637 Perl code, but are only used internally.
639 =item Can only compress unsigned integers in pack
641 (F) An argument to pack("w",...) was not an integer. The BER compressed
642 integer format can only be used with positive integers, and you attempted
643 to compress something else. See L<perlfunc/pack>.
645 =item Can't bless non-reference value
647 (F) Only hard references may be blessed. This is how Perl "enforces"
648 encapsulation of objects. See L<perlobj>.
650 =item Can't "break" in a loop topicalizer
652 (F) You called C<break>, but you're in a C<foreach> block rather than
653 a C<given> block. You probably meant to use C<next> or C<last>.
655 =item Can't "break" outside a given block
657 (F) You called C<break>, but you're not inside a C<given> block.
659 =item Can't call method "%s" on an undefined value
661 (F) You used the syntax of a method call, but the slot filled by the
662 object reference or package name contains an undefined value. Something
663 like this will reproduce the error:
666 process $BADREF 1,2,3;
667 $BADREF->process(1,2,3);
669 =item Can't call method "%s" on unblessed reference
671 (F) A method call must know in what package it's supposed to run. It
672 ordinarily finds this out from the object reference you supply, but you
673 didn't supply an object reference in this case. A reference isn't an
674 object reference until it has been blessed. See L<perlobj>.
676 =item Can't call method "%s" without a package or object reference
678 (F) You used the syntax of a method call, but the slot filled by the
679 object reference or package name contains an expression that returns a
680 defined value which is neither an object reference nor a package name.
681 Something like this will reproduce the error:
684 process $BADREF 1,2,3;
685 $BADREF->process(1,2,3);
687 =item Can't call mro_isa_changed_in() on anonymous symbol table
689 (P) Perl got confused as to whether a hash was a plain hash or a
690 symbol table hash when trying to update @ISA caches.
692 =item Can't call mro_method_changed_in() on anonymous symbol table
694 (F) An XS module tried to call C<mro_method_changed_in> on a hash that was
695 not attached to the symbol table.
697 =item Can't chdir to %s
699 (F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
700 that you can chdir to, possibly because it doesn't exist.
702 =item Can't check filesystem of script "%s" for nosuid
704 (P) For some reason you can't check the filesystem of the script for
707 =item Can't coerce %s to %s in %s
709 (F) Certain types of SVs, in particular real symbol table entries
710 (typeglobs), can't be forced to stop being what they are. So you can't
720 but then $foo no longer contains a glob.
722 =item Can't "continue" outside a when block
724 (F) You called C<continue>, but you're not inside a C<when>
727 =item Can't create pipe mailbox
729 (P) An error peculiar to VMS. The process is suffering from exhausted
730 quotas or other plumbing problems.
732 =item Can't declare %s in "%s"
734 (F) Only scalar, array, and hash variables may be declared as "my", "our" or
735 "state" variables. They must have ordinary identifiers as names.
737 =item Can't "default" outside a topicalizer
739 (F) You have used a C<default> block that is neither inside a
740 C<foreach> loop nor a C<given> block. (Note that this error is
741 issued on exit from the C<default> block, so you won't get the
742 error if you use an explicit C<continue>.)
744 =item Can't do %s("%s") on non-UTF-8 locale; resolved to "%s".
746 (W locale) You are 1) running under "C<use locale>"; 2) the current
747 locale is not a UTF-8 one; 3) you tried to do the designated case-change
748 operation on the specified Unicode character; and 4) the result of this
749 operation would mix Unicode and locale rules, which likely conflict.
750 Mixing of different rule types is forbidden, so the operation was not
751 done; instead the result is the indicated value, which is the best
752 available that uses entirely Unicode rules. That turns out to almost
753 always be the original character, unchanged.
755 It is generally a bad idea to mix non-UTF-8 locales and Unicode, and
756 this issue is one of the reasons why. This warning is raised when
757 Unicode rules would normally cause the result of this operation to
758 contain a character that is in the range specified by the locale,
759 0..255, and hence is subject to the locale's rules, not Unicode's.
761 If you are using locale purely for its characteristics related to things
762 like its numeric and time formatting (and not C<LC_CTYPE>), consider
763 using a restricted form of the locale pragma (see L<perllocale/The "use
764 locale" pragma>) like "S<C<use locale ':not_characters'>>".
766 Note that failed case-changing operations done as a result of
767 case-insensitive C</i> regular expression matching will show up in this
768 warning as having the C<fc> operation (as that is what the regular
769 expression engine calls behind the scenes.)
771 =item Can't do inplace edit: %s is not a regular file
773 (S inplace) You tried to use the B<-i> switch on a special file, such as
774 a file in /dev, a FIFO or an uneditable directory. The file was ignored.
776 =item Can't do inplace edit on %s: %s
778 (S inplace) The creation of the new file failed for the indicated
781 =item Can't do inplace edit without backup
783 (F) You're on a system such as MS-DOS that gets confused if you try
784 reading from a deleted (but still opened) file. You have to say
785 C<-i.bak>, or some such.
787 =item Can't do inplace edit: %s would not be unique
789 (S inplace) Your filesystem does not support filenames longer than 14
790 characters and Perl was unable to create a unique filename during
791 inplace editing with the B<-i> switch. The file was ignored.
793 =item Can't do waitpid with flags
795 (F) This machine doesn't have either waitpid() or wait4(), so only
796 waitpid() without flags is emulated.
798 =item Can't emulate -%s on #! line
800 (F) The #! line specifies a switch that doesn't make sense at this
801 point. For example, it'd be kind of silly to put a B<-x> on the #!
804 =item Can't %s %s-endian %ss on this platform
806 (F) Your platform's byte-order is neither big-endian nor little-endian,
807 or it has a very strange pointer size. Packing and unpacking big- or
808 little-endian floating point values and pointers may not be possible.
809 See L<perlfunc/pack>.
811 =item Can't exec "%s": %s
813 (W exec) A system(), exec(), or piped open call could not execute the
814 named program for the indicated reason. Typical reasons include: the
815 permissions were wrong on the file, the file wasn't found in
816 C<$ENV{PATH}>, the executable in question was compiled for another
817 architecture, or the #! line in a script points to an interpreter that
818 can't be run for similar reasons. (Or maybe your system doesn't support
823 (F) Perl was trying to execute the indicated program for you because
824 that's what the #! line said. If that's not what you wanted, you may
825 need to mention "perl" on the #! line somewhere.
827 =item Can't execute %s
829 (F) You used the B<-S> switch, but the copies of the script to execute
830 found in the PATH did not have correct permissions.
832 =item Can't find an opnumber for "%s"
834 (F) A string of a form C<CORE::word> was given to prototype(), but there
835 is no builtin with the name C<word>.
837 =item Can't find %s character property "%s"
839 (F) You used C<\p{}> or C<\P{}> but the character property by that name
840 could not be found. Maybe you misspelled the name of the property?
841 See L<perluniprops/Properties accessible through \p{} and \P{}>
842 for a complete list of available official properties.
844 =item Can't find label %s
846 (F) You said to goto a label that isn't mentioned anywhere that it's
847 possible for us to go to. See L<perlfunc/goto>.
849 =item Can't find %s on PATH
851 (F) You used the B<-S> switch, but the script to execute could not be
854 =item Can't find %s on PATH, '.' not in PATH
856 (F) You used the B<-S> switch, but the script to execute could not be
857 found in the PATH, or at least not with the correct permissions. The
858 script exists in the current directory, but PATH prohibits running it.
860 =item Can't find string terminator %s anywhere before EOF
862 (F) Perl strings can stretch over multiple lines. This message means
863 that the closing delimiter was omitted. Because bracketed quotes count
864 nesting levels, the following is missing its final parenthesis:
866 print q(The character '(' starts a side comment.);
868 If you're getting this error from a here-document, you may have
869 included unseen whitespace before or after your closing tag or there
870 may not be a linebreak after it. A good programmer's editor will have
871 a way to help you find these characters (or lack of characters). See
872 L<perlop> for the full details on here-documents.
874 =item Can't find Unicode property definition "%s"
876 (F) You may have tried to use C<\p> which means a Unicode
877 property (for example C<\p{Lu}> matches all uppercase
878 letters). If you did mean to use a Unicode property, see
879 L<perluniprops/Properties accessible through \p{} and \P{}>
880 for a complete list of available properties. If you didn't
881 mean to use a Unicode property, escape the C<\p>, either by
882 C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
887 (F) A fatal error occurred while trying to fork while opening a
890 =item Can't fork, trying again in 5 seconds
892 (W pipe) A fork in a piped open failed with EAGAIN and will be retried
895 =item Can't get filespec - stale stat buffer?
897 (S) A warning peculiar to VMS. This arises because of the difference
898 between access checks under VMS and under the Unix model Perl assumes.
899 Under VMS, access checks are done by filename, rather than by bits in
900 the stat buffer, so that ACLs and other protections can be taken into
901 account. Unfortunately, Perl assumes that the stat buffer contains all
902 the necessary information, and passes it, instead of the filespec, to
903 the access-checking routine. It will try to retrieve the filespec using
904 the device name and FID present in the stat buffer, but this works only
905 if you haven't made a subsequent call to the CRTL stat() routine,
906 because the device name is overwritten with each call. If this warning
907 appears, the name lookup failed, and the access-checking routine gave up
908 and returned FALSE, just to be conservative. (Note: The access-checking
909 routine knows about the Perl C<stat> operator and file tests, so you
910 shouldn't ever see this warning in response to a Perl command; it arises
911 only if some internal code takes stat buffers lightly.)
913 =item Can't get pipe mailbox device name
915 (P) An error peculiar to VMS. After creating a mailbox to act as a
916 pipe, Perl can't retrieve its name for later use.
918 =item Can't get SYSGEN parameter value for MAXBUF
920 (P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
921 mailbox buffers to be, and didn't get an answer.
923 =item Can't "goto" into the middle of a foreach loop
925 (F) A "goto" statement was executed to jump into the middle of a foreach
926 loop. You can't get there from here. See L<perlfunc/goto>.
928 =item Can't "goto" out of a pseudo block
930 (F) A "goto" statement was executed to jump out of what might look like
931 a block, except that it isn't a proper block. This usually occurs if
932 you tried to jump out of a sort() block or subroutine, which is a no-no.
933 See L<perlfunc/goto>.
935 =item Can't goto subroutine from an eval-%s
937 (F) The "goto subroutine" call can't be used to jump out of an eval
940 =item Can't goto subroutine from a sort sub (or similar callback)
942 (F) The "goto subroutine" call can't be used to jump out of the
943 comparison sub for a sort(), or from a similar callback (such
944 as the reduce() function in List::Util).
946 =item Can't goto subroutine outside a subroutine
948 (F) The deeply magical "goto subroutine" call can only replace one
949 subroutine call for another. It can't manufacture one out of whole
950 cloth. In general you should be calling it out of only an AUTOLOAD
951 routine anyway. See L<perlfunc/goto>.
953 =item Can't ignore signal CHLD, forcing to default
955 (W signal) Perl has detected that it is being run with the SIGCHLD
956 signal (sometimes known as SIGCLD) disabled. Since disabling this
957 signal will interfere with proper determination of exit status of child
958 processes, Perl has reset the signal to its default value. This
959 situation typically indicates that the parent program under which Perl
960 may be running (e.g. cron) is being very careless.
962 =item Can't kill a non-numeric process ID
964 (F) Process identifiers must be (signed) integers. It is a fatal error to
965 attempt to kill() an undefined, empty-string or otherwise non-numeric
968 =item Can't "last" outside a loop block
970 (F) A "last" statement was executed to break out of the current block,
971 except that there's this itty bitty problem called there isn't a current
972 block. Note that an "if" or "else" block doesn't count as a "loopish"
973 block, as doesn't a block given to sort(), map() or grep(). You can
974 usually double the curlies to get the same effect though, because the
975 inner curlies will be considered a block that loops once. See
978 =item Can't linearize anonymous symbol table
980 (F) Perl tried to calculate the method resolution order (MRO) of a
981 package, but failed because the package stash has no name.
983 =item Can't load '%s' for module %s
985 (F) The module you tried to load failed to load a dynamic extension.
986 This may either mean that you upgraded your version of perl to one
987 that is incompatible with your old dynamic extensions (which is known
988 to happen between major versions of perl), or (more likely) that your
989 dynamic extension was built against an older version of the library
990 that is installed on your system. You may need to rebuild your old
993 =item Can't localize lexical variable %s
995 (F) You used local on a variable name that was previously declared as a
996 lexical variable using "my" or "state". This is not allowed. If you
997 want to localize a package variable of the same name, qualify it with
1000 =item Can't localize through a reference
1002 (F) You said something like C<local $$ref>, which Perl can't currently
1003 handle, because when it goes to restore the old value of whatever $ref
1004 pointed to after the scope of the local() is finished, it can't be sure
1005 that $ref will still be a reference.
1007 =item Can't locate %s
1009 (F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
1010 Perl looks for the file in all the locations mentioned in @INC, unless
1011 the file name included the full path to the file. Perhaps you need
1012 to set the PERL5LIB or PERL5OPT environment variable to say where the
1013 extra library is, or maybe the script needs to add the library name
1014 to @INC. Or maybe you just misspelled the name of the file. See
1015 L<perlfunc/require> and L<lib>.
1017 =item Can't locate auto/%s.al in @INC
1019 (F) A function (or method) was called in a package which allows
1020 autoload, but there is no function to autoload. Most probable causes
1021 are a misprint in a function/method name or a failure to C<AutoSplit>
1022 the file, say, by doing C<make install>.
1024 =item Can't locate loadable object for module %s in @INC
1026 (F) The module you loaded is trying to load an external library, like
1027 for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
1028 unable to locate this library. See L<DynaLoader>.
1030 =item Can't locate object method "%s" via package "%s"
1032 (F) You called a method correctly, and it correctly indicated a package
1033 functioning as a class, but that package doesn't define that particular
1034 method, nor does any of its base classes. See L<perlobj>.
1036 =item Can't locate object method "%s" via package "%s" (perhaps you forgot
1039 (F) You called a method on a class that did not exist, and the method
1040 could not be found in UNIVERSAL. This often means that a method
1041 requires a package that has not been loaded.
1043 =item Can't locate package %s for @%s::ISA
1045 (W syntax) The @ISA array contained the name of another package that
1046 doesn't seem to exist.
1048 =item Can't locate PerlIO%s
1050 (F) You tried to use in open() a PerlIO layer that does not exist,
1051 e.g. open(FH, ">:nosuchlayer", "somefile").
1053 =item Can't make list assignment to %ENV on this system
1055 (F) List assignment to %ENV is not supported on some systems, notably
1058 =item Can't make loaded symbols global on this platform while loading %s
1060 (S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
1061 that symbols from the stated file are made available globally within the
1062 process, but that functionality is not available on this platform. Whilst
1063 the module likely will still work, this may prevent the perl interpreter
1064 from loading other XS-based extensions which need to link directly to
1065 functions defined in the C or XS code in the stated file.
1067 =item Can't modify %s in %s
1069 (F) You aren't allowed to assign to the item indicated, or otherwise try
1070 to change it, such as with an auto-increment.
1072 =item Can't modify nonexistent substring
1074 (P) The internal routine that does assignment to a substr() was handed
1077 =item Can't modify non-lvalue subroutine call
1079 (F) Subroutines meant to be used in lvalue context should be declared as
1080 such. See L<perlsub/"Lvalue subroutines">.
1082 =item Can't modify reference to %s in %s assignment
1084 (F) Only a limited number of constructs can be used as the argument to a
1085 reference constructor on the left-hand side of an assignment, and what
1086 you used was not one of them. See L<perlref/Assigning to References>.
1088 =item Can't modify reference to localized parenthesized array in list
1091 (F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1092 it is not clear exactly what it should do. If you meant to make @array
1093 refer to some other array, use C<\@array = \@other_array>. If you want to
1094 make the elements of @array aliases of the scalars referenced on the
1095 right-hand side, use C<\(@array) = @scalar_refs>.
1097 =item Can't modify reference to parenthesized hash in list assignment
1099 (F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1100 refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1101 make the elements of %hash into aliases of the scalars referenced on the
1102 right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1104 =item Can't msgrcv to read-only var
1106 (F) The target of a msgrcv must be modifiable to be used as a receive
1109 =item Can't "next" outside a loop block
1111 (F) A "next" statement was executed to reiterate the current block, but
1112 there isn't a current block. Note that an "if" or "else" block doesn't
1113 count as a "loopish" block, as doesn't a block given to sort(), map() or
1114 grep(). You can usually double the curlies to get the same effect
1115 though, because the inner curlies will be considered a block that loops
1116 once. See L<perlfunc/next>.
1118 =item Can't open %s: %s
1120 (S inplace) The implicit opening of a file through use of the C<< <> >>
1121 filehandle, either implicitly under the C<-n> or C<-p> command-line
1122 switches, or explicitly, failed for the indicated reason. Usually
1123 this is because you don't have read permission for a file which
1124 you named on the command line.
1126 (F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1127 your operating system's equivalent) could not be opened.
1129 =item Can't open a reference
1131 (W io) You tried to open a scalar reference for reading or writing,
1132 using the 3-arg open() syntax:
1136 but your version of perl is compiled without perlio, and this form of
1137 open is not supported.
1139 =item Can't open bidirectional pipe
1141 (W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1142 You can try any of several modules in the Perl library to do this, such
1143 as IPC::Open2. Alternately, direct the pipe's output to a file using
1144 ">", and then read it in under a different file handle.
1146 =item Can't open error file %s as stderr
1148 (F) An error peculiar to VMS. Perl does its own command line
1149 redirection, and couldn't open the file specified after '2>' or '2>>' on
1150 the command line for writing.
1152 =item Can't open input file %s as stdin
1154 (F) An error peculiar to VMS. Perl does its own command line
1155 redirection, and couldn't open the file specified after '<' on the
1156 command line for reading.
1158 =item Can't open output file %s as stdout
1160 (F) An error peculiar to VMS. Perl does its own command line
1161 redirection, and couldn't open the file specified after '>' or '>>' on
1162 the command line for writing.
1164 =item Can't open output pipe (name: %s)
1166 (P) An error peculiar to VMS. Perl does its own command line
1167 redirection, and couldn't open the pipe into which to send data destined
1170 =item Can't open perl script "%s": %s
1172 (F) The script you specified can't be opened for the indicated reason.
1174 If you're debugging a script that uses #!, and normally relies on the
1175 shell's $PATH search, the -S option causes perl to do that search, so
1176 you don't have to type the path or C<`which $scriptname`>.
1178 =item Can't read CRTL environ
1180 (S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1181 from the CRTL's internal environment array and discovered the array was
1182 missing. You need to figure out where your CRTL misplaced its environ
1183 or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1186 =item Can't "redo" outside a loop block
1188 (F) A "redo" statement was executed to restart the current block, but
1189 there isn't a current block. Note that an "if" or "else" block doesn't
1190 count as a "loopish" block, as doesn't a block given to sort(), map()
1191 or grep(). You can usually double the curlies to get the same effect
1192 though, because the inner curlies will be considered a block that
1193 loops once. See L<perlfunc/redo>.
1195 =item Can't remove %s: %s, skipping file
1197 (S inplace) You requested an inplace edit without creating a backup
1198 file. Perl was unable to remove the original file to replace it with
1199 the modified file. The file was left unmodified.
1201 =item Can't rename %s to %s: %s, skipping file
1203 (S inplace) The rename done by the B<-i> switch failed for some reason,
1204 probably because you don't have write permission to the directory.
1206 =item Can't reopen input pipe (name: %s) in binary mode
1208 (P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1209 to reopen it to accept binary data. Alas, it failed.
1211 =item Can't represent character for Ox%X on this platform
1213 (F) There is a hard limit to how big a character code point can be due
1214 to the fundamental properties of UTF-8, especially on EBCDIC
1215 platforms. The given code point exceeds that. The only work-around is
1216 to not use such a large code point.
1218 =item Can't reset %ENV on this system
1220 (F) You called C<reset('E')> or similar, which tried to reset
1221 all variables in the current package beginning with "E". In
1222 the main package, that includes %ENV. Resetting %ENV is not
1223 supported on some systems, notably VMS.
1225 =item Can't resolve method "%s" overloading "%s" in package "%s"
1227 (F)(P) Error resolving overloading specified by a method name (as
1228 opposed to a subroutine reference): no such method callable via the
1229 package. If the method name is C<???>, this is an internal error.
1231 =item Can't return %s from lvalue subroutine
1233 (F) Perl detected an attempt to return illegal lvalues (such as
1234 temporary or readonly values) from a subroutine used as an lvalue. This
1237 =item Can't return outside a subroutine
1239 (F) The return statement was executed in mainline code, that is, where
1240 there was no subroutine call to return out of. See L<perlsub>.
1242 =item Can't return %s to lvalue scalar context
1244 (F) You tried to return a complete array or hash from an lvalue
1245 subroutine, but you called the subroutine in a way that made Perl
1246 think you meant to return only one value. You probably meant to
1247 write parentheses around the call to the subroutine, which tell
1248 Perl that the call should be in list context.
1250 =item Can't stat script "%s"
1252 (P) For some reason you can't fstat() the script even though you have it
1253 open already. Bizarre.
1255 =item Can't take log of %g
1257 (F) For ordinary real numbers, you can't take the logarithm of a
1258 negative number or zero. There's a Math::Complex package that comes
1259 standard with Perl, though, if you really want to do that for the
1262 =item Can't take sqrt of %g
1264 (F) For ordinary real numbers, you can't take the square root of a
1265 negative number. There's a Math::Complex package that comes standard
1266 with Perl, though, if you really want to do that.
1268 =item Can't undef active subroutine
1270 (F) You can't undefine a routine that's currently running. You can,
1271 however, redefine it while it's running, and you can even undef the
1272 redefined subroutine while the old routine is running. Go figure.
1274 =item Can't upgrade %s (%d) to %d
1276 (P) The internal sv_upgrade routine adds "members" to an SV, making it
1277 into a more specialized kind of SV. The top several SV types are so
1278 specialized, however, that they cannot be interconverted. This message
1279 indicates that such a conversion was attempted.
1281 =item Can't use '%c' after -mname
1283 (F) You tried to call perl with the B<-m> switch, but you put something
1284 other than "=" after the module name.
1286 =item Can't use a hash as a reference
1288 (F) You tried to use a hash as a reference, as in
1289 C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1290 <= 5.22.0 used to allow this syntax, but shouldn't
1291 have. This was deprecated in perl 5.6.1.
1293 =item Can't use an array as a reference
1295 (F) You tried to use an array as a reference, as in
1296 C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1297 used to allow this syntax, but shouldn't have. This
1298 was deprecated in perl 5.6.1.
1300 =item Can't use anonymous symbol table for method lookup
1302 (F) The internal routine that does method lookup was handed a symbol
1303 table that doesn't have a name. Symbol tables can become anonymous
1304 for example by undefining stashes: C<undef %Some::Package::>.
1306 =item Can't use an undefined value as %s reference
1308 (F) A value used as either a hard reference or a symbolic reference must
1309 be a defined value. This helps to delurk some insidious errors.
1311 =item Can't use bareword ("%s") as %s ref while "strict refs" in use
1313 (F) Only hard references are allowed by "strict refs". Symbolic
1314 references are disallowed. See L<perlref>.
1316 =item Can't use %! because Errno.pm is not available
1318 (F) The first time the C<%!> hash is used, perl automatically loads the
1319 Errno.pm module. The Errno module is expected to tie the %! hash to
1320 provide symbolic names for C<$!> errno values.
1322 =item Can't use both '<' and '>' after type '%c' in %s
1324 (F) A type cannot be forced to have both big-endian and little-endian
1325 byte-order at the same time, so this combination of modifiers is not
1326 allowed. See L<perlfunc/pack>.
1328 =item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1330 (F) defined() is not useful on arrays because it
1331 checks for an undefined I<scalar> value. If you want to see if the
1332 array is empty, just use C<if (@array) { # not empty }> for example.
1334 =item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1336 (F) C<defined()> is not usually right on hashes.
1338 Although C<defined %hash> is false on a plain not-yet-used hash, it
1339 becomes true in several non-obvious circumstances, including iterators,
1340 weak references, stash names, even remaining true after C<undef %hash>.
1341 These things make C<defined %hash> fairly useless in practice, so it now
1342 generates a fatal error.
1344 If a check for non-empty is what you wanted then just put it in boolean
1345 context (see L<perldata/Scalar values>):
1351 If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1352 variable exists then that's never really been reliable, and isn't
1353 a good way to enquire about the features of a package, or whether
1356 =item Can't use %s for loop variable
1358 (F) Only a simple scalar variable may be used as a loop variable on a
1361 =item Can't use global %s in "%s"
1363 (F) You tried to declare a magical variable as a lexical variable. This
1364 is not allowed, because the magic can be tied to only one location
1365 (namely the global variable) and it would be incredibly confusing to
1366 have variables in your program that looked like magical variables but
1369 =item Can't use '%c' in a group with different byte-order in %s
1371 (F) You attempted to force a different byte-order on a type
1372 that is already inside a group with a byte-order modifier.
1373 For example you cannot force little-endianness on a type that
1374 is inside a big-endian group.
1376 =item Can't use "my %s" in sort comparison
1378 (F) The global variables $a and $b are reserved for sort comparisons.
1379 You mentioned $a or $b in the same line as the <=> or cmp operator,
1380 and the variable had earlier been declared as a lexical variable.
1381 Either qualify the sort variable with the package name, or rename the
1384 =item Can't use %s ref as %s ref
1386 (F) You've mixed up your reference types. You have to dereference a
1387 reference of the type needed. You can use the ref() function to
1388 test the type of the reference, if need be.
1390 =item Can't use string ("%s") as %s ref while "strict refs" in use
1392 =item Can't use string ("%s"...) as %s ref while "strict refs" in use
1394 (F) You've told Perl to dereference a string, something which
1395 C<use strict> blocks to prevent it happening accidentally. See
1396 L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1397 in a double-quoted string immediately before interpolating a variable,
1398 for example in C<"user @$twitter_id">, which says to treat the contents
1399 of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1400 symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
1402 =item Can't use subscript on %s
1404 (F) The compiler tried to interpret a bracketed expression as a
1405 subscript. But to the left of the brackets was an expression that
1406 didn't look like a hash or array reference, or anything else subscriptable.
1408 =item Can't use \%c to mean $%c in expression
1410 (W syntax) In an ordinary expression, backslash is a unary operator that
1411 creates a reference to its argument. The use of backslash to indicate a
1412 backreference to a matched substring is valid only as part of a regular
1413 expression pattern. Trying to do this in ordinary Perl code produces a
1414 value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1417 =item Can't weaken a nonreference
1419 (F) You attempted to weaken something that was not a reference. Only
1420 references can be weakened.
1422 =item Can't "when" outside a topicalizer
1424 (F) You have used a when() block that is neither inside a C<foreach>
1425 loop nor a C<given> block. (Note that this error is issued on exit
1426 from the C<when> block, so you won't get the error if the match fails,
1427 or if you use an explicit C<continue>.)
1429 =item Can't x= to read-only value
1431 (F) You tried to repeat a constant value (often the undefined value)
1432 with an assignment operator, which implies modifying the value itself.
1433 Perhaps you need to copy the value to a temporary, and repeat that.
1435 =item Character following "\c" must be printable ASCII
1437 (F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
1439 Note that ASCII characters that don't map to control characters are
1440 discouraged, and will generate the warning (when enabled)
1441 L</""\c%c" is more clearly written simply as "%s"">.
1443 =item Character in 'C' format wrapped in pack
1449 where $x is either less than 0 or more than 255; the C<"C"> format is
1450 only for encoding native operating system characters (ASCII, EBCDIC,
1451 and so on) and not for Unicode characters, so Perl behaved as if you meant
1455 If you actually want to pack Unicode codepoints, use the C<"U"> format
1458 =item Character in 'c' format wrapped in pack
1464 where $x is either less than -128 or more than 127; the C<"c"> format
1465 is only for encoding native operating system characters (ASCII, EBCDIC,
1466 and so on) and not for Unicode characters, so Perl behaved as if you meant
1468 pack("c", $x & 255);
1470 If you actually want to pack Unicode codepoints, use the C<"U"> format
1473 =item Character in '%c' format wrapped in unpack
1475 (W unpack) You tried something like
1477 unpack("H", "\x{2a1}")
1479 where the format expects to process a byte (a character with a value
1480 below 256), but a higher value was provided instead. Perl uses the
1481 value modulus 256 instead, as if you had provided:
1483 unpack("H", "\x{a1}")
1485 =item Character in 'W' format wrapped in pack
1491 where $x is either less than 0 or more than 255. However, C<U0>-mode
1492 expects all values to fall in the interval [0, 255], so Perl behaved
1495 pack("U0W", $x & 255)
1497 =item Character(s) in '%c' format wrapped in pack
1499 (W pack) You tried something like
1501 pack("u", "\x{1f3}b")
1503 where the format expects to process a sequence of bytes (character with a
1504 value below 256), but some of the characters had a higher value. Perl
1505 uses the character values modulus 256 instead, as if you had provided:
1507 pack("u", "\x{f3}b")
1509 =item Character(s) in '%c' format wrapped in unpack
1511 (W unpack) You tried something like
1513 unpack("s", "\x{1f3}b")
1515 where the format expects to process a sequence of bytes (character with a
1516 value below 256), but some of the characters had a higher value. Perl
1517 uses the character values modulus 256 instead, as if you had provided:
1519 unpack("s", "\x{f3}b")
1521 =item charnames alias definitions may not contain a sequence of multiple spaces
1523 (F) You defined a character name which had multiple space characters
1524 in a row. Change them to single spaces. Usually these names are
1525 defined in the C<:alias> import argument to C<use charnames>, but they
1526 could be defined by a translator installed into C<$^H{charnames}>. See
1527 L<charnames/CUSTOM ALIASES>.
1529 =item charnames alias definitions may not contain trailing white-space
1531 (F) You defined a character name which ended in a space
1532 character. Remove the trailing space(s). Usually these names are
1533 defined in the C<:alias> import argument to C<use charnames>, but they
1534 could be defined by a translator installed into C<$^H{charnames}>.
1535 See L<charnames/CUSTOM ALIASES>.
1537 =item \C is deprecated in regex; marked by <-- HERE in m/%s/
1539 (D deprecated, regexp) The \C character class is deprecated, and will
1540 become a compile-time error in a future release of perl (tentatively
1541 v5.24). This construct allows you to match a single byte of what makes
1542 up a multi-byte single UTF8 character, and breaks encapsulation. It is
1543 currently also very buggy. If you really need to process the individual
1544 bytes, you probably want to convert your string to one where each
1545 underlying byte is stored as a character, with utf8::encode().
1547 =item "\c%c" is more clearly written simply as "%s"
1549 (W syntax) The C<\cI<X>> construct is intended to be a way to specify
1550 non-printable characters. You used it for a printable one, which
1551 is better written as simply itself, perhaps preceded by a backslash
1552 for non-word characters. Doing it the way you did is not portable
1553 between ASCII and EBCDIC platforms.
1555 =item Cloning substitution context is unimplemented
1557 (F) Creating a new thread inside the C<s///> operator is not supported.
1559 =item closedir() attempted on invalid dirhandle %s
1561 (W io) The dirhandle you tried to close is either closed or not really
1562 a dirhandle. Check your control flow.
1564 =item close() on unopened filehandle %s
1566 (W unopened) You tried to close a filehandle that was never opened.
1568 =item Closure prototype called
1570 (F) If a closure has attributes, the subroutine passed to an attribute
1571 handler is the prototype that is cloned when a new closure is created.
1572 This subroutine cannot be called.
1574 =item Code missing after '/'
1576 (F) You had a (sub-)template that ends with a '/'. There must be
1577 another template code following the slash. See L<perlfunc/pack>.
1579 =item Code point 0x%X is not Unicode, may not be portable
1581 (S non_unicode) You had a code point above the Unicode maximum
1584 Perl allows strings to contain a superset of Unicode code points, up
1585 to the limit of what is storable in an unsigned integer on your system,
1586 but these may not be accepted by other languages/systems. At one time,
1587 it was legal in some standards to have code points up to 0x7FFF_FFFF,
1588 but not higher. Code points above 0xFFFF_FFFF require larger than a
1591 =item %s: Command not found
1593 (A) You've accidentally run your script through B<csh> or another shell
1594 instead of Perl. Check the #! line, or manually feed your script into
1595 Perl yourself. The #! line at the top of your file could look like
1599 =item Compilation failed in require
1601 (F) Perl could not compile a file specified in a C<require> statement.
1602 Perl uses this generic message when none of the errors that it
1603 encountered were severe enough to halt compilation immediately.
1605 =item Complex regular subexpression recursion limit (%d) exceeded
1607 (W regexp) The regular expression engine uses recursion in complex
1608 situations where back-tracking is required. Recursion depth is limited
1609 to 32766, or perhaps less in architectures where the stack cannot grow
1610 arbitrarily. ("Simple" and "medium" situations are handled without
1611 recursion and are not subject to a limit.) Try shortening the string
1612 under examination; looping in Perl code (e.g. with C<while>) rather than
1613 in the regular expression engine; or rewriting the regular expression so
1614 that it is simpler or backtracks less. (See L<perlfaq2> for information
1615 on I<Mastering Regular Expressions>.)
1617 =item connect() on closed socket %s
1619 (W closed) You tried to do a connect on a closed socket. Did you forget
1620 to check the return value of your socket() call? See
1621 L<perlfunc/connect>.
1623 =item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1625 (F) The subroutine registered to handle constant overloading
1626 (see L<overload>) or a custom charnames handler (see
1627 L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1629 =item Constant(%s): $^H{%s} is not defined
1631 (F) The parser found inconsistencies while attempting to define an
1632 overloaded constant. Perhaps you forgot to load the corresponding
1635 =item Constant is not %s reference
1637 (F) A constant value (perhaps declared using the C<use constant> pragma)
1638 is being dereferenced, but it amounts to the wrong type of reference.
1639 The message indicates the type of reference that was expected. This
1640 usually indicates a syntax error in dereferencing the constant value.
1641 See L<perlsub/"Constant Functions"> and L<constant>.
1643 =item Constants from lexical variables potentially modified elsewhere are
1646 (D deprecated) You wrote something like
1649 $sub = sub () { $var };
1651 but $var is referenced elsewhere and could be modified after the C<sub>
1652 expression is evaluated. Either it is explicitly modified elsewhere
1653 (C<$var = 3>) or it is passed to a subroutine or to an operator like
1654 C<printf> or C<map>, which may or may not modify the variable.
1656 Traditionally, Perl has captured the value of the variable at that
1657 point and turned the subroutine into a constant eligible for inlining.
1658 In those cases where the variable can be modified elsewhere, this
1659 breaks the behavior of closures, in which the subroutine captures
1660 the variable itself, rather than its value, so future changes to the
1661 variable are reflected in the subroutine's return value.
1663 This usage is deprecated, because the behavior is likely to change
1664 in a future version of Perl.
1666 If you intended for the subroutine to be eligible for inlining, then
1667 make sure the variable is not referenced elsewhere, possibly by
1671 $sub = sub () { $var2 };
1673 If you do want this subroutine to be a closure that reflects future
1674 changes to the variable that it closes over, add an explicit C<return>:
1677 $sub = sub () { return $var };
1679 =item Constant subroutine %s redefined
1681 (W redefine)(S) You redefined a subroutine which had previously
1682 been eligible for inlining. See L<perlsub/"Constant Functions">
1683 for commentary and workarounds.
1685 =item Constant subroutine %s undefined
1687 (W misc) You undefined a subroutine which had previously been eligible
1688 for inlining. See L<perlsub/"Constant Functions"> for commentary and
1691 =item Constant(%s) unknown
1693 (F) The parser found inconsistencies either while attempting
1694 to define an overloaded constant, or when trying to find the
1695 character name specified in the C<\N{...}> escape. Perhaps you
1696 forgot to load the corresponding L<overload> pragma?.
1698 =item Copy method did not return a reference
1700 (F) The method which overloads "=" is buggy. See
1701 L<overload/Copy Constructor>.
1703 =item &CORE::%s cannot be called directly
1705 (F) You tried to call a subroutine in the C<CORE::> namespace
1706 with C<&foo> syntax or through a reference. Some subroutines
1707 in this package cannot yet be called that way, but must be
1708 called as barewords. Something like this will work:
1710 BEGIN { *shove = \&CORE::push; }
1711 shove @array, 1,2,3; # pushes on to @array
1713 =item CORE::%s is not a keyword
1715 (F) The CORE:: namespace is reserved for Perl keywords.
1717 =item Corrupted regexp opcode %d > %d
1719 (P) This is either an error in Perl, or, if you're using
1720 one, your L<custom regular expression engine|perlreapi>. If not the
1721 latter, report the problem through the L<perlbug> utility.
1723 =item corrupted regexp pointers
1725 (P) The regular expression engine got confused by what the regular
1726 expression compiler gave it.
1728 =item corrupted regexp program
1730 (P) The regular expression engine got passed a regexp program without a
1733 =item Corrupt malloc ptr 0x%x at 0x%x
1735 (P) The malloc package that comes with Perl had an internal failure.
1737 =item Count after length/code in unpack
1739 (F) You had an unpack template indicating a counted-length string, but
1740 you have also specified an explicit size for the string. See
1744 The following are used in lib/diagnostics.t for testing two =items that
1745 share the same description. Changes here need to be propagated to there
1747 =item Deep recursion on anonymous subroutine
1749 =item Deep recursion on subroutine "%s"
1751 (W recursion) This subroutine has called itself (directly or indirectly)
1752 100 times more than it has returned. This probably indicates an
1753 infinite recursion, unless you're writing strange benchmark programs, in
1754 which case it indicates something else.
1756 This threshold can be changed from 100, by recompiling the F<perl> binary,
1757 setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1759 =item (?(DEFINE)....) does not allow branches in regex; marked by
1760 S<<-- HERE> in m/%s/
1762 (F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
1763 most likely cause of this error is that you left out a parenthesis inside
1764 of the C<....> part.
1766 The <-- HERE shows whereabouts in the regular expression the problem was
1769 =item %s defines neither package nor VERSION--version check failed
1771 (F) You said something like "use Module 42" but in the Module file
1772 there are neither package declarations nor a C<$VERSION>.
1774 =item delete argument is index/value array slice, use array slice
1776 (F) You used index/value array slice syntax (C<%array[...]>) as
1777 the argument to C<delete>. You probably meant C<@array[...]> with
1778 an @ symbol instead.
1780 =item delete argument is key/value hash slice, use hash slice
1782 (F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1783 C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1785 =item delete argument is not a HASH or ARRAY element or slice
1787 (F) The argument to C<delete> must be either a hash or array element,
1793 or a hash or array slice, such as:
1795 @foo[$bar, $baz, $xyzzy]
1796 @{$ref->[12]}{"susie", "queue"}
1798 =item Delimiter for here document is too long
1800 (F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1801 long for Perl to handle. You have to be seriously twisted to write code
1802 that triggers this error.
1804 =item Deprecated use of my() in false conditional
1806 (D deprecated) You used a declaration similar to C<my $x if 0>. There
1807 has been a long-standing bug in Perl that causes a lexical variable
1808 not to be cleared at scope exit when its declaration includes a false
1809 conditional. Some people have exploited this bug to achieve a kind of
1810 static variable. Since we intend to fix this bug, we don't want people
1811 relying on this behavior. You can achieve a similar static effect by
1812 declaring the variable in a separate block outside the function, eg
1814 sub f { my $x if 0; return $x++ }
1818 { my $x; sub f { return $x++ } }
1820 Beginning with perl 5.10.0, you can also use C<state> variables to have
1821 lexicals that are initialized only once (see L<feature>):
1823 sub f { state $x; return $x++ }
1825 =item DESTROY created new reference to dead object '%s'
1827 (F) A DESTROY() method created a new reference to the object which is
1828 just being DESTROYed. Perl is confused, and prefers to abort rather
1829 than to create a dangling reference.
1831 =item Did not produce a valid header
1835 =item %s did not return a true value
1837 (F) A required (or used) file must return a true value to indicate that
1838 it compiled correctly and ran its initialization code correctly. It's
1839 traditional to end such a file with a "1;", though any true value would
1840 do. See L<perlfunc/require>.
1842 =item (Did you mean &%s instead?)
1844 (W misc) You probably referred to an imported subroutine &FOO as $FOO or
1847 =item (Did you mean "local" instead of "our"?)
1849 (W misc) Remember that "our" does not localize the declared global
1850 variable. You have declared it again in the same lexical scope, which
1853 =item (Did you mean $ or @ instead of %?)
1855 (W) You probably said %hash{$key} when you meant $hash{$key} or
1856 @hash{@keys}. On the other hand, maybe you just meant %hash and got
1861 (F) You passed die() an empty string (the equivalent of C<die "">) or
1862 you called it with no args and C<$@> was empty.
1864 =item Document contains no data
1868 =item %s does not define %s::VERSION--version check failed
1870 (F) You said something like "use Module 42" but the Module did not
1871 define a C<$VERSION>.
1873 =item '/' does not take a repeat count
1875 (F) You cannot put a repeat count of any kind right after the '/' code.
1876 See L<perlfunc/pack>.
1878 =item Don't know how to get file name
1880 (P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1881 somehow called on another platform. This should not happen.
1883 =item Don't know how to handle magic of type \%o
1885 (P) The internal handling of magical variables has been cursed.
1887 =item do_study: out of memory
1889 (P) This should have been caught by safemalloc() instead.
1891 =item (Do you need to predeclare %s?)
1893 (S syntax) This is an educated guess made in conjunction with the message
1894 "%s found where operator expected". It often means a subroutine or module
1895 name is being referenced that hasn't been declared yet. This may be
1896 because of ordering problems in your file, or because of a missing
1897 "sub", "package", "require", or "use" statement. If you're referencing
1898 something that isn't defined yet, you don't actually have to define the
1899 subroutine or package before the current location. You can use an empty
1900 "sub foo;" or "package FOO;" to enter a "forward" declaration.
1902 =item dump() better written as CORE::dump()
1904 (W misc) You used the obsolescent C<dump()> built-in function, without fully
1905 qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1907 =item dump is not supported
1909 (F) Your machine doesn't support dump/undump.
1911 =item Duplicate free() ignored
1913 (S malloc) An internal routine called free() on something that had
1916 =item Duplicate modifier '%c' after '%c' in %s
1918 (W unpack) You have applied the same modifier more than once after a
1919 type in a pack template. See L<perlfunc/pack>.
1921 =item each on reference is experimental
1923 (S experimental::autoderef) C<each> with a scalar argument is experimental
1924 and may change or be removed in a future Perl version. If you want to
1925 take the risk of using this feature, simply disable this warning:
1927 no warnings "experimental::autoderef";
1929 =item elseif should be elsif
1931 (S syntax) There is no keyword "elseif" in Perl because Larry thinks
1932 it's ugly. Your code will be interpreted as an attempt to call a method
1933 named "elseif" for the class returned by the following block. This is
1934 unlikely to be what you want.
1936 =item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
1938 (F) C<\p> and C<\P> are used to introduce a named Unicode property, as
1939 described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
1940 a regular expression without specifying the property name.
1942 =item entering effective %s failed
1944 (F) While under the C<use filetest> pragma, switching the real and
1945 effective uids or gids failed.
1947 =item %ENV is aliased to %s
1949 (F) You're running under taint mode, and the C<%ENV> variable has been
1950 aliased to another hash, so it doesn't reflect anymore the state of the
1951 program's environment. This is potentially insecure.
1953 =item Error converting file specification %s
1955 (F) An error peculiar to VMS. Because Perl may have to deal with file
1956 specifications in either VMS or Unix syntax, it converts them to a
1957 single form when it must operate on them directly. Either you've passed
1958 an invalid file specification to Perl, or you've found a case the
1959 conversion routines don't handle. Drat.
1961 =item Eval-group in insecure regular expression
1963 (F) Perl detected tainted data when trying to compile a regular
1964 expression that contains the C<(?{ ... })> zero-width assertion, which
1965 is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
1967 =item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
1969 (F) Perl tried to compile a regular expression containing the
1970 C<(?{ ... })> zero-width assertion at run time, as it would when the
1971 pattern contains interpolated values. Since that is a security risk,
1972 it is not allowed. If you insist, you may still do this by using the
1973 C<re 'eval'> pragma or by explicitly building the pattern from an
1974 interpolated string at run time and using that in an eval(). See
1975 L<perlre/(?{ code })>.
1977 =item Eval-group not allowed, use re 'eval' in regex m/%s/
1979 (F) A regular expression contained the C<(?{ ... })> zero-width
1980 assertion, but that construct is only allowed when the C<use re 'eval'>
1981 pragma is in effect. See L<perlre/(?{ code })>.
1983 =item EVAL without pos change exceeded limit in regex; marked by
1984 S<<-- HERE> in m/%s/
1986 (F) You used a pattern that nested too many EVAL calls without consuming
1987 any text. Restructure the pattern so that text is consumed.
1989 The <-- HERE shows whereabouts in the regular expression the problem was
1992 =item Excessively long <> operator
1994 (F) The contents of a <> operator may not exceed the maximum size of a
1995 Perl identifier. If you're just trying to glob a long list of
1996 filenames, try using the glob() operator, or put the filenames into a
1997 variable and glob that.
1999 =item exec? I'm not *that* kind of operating system
2001 (F) The C<exec> function is not implemented on some systems, e.g., Symbian
2002 OS. See L<perlport>.
2004 =item Execution of %s aborted due to compilation errors.
2006 (F) The final summary message when a Perl compilation fails.
2008 =item exists argument is not a HASH or ARRAY element or a subroutine
2010 (F) The argument to C<exists> must be a hash or array element or a
2011 subroutine with an ampersand, such as:
2017 =item exists argument is not a subroutine name
2019 (F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
2020 and not a subroutine call. C<exists &sub()> will generate this error.
2022 =item Exiting eval via %s
2024 (W exiting) You are exiting an eval by unconventional means, such as a
2025 goto, or a loop control statement.
2027 =item Exiting format via %s
2029 (W exiting) You are exiting a format by unconventional means, such as a
2030 goto, or a loop control statement.
2032 =item Exiting pseudo-block via %s
2034 (W exiting) You are exiting a rather special block construct (like a
2035 sort block or subroutine) by unconventional means, such as a goto, or a
2036 loop control statement. See L<perlfunc/sort>.
2038 =item Exiting subroutine via %s
2040 (W exiting) You are exiting a subroutine by unconventional means, such
2041 as a goto, or a loop control statement.
2043 =item Exiting substitution via %s
2045 (W exiting) You are exiting a substitution by unconventional means, such
2046 as a return, a goto, or a loop control statement.
2048 =item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
2050 (F) You wrote something like
2054 to denote a capturing group of the form
2055 L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
2056 but omitted the C<")">.
2058 =item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
2060 (F) The C<(?[...])> extended character class regular expression construct
2061 only allows character classes (including character class escapes like
2062 C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
2063 containing at least one flag and exactly one C<(?[...])> construct.
2064 This allows a regular expression containing just C<(?[...])> to be
2065 interpolated. If you see this error message, then you probably
2066 have some other C<(?...)> construct inside your character class. See
2067 L<perlrecharclass/Extended Bracketed Character Classes>.
2069 =item Experimental aliasing via reference not enabled
2071 (F) To do aliasing via references, you must first enable the feature:
2073 no warnings "experimental::refaliasing";
2074 use feature "refaliasing";
2077 =item Experimental subroutine signatures not enabled
2079 (F) To use subroutine signatures, you must first enable them:
2081 no warnings "experimental::signatures";
2082 use feature "signatures";
2083 sub foo ($left, $right) { ... }
2085 =item Experimental "%s" subs not enabled
2087 (F) To use lexical subs, you must first enable them:
2089 no warnings 'experimental::lexical_subs';
2090 use feature 'lexical_subs';
2093 =item Explicit blessing to '' (assuming package main)
2095 (W misc) You are blessing a reference to a zero length string. This has
2096 the effect of blessing the reference into the package main. This is
2097 usually not what you want. Consider providing a default target package,
2098 e.g. bless($ref, $p || 'MyPackage');
2100 =item %s: Expression syntax
2102 (A) You've accidentally run your script through B<csh> instead of Perl.
2103 Check the #! line, or manually feed your script into Perl yourself.
2105 =item %s failed--call queue aborted
2107 (F) An untrapped exception was raised while executing a UNITCHECK,
2108 CHECK, INIT, or END subroutine. Processing of the remainder of the
2109 queue of such routines has been prematurely ended.
2111 =item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
2113 (W regexp)(F) A character class range must start and end at a literal
2114 character, not another character class like C<\d> or C<[:alpha:]>. The "-"
2115 in your false range is interpreted as a literal "-". In a C<(?[...])>
2116 construct, this is an error, rather than a warning. Consider quoting
2117 the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
2118 the problem was discovered. See L<perlre>.
2120 =item Fatal VMS error (status=%d) at %s, line %d
2122 (P) An error peculiar to VMS. Something untoward happened in a VMS
2123 system service or RTL routine; Perl's exit status should provide more
2124 details. The filename in "at %s" and the line number in "line %d" tell
2125 you which section of the Perl source code is distressed.
2127 =item fcntl is not implemented
2129 (F) Your machine apparently doesn't implement fcntl(). What is this, a
2130 PDP-11 or something?
2132 =item FETCHSIZE returned a negative value
2134 (F) A tied array claimed to have a negative number of elements, which
2137 =item Field too wide in 'u' format in pack
2139 (W pack) Each line in an uuencoded string starts with a length indicator
2140 which can't encode values above 63. So there is no point in asking for
2141 a line length bigger than that. Perl will behave as if you specified
2142 C<u63> as the format.
2144 =item Filehandle %s opened only for input
2146 (W io) You tried to write on a read-only filehandle. If you intended
2147 it to be a read-write filehandle, you needed to open it with "+<" or
2148 "+>" or "+>>" instead of with "<" or nothing. If you intended only to
2149 write the file, use ">" or ">>". See L<perlfunc/open>.
2151 =item Filehandle %s opened only for output
2153 (W io) You tried to read from a filehandle opened only for writing, If
2154 you intended it to be a read/write filehandle, you needed to open it
2155 with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2156 read from the file, use "<". See L<perlfunc/open>. Another possibility
2157 is that you attempted to open filedescriptor 0 (also known as STDIN) for
2158 output (maybe you closed STDIN earlier?).
2160 =item Filehandle %s reopened as %s only for input
2162 (W io) You opened for reading a filehandle that got the same filehandle id
2163 as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
2166 =item Filehandle STDIN reopened as %s only for output
2168 (W io) You opened for writing a filehandle that got the same filehandle id
2169 as STDIN. This occurred because you closed STDIN previously.
2171 =item Final $ should be \$ or $name
2173 (F) You must now decide whether the final $ in a string was meant to be
2174 a literal dollar sign, or was meant to introduce a variable name that
2175 happens to be missing. So you have to put either the backslash or the
2178 =item flock() on closed filehandle %s
2180 (W closed) The filehandle you're attempting to flock() got itself closed
2181 some time before now. Check your control flow. flock() operates on
2182 filehandles. Are you attempting to call flock() on a dirhandle by the
2185 =item Format not terminated
2187 (F) A format must be terminated by a line with a solitary dot. Perl got
2188 to the end of your file without finding such a line.
2190 =item Format %s redefined
2192 (W redefine) You redefined a format. To suppress this warning, say
2195 no warnings 'redefine';
2196 eval "format NAME =...";
2199 =item Found = in conditional, should be ==
2209 (or something like that).
2211 =item %s found where operator expected
2213 (S syntax) The Perl lexer knows whether to expect a term or an operator.
2214 If it sees what it knows to be a term when it was expecting to see an
2215 operator, it gives you this warning. Usually it indicates that an
2216 operator or delimiter was omitted, such as a semicolon.
2218 =item gdbm store returned %d, errno %d, key "%s"
2220 (S) A warning from the GDBM_File extension that a store failed.
2222 =item gethostent not implemented
2224 (F) Your C library apparently doesn't implement gethostent(), probably
2225 because if it did, it'd feel morally obligated to return every hostname
2228 =item get%sname() on closed socket %s
2230 (W closed) You tried to get a socket or peer socket name on a closed
2231 socket. Did you forget to check the return value of your socket() call?
2233 =item getpwnam returned invalid UIC %#o for user "%s"
2235 (S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2236 C<getpwnam> operator returned an invalid UIC.
2238 =item getsockopt() on closed socket %s
2240 (W closed) You tried to get a socket option on a closed socket. Did you
2241 forget to check the return value of your socket() call? See
2242 L<perlfunc/getsockopt>.
2244 =item given is experimental
2246 (S experimental::smartmatch) C<given> depends on smartmatch, which
2247 is experimental, so its behavior may change or even be removed
2248 in any future release of perl. See the explanation under
2249 L<perlsyn/Experimental Details on given and when>.
2251 =item Global symbol "%s" requires explicit package name (did you forget to
2254 (F) You've said "use strict" or "use strict vars", which indicates
2255 that all variables must either be lexically scoped (using "my" or "state"),
2256 declared beforehand using "our", or explicitly qualified to say
2257 which package the global variable is in (using "::").
2259 =item glob failed (%s)
2261 (S glob) Something went wrong with the external program(s) used
2262 for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2263 pattern that caused the external program to fail and exit with a
2264 nonzero status. If the message indicates that the abnormal exit
2265 resulted in a coredump, this may also mean that your csh (C shell)
2266 is broken. If so, you should change all of the csh-related variables
2267 in config.sh: If you have tcsh, make the variables refer to it as
2268 if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2269 all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
2270 think csh is missing. In either case, after editing config.sh, run
2271 C<./Configure -S> and rebuild Perl.
2273 =item Glob not terminated
2275 (F) The lexer saw a left angle bracket in a place where it was expecting
2276 a term, so it's looking for the corresponding right angle bracket, and
2277 not finding it. Chances are you left some needed parentheses out
2278 earlier in the line, and you really meant a "less than".
2280 =item gmtime(%f) failed
2282 (W overflow) You called C<gmtime> with a number that it could not handle:
2283 too large, too small, or NaN. The returned value is C<undef>.
2285 =item gmtime(%f) too large
2287 (W overflow) You called C<gmtime> with a number that was larger than
2288 it can reliably handle and C<gmtime> probably returned the wrong
2289 date. This warning is also triggered with NaN (the special
2290 not-a-number value).
2292 =item gmtime(%f) too small
2294 (W overflow) You called C<gmtime> with a number that was smaller than
2295 it can reliably handle and C<gmtime> probably returned the wrong date.
2297 =item Got an error from DosAllocMem
2299 (P) An error peculiar to OS/2. Most probably you're using an obsolete
2300 version of Perl, and this should not happen anyway.
2302 =item goto must have label
2304 (F) Unlike with "next" or "last", you're not allowed to goto an
2305 unspecified destination. See L<perlfunc/goto>.
2307 =item Goto undefined subroutine%s
2309 (F) You tried to call a subroutine with C<goto &sub> syntax, but
2310 the indicated subroutine hasn't been defined, or if it was, it
2311 has since been undefined.
2313 =item Group name must start with a non-digit word character in regex; marked by
2314 S<<-- HERE> in m/%s/
2316 (F) Group names must follow the rules for perl identifiers, meaning
2317 they must start with a non-digit word character. A common cause of
2318 this error is using (?&0) instead of (?0). See L<perlre>.
2320 =item ()-group starts with a count
2322 (F) A ()-group started with a count. A count is supposed to follow
2323 something: a template character or a ()-group. See L<perlfunc/pack>.
2325 =item %s had compilation errors.
2327 (F) The final summary message when a C<perl -c> fails.
2329 =item Had to create %s unexpectedly
2331 (S internal) A routine asked for a symbol from a symbol table that ought
2332 to have existed already, but for some reason it didn't, and had to be
2333 created on an emergency basis to prevent a core dump.
2335 =item %s has too many errors
2337 (F) The parser has given up trying to parse the program after 10 errors.
2338 Further error messages would likely be uninformative.
2340 =item Having more than one /%c regexp modifier is deprecated
2342 (D deprecated, regexp) You used the indicated regular expression pattern
2343 modifier at least twice in a string of modifiers. It is deprecated to
2344 do this with this particular modifier, to allow future extensions to the
2347 =item Hexadecimal float: exponent overflow
2349 (W overflow) The hexadecimal floating point has a larger exponent
2350 than the floating point supports.
2352 =item Hexadecimal float: exponent underflow
2354 (W overflow) The hexadecimal floating point has a smaller exponent
2355 than the floating point supports.
2357 =item Hexadecimal float: internal error
2359 (F) Something went horribly bad in hexadecimal float handling.
2361 =item Hexadecimal float: mantissa overflow
2363 (W overflow) The hexadecimal floating point literal had more bits in
2364 the mantissa (the part between the 0x and the exponent, also known as
2365 the fraction or the significand) than the floating point supports.
2367 =item Hexadecimal float: precision loss
2369 (W overflow) The hexadecimal floating point had internally more
2370 digits than could be output. This can be caused by unsupported
2371 long double formats, or by 64-bit integers not being available
2372 (needed to retrieve the digits under some configurations).
2374 =item Hexadecimal float: unsupported long double format
2376 (F) You have configured Perl to use long doubles but
2377 the internals of the long double format are unknown;
2378 therefore the hexadecimal float output is impossible.
2380 =item Hexadecimal number > 0xffffffff non-portable
2382 (W portable) The hexadecimal number you specified is larger than 2**32-1
2383 (4294967295) and therefore non-portable between systems. See
2384 L<perlport> for more on portability concerns.
2386 =item Identifier too long
2388 (F) Perl limits identifiers (names for variables, functions, etc.) to
2389 about 250 characters for simple names, and somewhat more for compound
2390 names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2391 of Perl are likely to eliminate these arbitrary limitations.
2393 =item Ignoring zero length \N{} in character class in regex; marked by
2394 S<<-- HERE> in m/%s/
2396 (W regexp) Named Unicode character escapes (C<\N{...}>) may return a
2397 zero-length sequence. When such an escape is used in a character
2398 class its behavior is not well defined. Check that the correct
2399 escape has been used, and the correct charname handler is in scope.
2401 =item Illegal binary digit %s
2403 (F) You used a digit other than 0 or 1 in a binary number.
2405 =item Illegal binary digit %s ignored
2407 (W digit) You may have tried to use a digit other than 0 or 1 in a
2408 binary number. Interpretation of the binary number stopped before the
2411 =item Illegal character after '_' in prototype for %s : %s
2413 (W illegalproto) An illegal character was found in a prototype
2414 declaration. The '_' in a prototype must be followed by a ';',
2415 indicating the rest of the parameters are optional, or one of '@'
2416 or '%', since those two will accept 0 or more final parameters.
2418 =item Illegal character \%o (carriage return)
2420 (F) Perl normally treats carriage returns in the program text as it
2421 would any other whitespace, which means you should never see this error
2422 when Perl was built using standard options. For some reason, your
2423 version of Perl appears to have been built without this support. Talk
2424 to your Perl administrator.
2426 =item Illegal character in prototype for %s : %s
2428 (W illegalproto) An illegal character was found in a prototype declaration.
2429 Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
2430 Perhaps you were trying to write a subroutine signature but didn't enable
2431 that feature first (C<use feature 'signatures'>), so your signature was
2432 instead interpreted as a bad prototype.
2434 =item Illegal declaration of anonymous subroutine
2436 (F) When using the C<sub> keyword to construct an anonymous subroutine,
2437 you must always specify a block of code. See L<perlsub>.
2439 =item Illegal declaration of subroutine %s
2441 (F) A subroutine was not declared correctly. See L<perlsub>.
2443 =item Illegal division by zero
2445 (F) You tried to divide a number by 0. Either something was wrong in
2446 your logic, or you need to put a conditional in to guard against
2449 =item Illegal hexadecimal digit %s ignored
2451 (W digit) You may have tried to use a character other than 0 - 9 or
2452 A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2453 number stopped before the illegal character.
2455 =item Illegal modulus zero
2457 (F) You tried to divide a number by 0 to get the remainder. Most
2458 numbers don't take to this kindly.
2460 =item Illegal number of bits in vec
2462 (F) The number of bits in vec() (the third argument) must be a power of
2463 two from 1 to 32 (or 64, if your platform supports that).
2465 =item Illegal octal digit %s
2467 (F) You used an 8 or 9 in an octal number.
2469 =item Illegal octal digit %s ignored
2471 (W digit) You may have tried to use an 8 or 9 in an octal number.
2472 Interpretation of the octal number stopped before the 8 or 9.
2474 =item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
2476 (F) You wrote something like
2480 The C<"+"> is valid only when followed by digits, indicating a
2481 capturing group. See
2482 L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2484 =item Illegal suidscript
2486 (F) The script run under suidperl was somehow illegal.
2488 =item Illegal switch in PERL5OPT: -%c
2490 (X) The PERL5OPT environment variable may only be used to set the
2491 following switches: B<-[CDIMUdmtw]>.
2493 =item Ill-formed CRTL environ value "%s"
2495 (W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
2496 internal environ array, and encountered an element without the C<=>
2497 delimiter used to separate keys from values. The element is ignored.
2499 =item Ill-formed message in prime_env_iter: |%s|
2501 (W internal) A warning peculiar to VMS. Perl tried to read a logical
2502 name or CLI symbol definition when preparing to iterate over %ENV, and
2503 didn't see the expected delimiter between key and value, so the line was
2506 =item (in cleanup) %s
2508 (W misc) This prefix usually indicates that a DESTROY() method raised
2509 the indicated exception. Since destructors are usually called by the
2510 system at arbitrary points during execution, and often a vast number of
2511 times, the warning is issued only once for any number of failures that
2512 would otherwise result in the same message being repeated.
2514 Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2515 also result in this warning. See L<perlcall/G_KEEPERR>.
2517 =item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2520 (F) There was a syntax error within the C<(?[ ])>. This can happen if the
2521 expression inside the construct was completely empty, or if there are
2522 too many or few operands for the number of operators. Perl is not smart
2523 enough to give you a more precise indication as to what is wrong.
2525 =item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2528 (F) The method resolution order (MRO) of the given class is not
2529 C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2530 documentation in L<mro> for more information.
2532 =item In EBCDIC the v-string components cannot exceed 2147483647
2534 (F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2535 Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2536 encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2538 =item Infinite recursion in regex
2540 (F) You used a pattern that references itself without consuming any input
2541 text. You should check the pattern to ensure that recursive patterns
2542 either consume text or fail.
2544 =item Initialization of state variables in list context currently forbidden
2546 (F) Currently the implementation of "state" only permits the
2547 initialization of scalar variables in scalar context. Re-write
2548 C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2549 context. Constructions such as C<state (@a) = foo()> will be
2550 supported in a future perl release.
2552 =item %%s[%s] in scalar context better written as $%s[%s]
2554 (W syntax) In scalar context, you've used an array index/value slice
2555 (indicated by %) to select a single element of an array. Generally
2556 it's better to ask for a scalar value (indicated by $). The difference
2557 is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2558 returns and when evaluating its argument, while C<%foo[&bar]> provides
2559 a list context to its subscript, which can do weird things if you're
2560 expecting only one subscript. When called in list context, it also
2561 returns the index (what C<&bar> returns) in addition to the value.
2563 =item %%s{%s} in scalar context better written as $%s{%s}
2565 (W syntax) In scalar context, you've used a hash key/value slice
2566 (indicated by %) to select a single element of a hash. Generally it's
2567 better to ask for a scalar value (indicated by $). The difference
2568 is that C<$foo{&bar}> always behaves like a scalar, both in the value
2569 it returns and when evaluating its argument, while C<@foo{&bar}> and
2570 provides a list context to its subscript, which can do weird things
2571 if you're expecting only one subscript. When called in list context,
2572 it also returns the key in addition to the value.
2574 =item Insecure dependency in %s
2576 (F) You tried to do something that the tainting mechanism didn't like.
2577 The tainting mechanism is turned on when you're running setuid or
2578 setgid, or when you specify B<-T> to turn it on explicitly. The
2579 tainting mechanism labels all data that's derived directly or indirectly
2580 from the user, who is considered to be unworthy of your trust. If any
2581 such data is used in a "dangerous" operation, you get this error. See
2582 L<perlsec> for more information.
2584 =item Insecure directory in %s
2586 (F) You can't use system(), exec(), or a piped open in a setuid or
2587 setgid script if C<$ENV{PATH}> contains a directory that is writable by
2588 the world. Also, the PATH must not contain any relative directory.
2591 =item Insecure $ENV{%s} while running %s
2593 (F) You can't use system(), exec(), or a piped open in a setuid or
2594 setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
2595 C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2596 supplied (or potentially supplied) by the user. The script must set
2597 the path to a known value, using trustworthy data. See L<perlsec>.
2599 =item Insecure user-defined property %s
2601 (F) Perl detected tainted data when trying to compile a regular
2602 expression that contains a call to a user-defined character property
2603 function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2604 See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2606 =item Integer overflow in format string for %s
2608 (F) The indexes and widths specified in the format string of C<printf()>
2609 or C<sprintf()> are too large. The numbers must not overflow the size of
2610 integers for your architecture.
2612 =item Integer overflow in %s number
2614 (S overflow) The hexadecimal, octal or binary number you have specified
2615 either as a literal or as an argument to hex() or oct() is too big for
2616 your architecture, and has been converted to a floating point number.
2617 On a 32-bit architecture the largest hexadecimal, octal or binary number
2618 representable without overflow is 0xFFFFFFFF, 037777777777, or
2619 0b11111111111111111111111111111111 respectively. Note that Perl
2620 transparently promotes all numbers to a floating point representation
2621 internally--subject to loss of precision errors in subsequent
2624 =item Integer overflow in srand
2626 (S overflow) The number you have passed to srand is too big to fit
2627 in your architecture's integer representation. The number has been
2628 replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2629 architectures). This means you may be getting less randomness than
2630 you expect, because different random seeds above the maximum will
2631 return the same sequence of random numbers.
2633 =item Integer overflow in version
2635 =item Integer overflow in version %d
2637 (W overflow) Some portion of a version initialization is too large for
2638 the size of integers for your architecture. This is not a warning
2639 because there is no rational reason for a version to try and use an
2640 element larger than typically 2**32. This is usually caused by trying
2641 to use some odd mathematical operation as a version, like 100/9.
2643 =item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
2645 (P) Something went badly wrong in the regular expression parser.
2646 The S<<-- HERE> shows whereabouts in the regular expression the problem was
2649 =item Internal inconsistency in tracking vforks
2651 (S) A warning peculiar to VMS. Perl keeps track of the number of times
2652 you've called C<fork> and C<exec>, to determine whether the current call
2653 to C<exec> should affect the current script or a subprocess (see
2654 L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2655 Perl is making a guess and treating this C<exec> as a request to
2656 terminate the Perl script and execute the specified command.
2658 =item internal %<num>p might conflict with future printf extensions
2660 (S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2661 formatting follows a slightly different set of rules when called from
2662 C or XS code. Specifically, formats consisting of digits followed
2663 by "p" (e.g., "%7p") are reserved for future use. If you see this
2664 message, then an XS module tried to call that routine with one such
2667 =item Internal urp in regex; marked by S<<-- HERE> in m/%s/
2669 (P) Something went badly awry in the regular expression parser. The
2670 S<<-- HERE> shows whereabouts in the regular expression the problem was
2673 =item %s (...) interpreted as function
2675 (W syntax) You've run afoul of the rule that says that any list operator
2676 followed by parentheses turns into a function, with all the list
2677 operators arguments found inside the parentheses. See
2678 L<perlop/Terms and List Operators (Leftward)>.
2680 =item In '(?...)', the '(' and '?' must be adjacent in regex;
2681 marked by S<<-- HERE> in m/%s/
2683 (F) The two-character sequence C<"(?"> in this context in a regular
2684 expression pattern should be an indivisible token, with nothing
2685 intervening between the C<"("> and the C<"?">, but you separated them
2688 =item Invalid %s attribute: %s
2690 (F) The indicated attribute for a subroutine or variable was not recognized
2691 by Perl or by a user-supplied handler. See L<attributes>.
2693 =item Invalid %s attributes: %s
2695 (F) The indicated attributes for a subroutine or variable were not
2696 recognized by Perl or by a user-supplied handler. See L<attributes>.
2698 =item Invalid character in charnames alias definition; marked by
2701 (F) You tried to create a custom alias for a character name, with
2702 the C<:alias> option to C<use charnames> and the specified character in
2703 the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2705 =item Invalid \0 character in %s for %s: %s\0%s
2707 (W syscalls) Embedded \0 characters in pathnames or other system call
2708 arguments produce a warning as of 5.20. The parts after the \0 were
2709 formerly ignored by system calls.
2711 =item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
2713 (F) Only certain characters are valid for character names. The
2714 indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2716 =item Invalid conversion in %s: "%s"
2718 (W printf) Perl does not understand the given format conversion. See
2719 L<perlfunc/sprintf>.
2721 =item Invalid escape in the specified encoding in regex; marked by
2722 S<<-- HERE> in m/%s/
2724 (W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
2725 didn't correspond to a single character through the conversion
2726 from the encoding specified by the encoding pragma.
2727 The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2728 instead, except within S<C<(?[ ])>>, where it is a fatal error.
2729 The S<<-- HERE> shows whereabouts in the regular expression the
2730 escape was discovered.
2732 =item %s: Invalid handshake key got %p needed %p, binaries are mismatched
2734 (P) A dynamic loading library C<.so> or C<.dll> was being loaded into the
2735 process that was built against a different build of perl than the
2736 said library was compiled against. Reinstalling the XS module will
2737 likely fix this error.
2739 =item Invalid hexadecimal number in \N{U+...}
2741 =item Invalid hexadecimal number in \N{U+...} in regex; marked by
2742 S<<-- HERE> in m/%s/
2744 (F) The character constant represented by C<...> is not a valid hexadecimal
2745 number. Either it is empty, or you tried to use a character other than
2746 0 - 9 or A - F, a - f in a hexadecimal number.
2748 =item Invalid module name %s with -%c option: contains single ':'
2750 (F) The module argument to perl's B<-m> and B<-M> command-line options
2751 cannot contain single colons in the module name, but only in the
2752 arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2753 B<-MFoo:Bar=baz> is not.
2755 =item Invalid mro name: '%s'
2757 (F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2758 where C<foo> is not a valid method resolution order (MRO). Currently,
2759 the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2760 a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2762 =item Invalid negative number (%s) in chr
2764 (W utf8) You passed a negative number to C<chr>. Negative numbers are
2765 not valid character numbers, so it returns the Unicode replacement
2768 =item invalid option -D%c, use -D'' to see choices
2770 (S debugging) Perl was called with invalid debugger flags. Call perl
2771 with the B<-D> option with no flags to see the list of acceptable values.
2772 See also L<perlrun/-Dletters>.
2774 =item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
2776 (F) The range specified in a character class had a minimum character
2777 greater than the maximum character. One possibility is that you forgot the
2778 C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
2779 up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
2780 problem was discovered. See L<perlre>.
2782 =item Invalid range "%s" in transliteration operator
2784 (F) The range specified in the tr/// or y/// operator had a minimum
2785 character greater than the maximum character. See L<perlop>.
2787 =item Invalid separator character %s in attribute list
2789 (F) Something other than a colon or whitespace was seen between the
2790 elements of an attribute list. If the previous attribute had a
2791 parenthesised parameter list, perhaps that list was terminated too soon.
2794 =item Invalid separator character %s in PerlIO layer specification %s
2796 (W layer) When pushing layers onto the Perl I/O system, something other
2797 than a colon or whitespace was seen between the elements of a layer list.
2798 If the previous attribute had a parenthesised parameter list, perhaps that
2799 list was terminated too soon.
2801 =item Invalid strict version format (%s)
2803 (F) A version number did not meet the "strict" criteria for versions.
2804 A "strict" version number is a positive decimal number (integer or
2805 decimal-fraction) without exponentiation or else a dotted-decimal
2806 v-string with a leading 'v' character and at least three components.
2807 The parenthesized text indicates which criteria were not met.
2808 See the L<version> module for more details on allowed version formats.
2810 =item Invalid type '%s' in %s
2812 (F) The given character is not a valid pack or unpack type.
2813 See L<perlfunc/pack>.
2815 (W) The given character is not a valid pack or unpack type but used to be
2818 =item Invalid version format (%s)
2820 (F) A version number did not meet the "lax" criteria for versions.
2821 A "lax" version number is a positive decimal number (integer or
2822 decimal-fraction) without exponentiation or else a dotted-decimal
2823 v-string. If the v-string has fewer than three components, it
2824 must have a leading 'v' character. Otherwise, the leading 'v' is
2825 optional. Both decimal and dotted-decimal versions may have a
2826 trailing "alpha" component separated by an underscore character
2827 after a fractional or dotted-decimal component. The parenthesized
2828 text indicates which criteria were not met. See the L<version> module
2829 for more details on allowed version formats.
2831 =item Invalid version object
2833 (F) The internal structure of the version object was invalid.
2834 Perhaps the internals were modified directly in some way or
2835 an arbitrary reference was blessed into the "version" class.
2837 =item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
2838 marked by S<<-- HERE> in m/%s/
2840 (F) The two-character sequence C<"(*"> in
2841 this context in a regular expression pattern should be an
2842 indivisible token, with nothing intervening between the C<"(">
2843 and the C<"*">, but you separated them.
2845 =item ioctl is not implemented
2847 (F) Your machine apparently doesn't implement ioctl(), which is pretty
2848 strange for a machine that supports C.
2850 =item ioctl() on unopened %s
2852 (W unopened) You tried ioctl() on a filehandle that was never opened.
2853 Check your control flow and number of arguments.
2855 =item IO layers (like '%s') unavailable
2857 (F) Your Perl has not been configured to have PerlIO, and therefore
2858 you cannot use IO layers. To have PerlIO, Perl must be configured
2861 =item IO::Socket::atmark not implemented on this architecture
2863 (F) Your machine doesn't implement the sockatmark() functionality,
2864 neither as a system call nor an ioctl call (SIOCATMARK).
2866 =item $* is no longer supported
2868 (D deprecated, syntax) The special variable C<$*>, deprecated in older
2869 perls, has been removed as of 5.10.0 and is no longer supported. In
2870 previous versions of perl the use of C<$*> enabled or disabled multi-line
2871 matching within a string.
2873 Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
2874 modifiers. You can enable C</m> for a lexical scope (even a whole file)
2875 with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
2876 then all regular expressions behaved as if they were written using C</m>.)
2878 =item $# is no longer supported
2880 (D deprecated, syntax) The special variable C<$#>, deprecated in older
2881 perls, has been removed as of 5.10.0 and is no longer supported. You
2882 should use the printf/sprintf functions instead.
2884 =item '%s' is not a code reference
2886 (W overload) The second (fourth, sixth, ...) argument of
2887 overload::constant needs to be a code reference. Either
2888 an anonymous subroutine, or a reference to a subroutine.
2890 =item '%s' is not an overloadable type
2892 (W overload) You tried to overload a constant type the overload package is
2895 =item -i used with no filenames on the command line, reading from STDIN
2897 (S inplace) The C<-i> option was passed on the command line, indicating
2898 that the script is intended to edit files in place, but no files were
2899 given. This is usually a mistake, since editing STDIN in place doesn't
2900 make sense, and can be confusing because it can make perl look like
2901 it is hanging when it is really just trying to read from STDIN. You
2902 should either pass a filename to edit, or remove C<-i> from the command
2903 line. See L<perlrun> for more details.
2905 =item Junk on end of regexp in regex m/%s/
2907 (P) The regular expression parser is confused.
2909 =item keys on reference is experimental
2911 (S experimental::autoderef) C<keys> with a scalar argument is experimental
2912 and may change or be removed in a future Perl version. If you want to
2913 take the risk of using this feature, simply disable this warning:
2915 no warnings "experimental::autoderef";
2917 =item Label not found for "last %s"
2919 (F) You named a loop to break out of, but you're not currently in a loop
2920 of that name, not even if you count where you were called from. See
2923 =item Label not found for "next %s"
2925 (F) You named a loop to continue, but you're not currently in a loop of
2926 that name, not even if you count where you were called from. See
2929 =item Label not found for "redo %s"
2931 (F) You named a loop to restart, but you're not currently in a loop of
2932 that name, not even if you count where you were called from. See
2935 =item leaving effective %s failed
2937 (F) While under the C<use filetest> pragma, switching the real and
2938 effective uids or gids failed.
2940 =item length/code after end of string in unpack
2942 (F) While unpacking, the string buffer was already used up when an unpack
2943 length/code combination tried to obtain more data. This results in
2944 an undefined value for the length. See L<perlfunc/pack>.
2946 =item length() used on %s (did you mean "scalar(%s)"?)
2948 (W syntax) You used length() on either an array or a hash when you
2949 probably wanted a count of the items.
2951 Array size can be obtained by doing:
2955 The number of items in a hash can be obtained by doing:
2959 =item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2961 (F) An extension is attempting to insert text into the current parse
2962 (using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2963 couldn't be part of the current input. This is an inherent pitfall
2964 of the stuffing mechanism, and one of the reasons to avoid it. Where
2965 it is necessary to stuff, stuffing only plain ASCII is recommended.
2967 =item Lexing code internal error (%s)
2969 (F) Lexing code supplied by an extension violated the lexer's API in a
2972 =item listen() on closed socket %s
2974 (W closed) You tried to do a listen on a closed socket. Did you forget
2975 to check the return value of your socket() call? See
2978 =item List form of piped open not implemented
2980 (F) On some platforms, notably Windows, the three-or-more-arguments
2981 form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2982 Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2984 =item localtime(%f) failed
2986 (W overflow) You called C<localtime> with a number that it could not handle:
2987 too large, too small, or NaN. The returned value is C<undef>.
2989 =item localtime(%f) too large
2991 (W overflow) You called C<localtime> with a number that was larger
2992 than it can reliably handle and C<localtime> probably returned the
2993 wrong date. This warning is also triggered with NaN (the special
2994 not-a-number value).
2996 =item localtime(%f) too small
2998 (W overflow) You called C<localtime> with a number that was smaller
2999 than it can reliably handle and C<localtime> probably returned the
3002 =item Locale '%s' may not work well.%s
3004 (W locale) The named locale that Perl is now trying to use is not fully
3005 compatible with Perl. The second C<%s> gives a reason.
3007 By far the most common reason is that the locale has characters in it
3008 that are represented by more than one byte. The only such locales that
3009 Perl can handle are the UTF-8 locales. Most likely the specified locale
3010 is a non-UTF-8 one for an East Asian language such as Chinese or
3011 Japanese. If the locale is a superset of ASCII, the ASCII portion of it
3012 may work in Perl. Read on for problems when it isn't a superset of
3015 Some essentially obsolete locales that aren't supersets of ASCII, mainly
3016 those in ISO 646 or other 7-bit locales, such as ASMO 449, can also have
3017 problems, depending on what portions of the ASCII character set get
3018 changed by the locale and are also used by the program.
3019 The warning message lists the determinable conflicting characters.
3021 =item Lookbehind longer than %d not implemented in regex m/%s/
3023 (F) There is currently a limit on the length of string which lookbehind can
3024 handle. This restriction may be eased in a future release.
3026 =item Lost precision when %s %f by 1
3028 (W imprecision) The value you attempted to increment or decrement by one
3029 is too large for the underlying floating point representation to store
3030 accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
3031 warning because it has already switched from integers to floating point
3032 when values are too large for integers, and now even floating point is
3033 insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
3035 =item lstat() on filehandle%s
3037 (W io) You tried to do an lstat on a filehandle. What did you mean
3038 by that? lstat() makes sense only on filenames. (Perl did a fstat()
3039 instead on the filehandle.)
3041 =item lvalue attribute %s already-defined subroutine
3043 (W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
3044 attribute on or off on a Perl subroutine that is already defined
3045 does not always work properly. It may or may not do what you
3046 want, depending on what code is inside the subroutine, with exact
3047 details subject to change between Perl versions. Only do this
3048 if you really know what you are doing.
3050 =item lvalue attribute ignored after the subroutine has been defined
3052 (W misc) Using the C<:lvalue> declarative syntax to make a Perl
3053 subroutine an lvalue subroutine after it has been defined is
3054 not permitted. To make the subroutine an lvalue subroutine,
3055 add the lvalue attribute to the definition, or put the C<sub
3056 foo :lvalue;> declaration before the definition.
3058 See also L<attributes.pm|attributes>.
3060 =item Magical list constants are not supported
3062 (F) You assigned a magical array to a stash element, and then tried
3063 to use the subroutine from the same slot. You are asking Perl to do
3064 something it cannot do, details subject to change between Perl versions.
3066 =item Malformed integer in [] in pack
3068 (F) Between the brackets enclosing a numeric repeat count only digits
3069 are permitted. See L<perlfunc/pack>.
3071 =item Malformed integer in [] in unpack
3073 (F) Between the brackets enclosing a numeric repeat count only digits
3074 are permitted. See L<perlfunc/pack>.
3076 =item Malformed PERLLIB_PREFIX
3078 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
3085 with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
3086 a builtin library search path, prefix2 is substituted. The error may
3087 appear if components are not found, or are too long. See
3088 "PERLLIB_PREFIX" in L<perlos2>.
3090 =item Malformed prototype for %s: %s
3092 (F) You tried to use a function with a malformed prototype. The
3093 syntax of function prototypes is given a brief compile-time check for
3094 obvious errors like invalid characters. A more rigorous check is run
3095 when the function is called.
3096 Perhaps the function's author was trying to write a subroutine signature
3097 but didn't enable that feature first (C<use feature 'signatures'>),
3098 so the signature was instead interpreted as a bad prototype.
3100 =item Malformed UTF-8 character (%s)
3102 (S utf8)(F) Perl detected a string that didn't comply with UTF-8
3103 encoding rules, even though it had the UTF8 flag on.
3105 One possible cause is that you set the UTF8 flag yourself for data that
3106 you thought to be in UTF-8 but it wasn't (it was for example legacy
3107 8-bit data). To guard against this, you can use Encode::decode_utf8.
3109 If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
3110 sequences are handled gracefully, but if you use C<:utf8>, the flag is
3111 set without validating the data, possibly resulting in this error
3114 See also L<Encode/"Handling Malformed Data">.
3116 =item Malformed UTF-8 character immediately after '%s'
3118 (F) You said C<use utf8>, but the program file doesn't comply with UTF-8
3119 encoding rules. The message prints out the properly encoded characters
3120 just before the first bad one. If C<utf8> warnings are enabled, a
3121 warning is generated that gives more details about the type of
3124 =item Malformed UTF-8 returned by \N{%s} immediately after '%s'
3126 (F) The charnames handler returned malformed UTF-8.
3128 =item Malformed UTF-8 string in '%c' format in unpack
3130 (F) You tried to unpack something that didn't comply with UTF-8 encoding
3131 rules and perl was unable to guess how to make more progress.
3133 =item Malformed UTF-8 string in pack
3135 (F) You tried to pack something that didn't comply with UTF-8 encoding
3136 rules and perl was unable to guess how to make more progress.
3138 =item Malformed UTF-8 string in unpack
3140 (F) You tried to unpack something that didn't comply with UTF-8 encoding
3141 rules and perl was unable to guess how to make more progress.
3143 =item Malformed UTF-16 surrogate
3145 (F) Perl thought it was reading UTF-16 encoded character data but while
3146 doing it Perl met a malformed Unicode surrogate.
3148 =item Mandatory parameter follows optional parameter
3150 (F) In a subroutine signature, you wrote something like "$a = undef,
3151 $b", making an earlier parameter optional and a later one mandatory.
3152 Parameters are filled from left to right, so it's impossible for the
3153 caller to omit an earlier one and pass a later one. If you want to act
3154 as if the parameters are filled from right to left, declare the rightmost
3155 optional and then shuffle the parameters around in the subroutine's body.
3157 =item Matched non-Unicode code point 0x%X against Unicode property; may
3160 (S non_unicode) Perl allows strings to contain a superset of
3161 Unicode code points; each code point may be as large as what is storable
3162 in an unsigned integer on your system, but these may not be accepted by
3163 other languages/systems. This message occurs when you matched a string
3164 containing such a code point against a regular expression pattern, and
3165 the code point was matched against a Unicode property, C<\p{...}> or
3166 C<\P{...}>. Unicode properties are only defined on Unicode code points,
3167 so the result of this match is undefined by Unicode, but Perl (starting
3168 in v5.20) treats non-Unicode code points as if they were typical
3169 unassigned Unicode ones, and matched this one accordingly. Whether a
3170 given property matches these code points or not is specified in
3171 L<perluniprops/Properties accessible through \p{} and \P{}>.
3173 This message is suppressed (unless it has been made fatal) if it is
3174 immaterial to the results of the match if the code point is Unicode or
3175 not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
3176 the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
3177 Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
3178 every code point except these 22.)
3180 Getting this message indicates that the outcome of the match arguably
3181 should have been the opposite of what actually happened. If you think
3182 that is the case, you may wish to make the C<non_unicode> warnings
3183 category fatal; if you agree with Perl's decision, you may wish to turn
3186 See L<perlunicode/Beyond Unicode code points> for more information.
3188 =item %s matches null string many times in regex; marked by S<<-- HERE> in
3191 (W regexp) The pattern you've specified would be an infinite loop if the
3192 regular expression engine didn't specifically check for that. The S<<-- HERE>
3193 shows whereabouts in the regular expression the problem was discovered.
3196 =item Maximal count of pending signals (%u) exceeded
3198 (F) Perl aborted due to too high a number of signals pending. This
3199 usually indicates that your operating system tried to deliver signals
3200 too fast (with a very high priority), starving the perl process from
3201 resources it would need to reach a point where it can process signals
3202 safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
3204 =item "%s" may clash with future reserved word
3206 (W) This warning may be due to running a perl5 script through a perl4
3207 interpreter, especially if the word that is being warned about is
3210 =item '%' may not be used in pack
3212 (F) You can't pack a string by supplying a checksum, because the
3213 checksumming process loses information, and you can't go the other way.
3214 See L<perlfunc/unpack>.
3216 =item Method for operation %s not found in package %s during blessing
3218 (F) An attempt was made to specify an entry in an overloading table that
3219 doesn't resolve to a valid subroutine. See L<overload>.
3221 =item Method %s not permitted
3225 =item Might be a runaway multi-line %s string starting on line %d
3227 (S) An advisory indicating that the previous error may have been caused
3228 by a missing delimiter on a string or pattern, because it eventually
3229 ended earlier on the current line.
3231 =item Misplaced _ in number
3233 (W syntax) An underscore (underbar) in a numeric constant did not
3234 separate two digits.
3236 =item Missing argument in %s
3238 (W missing) You called a function with fewer arguments than other
3239 arguments you supplied indicated would be needed.
3241 Currently only emitted when a printf-type format required more
3242 arguments than were supplied, but might be used in the future for
3243 other cases where we can statically determine that arguments to
3244 functions are missing, e.g. for the L<perlfunc/pack> function.
3246 =item Missing argument to -%c
3248 (F) The argument to the indicated command line switch must follow
3249 immediately after the switch, without intervening spaces.
3251 =item Missing braces on \N{}
3253 =item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
3255 (F) Wrong syntax of character name literal C<\N{charname}> within
3256 double-quotish context. This can also happen when there is a space
3257 (or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3258 This modifier does not change the requirement that the brace immediately
3261 =item Missing braces on \o{}
3263 (F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3265 =item Missing comma after first argument to %s function
3267 (F) While certain functions allow you to specify a filehandle or an
3268 "indirect object" before the argument list, this ain't one of them.
3270 =item Missing command in piped open
3272 (W pipe) You used the C<open(FH, "| command")> or
3273 C<open(FH, "command |")> construction, but the command was missing or
3276 =item Missing control char name in \c
3278 (F) A double-quoted string ended with "\c", without the required control
3281 =item Missing ']' in prototype for %s : %s
3283 (W illegalproto) A grouping was started with C<[> but never closed with C<]>.
3285 =item Missing name in "%s sub"
3287 (F) The syntax for lexically scoped subroutines requires that
3288 they have a name with which they can be found.
3290 =item Missing $ on loop variable
3292 (F) Apparently you've been programming in B<csh> too much. Variables
3293 are always mentioned with the $ in Perl, unlike in the shells, where it
3294 can vary from one line to the next.
3296 =item (Missing operator before %s?)
3298 (S syntax) This is an educated guess made in conjunction with the message
3299 "%s found where operator expected". Often the missing operator is a comma.
3301 =item Missing or undefined argument to require
3303 (F) You tried to call require with no argument or with an undefined
3304 value as an argument. Require expects either a package name or a
3305 file-specification as an argument. See L<perlfunc/require>.
3307 =item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
3309 (F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3311 =item Missing right brace on \N{} or unescaped left brace after \N
3313 (F) C<\N> has two meanings.
3315 The traditional one has it followed by a name enclosed in braces,
3316 meaning the character (or sequence of characters) given by that
3317 name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
3318 double-quoted strings and regular expression patterns. In patterns,
3319 it doesn't have the meaning an unescaped C<*> does.
3321 Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3322 in patterns, namely to match a non-newline character. (This is short
3323 for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3325 This can lead to some ambiguities. When C<\N> is not followed immediately
3326 by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3327 form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3328 means to match the given quantity of non-newlines (in these examples,
3329 3; and 5 or more, respectively). In all other case, where there is a
3330 C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3332 However, if there is no matching C<}>, Perl doesn't know if it was
3333 mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3334 If you meant the former, add the right brace; if you meant the latter,
3335 escape the brace with a backslash, like so: C<\N\{>
3337 =item Missing right curly or square bracket
3339 (F) The lexer counted more opening curly or square brackets than closing
3340 ones. As a general rule, you'll find it's missing near the place you
3343 =item (Missing semicolon on previous line?)
3345 (S syntax) This is an educated guess made in conjunction with the message
3346 "%s found where operator expected". Don't automatically put a semicolon on
3347 the previous line just because you saw this message.
3349 =item Modification of a read-only value attempted
3351 (F) You tried, directly or indirectly, to change the value of a
3352 constant. You didn't, of course, try "2 = 1", because the compiler
3353 catches that. But an easy way to do the same thing is:
3355 sub mod { $_[0] = 1 }
3358 Another way is to assign to a substr() that's off the end of the string.
3360 Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3361 is aliased to a constant in the look I<LIST>:
3364 foreach my $n ($x, 2) {
3365 $n *= 2; # modifies the $x, but fails on attempt to
3368 =item Modification of non-creatable array value attempted, %s
3370 (F) You tried to make an array value spring into existence, and the
3371 subscript was probably negative, even counting from end of the array
3374 =item Modification of non-creatable hash value attempted, %s
3376 (P) You tried to make a hash value spring into existence, and it
3377 couldn't be created for some peculiar reason.
3379 =item Module name must be constant
3381 (F) Only a bare module name is allowed as the first argument to a "use".
3383 =item Module name required with -%c option
3385 (F) The C<-M> or C<-m> options say that Perl should load some module, but
3386 you omitted the name of the module. Consult L<perlrun> for full details
3387 about C<-M> and C<-m>.
3389 =item More than one argument to '%s' open
3391 (F) The C<open> function has been asked to open multiple files. This
3392 can happen if you are trying to open a pipe to a command that takes a
3393 list of arguments, but have forgotten to specify a piped open mode.
3394 See L<perlfunc/open> for details.
3396 =item mprotect for COW string %p %u failed with %d
3398 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3399 L<perlguts/"Copy on Write">), but a shared string buffer
3400 could not be made read-only.
3402 =item mprotect for %p %u failed with %d
3404 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3405 but an op tree could not be made read-only.
3407 =item mprotect RW for COW string %p %u failed with %d
3409 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3410 L<perlguts/"Copy on Write">), but a read-only shared string
3411 buffer could not be made mutable.
3413 =item mprotect RW for %p %u failed with %d
3415 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
3416 L<perlhacktips>), but a read-only op tree could not be made
3417 mutable before freeing the ops.
3419 =item msg%s not implemented
3421 (F) You don't have System V message IPC on your system.
3423 =item Multidimensional syntax %s not supported
3425 (W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3426 They're written like C<$foo[1][2][3]>, as in C.
3428 =item '/' must follow a numeric type in unpack
3430 (F) You had an unpack template that contained a '/', but this did not
3431 follow some unpack specification producing a numeric value.
3432 See L<perlfunc/pack>.
3434 =item "my sub" not yet implemented
3436 (F) Lexically scoped subroutines are not yet implemented. Don't try
3439 =item "my" subroutine %s can't be in a package
3441 (F) Lexically scoped subroutines aren't in a package, so it doesn't make
3442 sense to try to declare one with a package qualifier on the front.
3444 =item "my %s" used in sort comparison
3446 (W syntax) The package variables $a and $b are used for sort comparisons.
3447 You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3448 sort comparison block, and the variable had earlier been declared as a
3449 lexical variable. Either qualify the sort variable with the package
3450 name, or rename the lexical variable.
3452 =item "my" variable %s can't be in a package
3454 (F) Lexically scoped variables aren't in a package, so it doesn't make
3455 sense to try to declare one with a package qualifier on the front. Use
3456 local() if you want to localize a package variable.
3458 =item Name "%s::%s" used only once: possible typo
3460 (W once) Typographical errors often show up as unique variable
3461 names. If you had a good reason for having a unique name, then
3462 just mention it again somehow to suppress the message. The C<our>
3463 declaration is also provided for this purpose.
3465 NOTE: This warning detects package symbols that have been used
3466 only once. This means lexical variables will never trigger this
3467 warning. It also means that all of the package variables $c, @c,
3468 %c, as well as *c, &c, sub c{}, c(), and c (the filehandle or
3469 format) are considered the same; if a program uses $c only once
3470 but also uses any of the others it will not trigger this warning.
3471 Symbols beginning with an underscore and symbols using special
3472 identifiers (q.v. L<perldata>) are exempt from this warning.
3474 =item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
3476 (F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3477 exactly 3 digits long. This helps catch some ambiguities. If your
3478 constant is too short, add leading zeros, like
3480 (?[ [ \078 ] ]) # Syntax error!
3481 (?[ [ \0078 ] ]) # Works
3482 (?[ [ \007 8 ] ]) # Clearer
3484 The maximum number this construct can express is C<\777>. If you
3485 need a larger one, you need to use L<\o{}|perlrebackslash/Octal escapes> instead. If you meant
3486 two separate things, you need to separate them:
3488 (?[ [ \7776 ] ]) # Syntax error!
3489 (?[ [ \o{7776} ] ]) # One meaning
3490 (?[ [ \777 6 ] ]) # Another meaning
3491 (?[ [ \777 \006 ] ]) # Still another
3493 =item Negative '/' count in unpack
3495 (F) The length count obtained from a length/code unpack operation was
3496 negative. See L<perlfunc/pack>.
3498 =item Negative length
3500 (F) You tried to do a read/write/send/recv operation with a buffer
3501 length that is less than 0. This is difficult to imagine.
3503 =item Negative offset to vec in lvalue context
3505 (F) When C<vec> is called in an lvalue context, the second argument must be
3506 greater than or equal to zero.
3508 =item Negative repeat count does nothing
3510 (W numeric) You tried to execute the
3511 L<C<x>|perlop/Multiplicative Operators> repetition operator fewer than 0
3512 times, which doesn't make sense.
3514 =item Nested quantifiers in regex; marked by S<<-- HERE> in m/%s/
3516 (F) You can't quantify a quantifier without intervening parentheses.
3517 So things like ** or +* or ?* are illegal. The S<<-- HERE> shows
3518 whereabouts in the regular expression the problem was discovered.
3520 Note that the minimal matching quantifiers, C<*?>, C<+?>, and
3521 C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
3523 =item %s never introduced
3525 (S internal) The symbol in question was declared but somehow went out of
3526 scope before it could possibly have been used.
3528 =item next::method/next::can/maybe::next::method cannot find enclosing method
3530 (F) C<next::method> needs to be called within the context of a
3531 real method in a real package, and it could not find such a context.
3534 =item \N in a character class must be a named character: \N{...} in regex;
3535 marked by S<<-- HERE> in m/%s/
3537 (F) The new (as of Perl 5.12) meaning of C<\N> as C<[^\n]> is not valid in a
3538 bracketed character class, for the same reason that C<.> in a character
3539 class loses its specialness: it matches almost everything, which is
3540 probably not what you want.
3542 =item \N{} in inverted character class or as a range end-point is restricted to one character in regex; marked
3543 by S<<-- HERE> in m/%s/
3545 (F) Named Unicode character escapes (C<\N{...}>) may return a
3546 multi-character sequence. Even though a character class is
3547 supposed to match just one character of input, perl will match the
3548 whole thing correctly, except when the class is inverted (C<[^...]>),
3549 or the escape is the beginning or final end point of a range. The
3550 mathematically logical behavior for what matches when inverting
3551 is very different from what people expect, so we have decided to
3552 forbid it. Similarly unclear is what should be generated when the
3553 C<\N{...}> is used as one of the end points of the range, such as in
3555 [\x{41}-\N{ARABIC SEQUENCE YEH WITH HAMZA ABOVE WITH AE}]
3557 What is meant here is unclear, as the C<\N{...}> escape is a sequence
3558 of code points, so this is made an error.
3560 =item \N{NAME} must be resolved by the lexer in regex; marked by
3561 S<<-- HERE> in m/%s/
3563 (F) When compiling a regex pattern, an unresolved named character or
3564 sequence was encountered. This can happen in any of several ways that
3565 bypass the lexer, such as using single-quotish context, or an extra
3566 backslash in double-quotish:
3568 $re = '\N{SPACE}'; # Wrong!
3569 $re = "\\N{SPACE}"; # Wrong!
3572 Instead, use double-quotes with a single backslash:
3574 $re = "\N{SPACE}"; # ok
3577 The lexer can be bypassed as well by creating the pattern from smaller
3581 /${re}{SPACE}/; # Wrong!
3583 It's not a good idea to split a construct in the middle like this, and
3584 it doesn't work here. Instead use the solution above.
3586 Finally, the message also can happen under the C</x> regex modifier when the
3587 C<\N> is separated by spaces from the C<{>, in which case, remove the spaces.
3589 /\N {SPACE}/x; # Wrong!
3592 =item No %s allowed while running setuid
3594 (F) Certain operations are deemed to be too insecure for a setuid or
3595 setgid script to even be allowed to attempt. Generally speaking there
3596 will be another way to do what you want that is, if not secure, at least
3597 securable. See L<perlsec>.
3599 =item NO-BREAK SPACE in a charnames alias definition is deprecated
3601 (D deprecated) You defined a character name which contained a no-break
3602 space character. Change it to a regular space. Usually these names are
3603 defined in the C<:alias> import argument to C<use charnames>, but they
3604 could be defined by a translator installed into C<$^H{charnames}>. See
3605 L<charnames/CUSTOM ALIASES>.
3607 =item No code specified for -%c
3609 (F) Perl's B<-e> and B<-E> command-line options require an argument. If
3610 you want to run an empty program, pass the empty string as a separate
3611 argument or run a program consisting of a single 0 or 1:
3617 =item No comma allowed after %s
3619 (F) A list operator that has a filehandle or "indirect object" is
3620 not allowed to have a comma between that and the following arguments.
3621 Otherwise it'd be just another one of the arguments.
3623 One possible cause for this is that you expected to have imported
3624 a constant to your name space with B<use> or B<import> while no such
3625 importing took place, it may for example be that your operating
3626 system does not support that particular constant. Hopefully you did
3627 use an explicit import list for the constants you expect to see;
3628 please see L<perlfunc/use> and L<perlfunc/import>. While an
3629 explicit import list would probably have caught this error earlier
3630 it naturally does not remedy the fact that your operating system
3631 still does not support that constant. Maybe you have a typo in
3632 the constants of the symbol import list of B<use> or B<import> or in the
3633 constant name at the line where this error was triggered?
3635 =item No command into which to pipe on command line
3637 (F) An error peculiar to VMS. Perl handles its own command line
3638 redirection, and found a '|' at the end of the command line, so it
3639 doesn't know where you want to pipe the output from this command.
3641 =item No DB::DB routine defined
3643 (F) The currently executing code was compiled with the B<-d> switch, but
3644 for some reason the current debugger (e.g. F<perl5db.pl> or a C<Devel::>
3645 module) didn't define a routine to be called at the beginning of each
3648 =item No dbm on this machine
3650 (P) This is counted as an internal error, because every machine should
3651 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
3653 =item No DB::sub routine defined
3655 (F) The currently executing code was compiled with the B<-d> switch, but
3656 for some reason the current debugger (e.g. F<perl5db.pl> or a C<Devel::>
3657 module) didn't define a C<DB::sub> routine to be called at the beginning
3658 of each ordinary subroutine call.
3660 =item No directory specified for -I
3662 (F) The B<-I> command-line switch requires a directory name as part of the
3663 I<same> argument. Use B<-Ilib>, for instance. B<-I lib> won't work.
3665 =item No error file after 2> or 2>> on command line
3667 (F) An error peculiar to VMS. Perl handles its own command line
3668 redirection, and found a '2>' or a '2>>' on the command line, but can't
3669 find the name of the file to which to write data destined for stderr.
3671 =item No group ending character '%c' found in template
3673 (F) A pack or unpack template has an opening '(' or '[' without its
3674 matching counterpart. See L<perlfunc/pack>.
3676 =item No input file after < on command line
3678 (F) An error peculiar to VMS. Perl handles its own command line
3679 redirection, and found a '<' on the command line, but can't find the
3680 name of the file from which to read data for stdin.
3682 =item No next::method '%s' found for %s
3684 (F) C<next::method> found no further instances of this method name
3685 in the remaining packages of the MRO of this class. If you don't want
3686 it throwing an exception, use C<maybe::next::method>
3687 or C<next::can>. See L<mro>.
3689 =item Non-hex character in regex; marked by S<<-- HERE> in m/%s/
3691 (F) In a regular expression, there was a non-hexadecimal character where
3692 a hex one was expected, like
3697 =item Non-octal character in regex; marked by S<<-- HERE> in m/%s/
3699 (F) In a regular expression, there was a non-octal character where
3700 an octal one was expected, like
3704 =item Non-octal character '%c'. Resolved as "%s"
3706 (W digit) In parsing an octal numeric constant, a character was
3707 unexpectedly encountered that isn't octal. The resulting value
3710 =item "no" not allowed in expression
3712 (F) The "no" keyword is recognized and executed at compile time, and
3713 returns no useful value. See L<perlmod>.
3715 =item Non-string passed as bitmask
3717 (W misc) A number has been passed as a bitmask argument to select().
3718 Use the vec() function to construct the file descriptor bitmasks for
3719 select. See L<perlfunc/select>.
3721 =item No output file after > on command line
3723 (F) An error peculiar to VMS. Perl handles its own command line
3724 redirection, and found a lone '>' at the end of the command line, so it
3725 doesn't know where you wanted to redirect stdout.
3727 =item No output file after > or >> on command line
3729 (F) An error peculiar to VMS. Perl handles its own command line
3730 redirection, and found a '>' or a '>>' on the command line, but can't
3731 find the name of the file to which to write data destined for stdout.
3733 =item No package name allowed for variable %s in "our"
3735 (F) Fully qualified variable names are not allowed in "our"
3736 declarations, because that doesn't make much sense under existing
3737 semantics. Such syntax is reserved for future extensions.
3739 =item No Perl script found in input
3741 (F) You called C<perl -x>, but no line was found in the file beginning
3742 with #! and containing the word "perl".
3744 =item No setregid available
3746 (F) Configure didn't find anything resembling the setregid() call for
3749 =item No setreuid available
3751 (F) Configure didn't find anything resembling the setreuid() call for
3754 =item No such class %s
3756 (F) You provided a class qualifier in a "my", "our" or "state"
3757 declaration, but this class doesn't exist at this point in your program.
3759 =item No such class field "%s" in variable %s of type %s
3761 (F) You tried to access a key from a hash through the indicated typed
3762 variable but that key is not allowed by the package of the same type.
3763 The indicated package has restricted the set of allowed keys using the
3766 =item No such hook: %s
3768 (F) You specified a signal hook that was not recognized by Perl.
3769 Currently, Perl accepts C<__DIE__> and C<__WARN__> as valid signal hooks.
3771 =item No such pipe open
3773 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
3774 close a pipe which hadn't been opened. This should have been caught
3775 earlier as an attempt to close an unopened filehandle.
3777 =item No such signal: SIG%s
3779 (W signal) You specified a signal name as a subscript to %SIG that was
3780 not recognized. Say C<kill -l> in your shell to see the valid signal
3781 names on your system.
3783 =item Not a CODE reference
3785 (F) Perl was trying to evaluate a reference to a code value (that is, a
3786 subroutine), but found a reference to something else instead. You can
3787 use the ref() function to find out what kind of ref it really was. See
3790 =item Not a GLOB reference
3792 (F) Perl was trying to evaluate a reference to a "typeglob" (that is, a
3793 symbol table entry that looks like C<*foo>), but found a reference to
3794 something else instead. You can use the ref() function to find out what
3795 kind of ref it really was. See L<perlref>.
3797 =item Not a HASH reference
3799 (F) Perl was trying to evaluate a reference to a hash value, but found a
3800 reference to something else instead. You can use the ref() function to
3801 find out what kind of ref it really was. See L<perlref>.
3803 =item Not an ARRAY reference
3805 (F) Perl was trying to evaluate a reference to an array value, but found
3806 a reference to something else instead. You can use the ref() function
3807 to find out what kind of ref it really was. See L<perlref>.
3809 =item Not an unblessed ARRAY reference
3811 (F) You passed a reference to a blessed array to C<push>, C<shift> or
3812 another array function. These only accept unblessed array references
3813 or arrays beginning explicitly with C<@>.
3815 =item Not a SCALAR reference
3817 (F) Perl was trying to evaluate a reference to a scalar value, but found
3818 a reference to something else instead. You can use the ref() function
3819 to find out what kind of ref it really was. See L<perlref>.
3821 =item Not a subroutine reference
3823 (F) Perl was trying to evaluate a reference to a code value (that is, a
3824 subroutine), but found a reference to something else instead. You can
3825 use the ref() function to find out what kind of ref it really was. See
3828 =item Not a subroutine reference in overload table
3830 (F) An attempt was made to specify an entry in an overloading table that
3831 doesn't somehow point to a valid subroutine. See L<overload>.
3833 =item Not enough arguments for %s
3835 (F) The function requires more arguments than you specified.
3837 =item Not enough format arguments
3839 (W syntax) A format specified more picture fields than the next line
3840 supplied. See L<perlform>.
3844 (A) You've accidentally run your script through the Bourne shell instead
3845 of Perl. Check the #! line, or manually feed your script into Perl
3848 =item (?[...]) not valid in locale in regex; marked by S<<-- HERE> in m/%s/
3850 (F) C<(?[...])> cannot be used within the scope of a C<S<use locale>> or with
3851 an C</l> regular expression modifier, as that would require deferring
3852 to run-time the calculation of what it should evaluate to, and it is
3853 regex compile-time only.
3855 =item no UTC offset information; assuming local time is UTC
3857 (S) A warning peculiar to VMS. Perl was unable to find the local
3858 timezone offset, so it's assuming that local system time is equivalent
3859 to UTC. If it's not, define the logical name
3860 F<SYS$TIMEZONE_DIFFERENTIAL> to translate to the number of seconds which
3861 need to be added to UTC to get local time.
3863 =item NULL OP IN RUN
3865 (S debugging) Some internal routine called run() with a null opcode
3868 =item Null picture in formline
3870 (F) The first argument to formline must be a valid format picture
3871 specification. It was found to be empty, which probably means you
3872 supplied it an uninitialized value. See L<perlform>.
3876 (P) An attempt was made to realloc NULL.
3878 =item NULL regexp argument
3880 (P) The internal pattern matching routines blew it big time.
3882 =item NULL regexp parameter
3884 (P) The internal pattern matching routines are out of their gourd.
3886 =item Number too long
3888 (F) Perl limits the representation of decimal numbers in programs to
3889 about 250 characters. You've exceeded that length. Future
3890 versions of Perl are likely to eliminate this arbitrary limitation. In
3891 the meantime, try using scientific notation (e.g. "1e6" instead of
3894 =item Number with no digits
3896 (F) Perl was looking for a number but found nothing that looked like
3897 a number. This happens, for example with C<\o{}>, with no number between
3900 =item Octal number > 037777777777 non-portable
3902 (W portable) The octal number you specified is larger than 2**32-1
3903 (4294967295) and therefore non-portable between systems. See
3904 L<perlport> for more on portability concerns.
3906 =item Odd name/value argument for subroutine
3908 (F) A subroutine using a slurpy hash parameter in its signature
3909 received an odd number of arguments to populate the hash. It requires
3910 the arguments to be paired, with the same number of keys as values.
3911 The caller of the subroutine is presumably at fault. Inconveniently,
3912 this error will be reported at the location of the subroutine, not that
3915 =item Odd number of arguments for overload::constant
3917 (W overload) The call to overload::constant contained an odd number of
3918 arguments. The arguments should come in pairs.
3920 =item Odd number of elements in anonymous hash
3922 (W misc) You specified an odd number of elements to initialize a hash,
3923 which is odd, because hashes come in key/value pairs.
3925 =item Odd number of elements in hash assignment
3927 (W misc) You specified an odd number of elements to initialize a hash,
3928 which is odd, because hashes come in key/value pairs.
3930 =item Offset outside string
3932 (F)(W layer) You tried to do a read/write/send/recv/seek operation
3933 with an offset pointing outside the buffer. This is difficult to
3934 imagine. The sole exceptions to this are that zero padding will
3935 take place when going past the end of the string when either
3936 C<sysread()>ing a file, or when seeking past the end of a scalar opened
3937 for I/O (in anticipation of future reads and to imitate the behavior
3940 =item %s() on unopened %s
3942 (W unopened) An I/O operation was attempted on a filehandle that was
3943 never initialized. You need to do an open(), a sysopen(), or a socket()
3944 call, or call a constructor from the FileHandle package.
3946 =item -%s on unopened filehandle %s
3948 (W unopened) You tried to invoke a file test operator on a filehandle
3949 that isn't open. Check your control flow. See also L<perlfunc/-X>.
3953 (S internal) An internal warning that the grammar is screwed up.
3957 (S internal) An internal warning that the grammar is screwed up.
3959 =item Opening dirhandle %s also as a file
3961 (D io, deprecated) You used open() to associate a filehandle to
3962 a symbol (glob or scalar) that already holds a dirhandle.
3963 Although legal, this idiom might render your code confusing
3966 =item Opening filehandle %s also as a directory
3968 (D io, deprecated) You used opendir() to associate a dirhandle to
3969 a symbol (glob or scalar) that already holds a filehandle.
3970 Although legal, this idiom might render your code confusing
3973 =item Operand with no preceding operator in regex; marked by S<<-- HERE> in
3976 (F) You wrote something like
3978 (?[ \p{Digit} \p{Thai} ])
3980 There are two operands, but no operator giving how you want to combine
3983 =item Operation "%s": no method found, %s
3985 (F) An attempt was made to perform an overloaded operation for which no
3986 handler was defined. While some handlers can be autogenerated in terms
3987 of other handlers, there is no default handler for any operation, unless
3988 the C<fallback> overloading key is specified to be true. See L<overload>.
3990 =item Operation "%s" returns its argument for non-Unicode code point 0x%X
3992 (S non_unicode) You performed an operation requiring Unicode semantics
3993 on a code point that is not in Unicode, so what it should do is not
3994 defined. Perl has chosen to have it do nothing, and warn you.
3996 If the operation shown is "ToFold", it means that case-insensitive
3997 matching in a regular expression was done on the code point.
3999 If you know what you are doing you can turn off this warning by
4000 C<no warnings 'non_unicode';>.
4002 =item Operation "%s" returns its argument for UTF-16 surrogate U+%X
4004 (S surrogate) You performed an operation requiring Unicode
4005 semantics on a Unicode surrogate. Unicode frowns upon the use
4006 of surrogates for anything but storing strings in UTF-16, but
4007 semantics are (reluctantly) defined for the surrogates, and
4008 they are to do nothing for this operation. Because the use of
4009 surrogates can be dangerous, Perl warns.
4011 If the operation shown is "ToFold", it means that case-insensitive
4012 matching in a regular expression was done on the code point.
4014 If you know what you are doing you can turn off this warning by
4015 C<no warnings 'surrogate';>.
4017 =item Operator or semicolon missing before %s
4019 (S ambiguous) You used a variable or subroutine call where the parser
4020 was expecting an operator. The parser has assumed you really meant to
4021 use an operator, but this is highly likely to be incorrect. For
4022 example, if you say "*foo *foo" it will be interpreted as if you said
4025 =item Optional parameter lacks default expression
4027 (F) In a subroutine signature, you wrote something like "$a =", making a
4028 named optional parameter without a default value. A nameless optional
4029 parameter is permitted to have no default value, but a named one must
4030 have a specific default. You probably want "$a = undef".
4032 =item "our" variable %s redeclared
4034 (W misc) You seem to have already declared the same global once before
4035 in the current lexical scope.
4037 =item Out of memory!
4039 (X) The malloc() function returned 0, indicating there was insufficient
4040 remaining memory (or virtual memory) to satisfy the request. Perl has
4041 no option but to exit immediately.
4043 At least in Unix you may be able to get past this by increasing your
4044 process datasize limits: in csh/tcsh use C<limit> and
4045 C<limit datasize n> (where C<n> is the number of kilobytes) to check
4046 the current limits and change them, and in ksh/bash/zsh use C<ulimit -a>
4047 and C<ulimit -d n>, respectively.
4049 =item Out of memory during %s extend
4051 (X) An attempt was made to extend an array, a list, or a string beyond
4052 the largest possible memory allocation.
4054 =item Out of memory during "large" request for %s
4056 (F) The malloc() function returned 0, indicating there was insufficient
4057 remaining memory (or virtual memory) to satisfy the request. However,
4058 the request was judged large enough (compile-time default is 64K), so a
4059 possibility to shut down by trapping this error is granted.
4061 =item Out of memory during request for %s
4063 (X)(F) The malloc() function returned 0, indicating there was
4064 insufficient remaining memory (or virtual memory) to satisfy the
4067 The request was judged to be small, so the possibility to trap it
4068 depends on the way perl was compiled. By default it is not trappable.
4069 However, if compiled for this, Perl may use the contents of C<$^M> as an
4070 emergency pool after die()ing with this message. In this case the error
4071 is trappable I<once>, and the error message will include the line and file
4072 where the failed request happened.
4074 =item Out of memory during ridiculously large request
4076 (F) You can't allocate more than 2^31+"small amount" bytes. This error
4077 is most likely to be caused by a typo in the Perl program. e.g.,
4078 C<$arr[time]> instead of C<$arr[$time]>.
4080 =item Out of memory for yacc stack
4082 (F) The yacc parser wanted to grow its stack so it could continue
4083 parsing, but realloc() wouldn't give it more memory, virtual or
4086 =item '.' outside of string in pack
4088 (F) The argument to a '.' in your template tried to move the working
4089 position to before the start of the packed string being built.
4091 =item '@' outside of string in unpack
4093 (F) You had a template that specified an absolute position outside
4094 the string being unpacked. See L<perlfunc/pack>.
4096 =item '@' outside of string with malformed UTF-8 in unpack
4098 (F) You had a template that specified an absolute position outside
4099 the string being unpacked. The string being unpacked was also invalid
4100 UTF-8. See L<perlfunc/pack>.
4102 =item overload arg '%s' is invalid
4104 (W overload) The L<overload> pragma was passed an argument it did not
4105 recognize. Did you mistype an operator?
4107 =item Overloaded dereference did not return a reference
4109 (F) An object with an overloaded dereference operator was dereferenced,
4110 but the overloaded operation did not return a reference. See
4113 =item Overloaded qr did not return a REGEXP
4115 (F) An object with a C<qr> overload was used as part of a match, but the
4116 overloaded operation didn't return a compiled regexp. See L<overload>.
4118 =item %s package attribute may clash with future reserved word: %s
4120 (W reserved) A lowercase attribute name was used that had a
4121 package-specific handler. That name might have a meaning to Perl itself
4122 some day, even though it doesn't yet. Perhaps you should use a
4123 mixed-case attribute name, instead. See L<attributes>.
4125 =item pack/unpack repeat count overflow
4127 (F) You can't specify a repeat count so large that it overflows your
4128 signed integers. See L<perlfunc/pack>.
4132 (W io) A single call to write() produced more lines than can fit on a
4133 page. See L<perlform>.
4137 (P) An internal error.
4139 =item panic: attempt to call %s in %s
4141 (P) One of the file test operators entered a code branch that calls
4142 an ACL related-function, but that function is not available on this
4143 platform. Earlier checks mean that it should not be possible to
4144 enter this branch on this platform.
4146 =item panic: child pseudo-process was never scheduled
4148 (P) A child pseudo-process in the ithreads implementation on Windows
4149 was not scheduled within the time period allowed and therefore was not
4150 able to initialize properly.
4152 =item panic: ck_grep, type=%u
4154 (P) Failed an internal consistency check trying to compile a grep.
4156 =item panic: ck_split, type=%u
4158 (P) Failed an internal consistency check trying to compile a split.
4160 =item panic: corrupt saved stack index %ld
4162 (P) The savestack was requested to restore more localized values than
4163 there are in the savestack.
4165 =item panic: del_backref
4167 (P) Failed an internal consistency check while trying to reset a weak
4172 (P) We popped the context stack to an eval context, and then discovered
4173 it wasn't an eval context.
4175 =item panic: do_subst
4177 (P) The internal pp_subst() routine was called with invalid operational
4180 =item panic: do_trans_%s
4182 (P) The internal do_trans routines were called with invalid operational
4185 =item panic: fold_constants JMPENV_PUSH returned %d
4187 (P) While attempting folding constants an exception other than an C<eval>
4190 =item panic: frexp: %f
4192 (P) The library function frexp() failed, making printf("%f") impossible.
4194 =item panic: goto, type=%u, ix=%ld
4196 (P) We popped the context stack to a context with the specified label,
4197 and then discovered it wasn't a context we know how to do a goto in.
4199 =item panic: gp_free failed to free glob pointer
4201 (P) The internal routine used to clear a typeglob's entries tried
4202 repeatedly, but each time something re-created entries in the glob.
4203 Most likely the glob contains an object with a reference back to
4204 the glob and a destructor that adds a new object to the glob.
4206 =item panic: INTERPCASEMOD, %s
4208 (P) The lexer got into a bad state at a case modifier.
4210 =item panic: INTERPCONCAT, %s
4212 (P) The lexer got into a bad state parsing a string with brackets.
4214 =item panic: kid popen errno read
4216 (F) A forked child returned an incomprehensible message about its errno.
4218 =item panic: last, type=%u
4220 (P) We popped the context stack to a block context, and then discovered
4221 it wasn't a block context.
4223 =item panic: leave_scope clearsv
4225 (P) A writable lexical variable became read-only somehow within the
4228 =item panic: leave_scope inconsistency %u
4230 (P) The savestack probably got out of sync. At least, there was an
4231 invalid enum on the top of it.
4233 =item panic: magic_killbackrefs
4235 (P) Failed an internal consistency check while trying to reset all weak
4236 references to an object.
4238 =item panic: malloc, %s
4240 (P) Something requested a negative number of bytes of malloc.
4242 =item panic: memory wrap
4244 (P) Something tried to allocate either more memory than possible or a
4247 =item panic: pad_alloc, %p!=%p
4249 (P) The compiler got confused about which scratch pad it was allocating
4250 and freeing temporaries and lexicals from.
4252 =item panic: pad_free curpad, %p!=%p
4254 (P) The compiler got confused about which scratch pad it was allocating
4255 and freeing temporaries and lexicals from.
4257 =item panic: pad_free po
4259 (P) A zero scratch pad offset was detected internally. An attempt was
4260 made to free a target that had not been allocated to begin with.
4262 =item panic: pad_reset curpad, %p!=%p
4264 (P) The compiler got confused about which scratch pad it was allocating
4265 and freeing temporaries and lexicals from.
4267 =item panic: pad_sv po
4269 (P) A zero scratch pad offset was detected internally. Most likely
4270 an operator needed a target but that target had not been allocated
4271 for whatever reason.
4273 =item panic: pad_swipe curpad, %p!=%p
4275 (P) The compiler got confused about which scratch pad it was allocating
4276 and freeing temporaries and lexicals from.
4278 =item panic: pad_swipe po
4280 (P) An invalid scratch pad offset was detected internally.
4282 =item panic: pp_iter, type=%u
4284 (P) The foreach iterator got called in a non-loop context frame.
4286 =item panic: pp_match%s
4288 (P) The internal pp_match() routine was called with invalid operational
4291 =item panic: pp_split, pm=%p, s=%p
4293 (P) Something terrible went wrong in setting up for the split.
4295 =item panic: realloc, %s
4297 (P) Something requested a negative number of bytes of realloc.
4299 =item panic: reference miscount on nsv in sv_replace() (%d != 1)
4301 (P) The internal sv_replace() function was handed a new SV with a
4302 reference count other than 1.
4304 =item panic: restartop in %s
4306 (P) Some internal routine requested a goto (or something like it), and
4307 didn't supply the destination.
4309 =item panic: return, type=%u
4311 (P) We popped the context stack to a subroutine or eval context, and
4312 then discovered it wasn't a subroutine or eval context.
4314 =item panic: scan_num, %s
4316 (P) scan_num() got called on something that wasn't a number.
4318 =item panic: Sequence (?{...}): no code block found in regex m/%s/
4320 (P) While compiling a pattern that has embedded (?{}) or (??{}) code
4321 blocks, perl couldn't locate the code block that should have already been
4322 seen and compiled by perl before control passed to the regex compiler.
4324 =item panic: strxfrm() gets absurd - a => %u, ab => %u
4326 (P) The interpreter's sanity check of the C function strxfrm() failed.
4327 In your current locale the returned transformation of the string "ab"
4328 is shorter than that of the string "a", which makes no sense.
4330 =item panic: sv_chop %s
4332 (P) The sv_chop() routine was passed a position that is not within the
4333 scalar's string buffer.
4335 =item panic: sv_insert, midend=%p, bigend=%p
4337 (P) The sv_insert() routine was told to remove more string than there
4340 =item panic: top_env
4342 (P) The compiler attempted to do a goto, or something weird like that.
4344 =item panic: unimplemented op %s (#%d) called
4346 (P) The compiler is screwed up and attempted to use an op that isn't
4347 permitted at run time.
4349 =item panic: utf16_to_utf8: odd bytelen
4351 (P) Something tried to call utf16_to_utf8 with an odd (as opposed
4352 to even) byte length.
4354 =item panic: utf16_to_utf8_reversed: odd bytelen
4356 (P) Something tried to call utf16_to_utf8_reversed with an odd (as opposed
4357 to even) byte length.
4359 =item panic: yylex, %s
4361 (P) The lexer got into a bad state while processing a case modifier.
4363 =item Parentheses missing around "%s" list
4365 (W parenthesis) You said something like
4371 my ($foo, $bar) = @_;
4373 Remember that "my", "our", "local" and "state" bind tighter than comma.
4375 =item Parsing code internal error (%s)
4377 (F) Parsing code supplied by an extension violated the parser's API in
4380 =item Passing malformed UTF-8 to "%s" is deprecated
4382 (D deprecated, utf8) This message indicates a bug either in the Perl
4383 core or in XS code. Such code was trying to find out if a character,
4384 allegedly stored internally encoded as UTF-8, was of a given type, such
4385 as being punctuation or a digit. But the character was not encoded in
4386 legal UTF-8. The C<%s> is replaced by a string that can be used by
4387 knowledgeable people to determine what the type being checked against
4388 was. If C<utf8> warnings are enabled, a further message is raised,
4389 giving details of the malformation.
4391 =item Pattern subroutine nesting without pos change exceeded limit in regex
4393 (F) You used a pattern that uses too many nested subpattern calls without
4394 consuming any text. Restructure the pattern so text is consumed before
4395 the nesting limit is exceeded.
4397 =item C<-p> destination: %s
4399 (F) An error occurred during the implicit output invoked by the C<-p>
4400 command-line switch. (This output goes to STDOUT unless you've
4401 redirected it with select().)
4403 =item Perl API version %s of %s does not match %s
4405 (F) The XS module in question was compiled against a different incompatible
4406 version of Perl than the one that has loaded the XS module.
4408 =item Perl folding rules are not up-to-date for 0x%X; please use the perlbug
4409 utility to report; in regex; marked by S<<-- HERE> in m/%s/
4411 (S regexp) You used a regular expression with case-insensitive matching,
4412 and there is a bug in Perl in which the built-in regular expression
4413 folding rules are not accurate. This may lead to incorrect results.
4414 Please report this as a bug using the L<perlbug> utility.
4416 =item PerlIO layer ':win32' is experimental
4418 (S experimental::win32_perlio) The C<:win32> PerlIO layer is
4419 experimental. If you want to take the risk of using this layer,
4420 simply disable this warning:
4422 no warnings "experimental::win32_perlio";
4424 =item Perl_my_%s() not available
4426 (F) Your platform has very uncommon byte-order and integer size,
4427 so it was not possible to set up some or all fixed-width byte-order
4428 conversion functions. This is only a problem when you're using the
4429 '<' or '>' modifiers in (un)pack templates. See L<perlfunc/pack>.
4431 =item Perl %s required (did you mean %s?)--this is only %s, stopped
4433 (F) The code you are trying to run has asked for a newer version of
4434 Perl than you are running. Perhaps C<use 5.10> was written instead
4435 of C<use 5.010> or C<use v5.10>. Without the leading C<v>, the number is
4436 interpreted as a decimal, with every three digits after the
4437 decimal point representing a part of the version number. So 5.10
4438 is equivalent to v5.100.
4440 =item Perl %s required--this is only %s, stopped
4442 (F) The module in question uses features of a version of Perl more
4443 recent than the currently running version. How long has it been since
4444 you upgraded, anyway? See L<perlfunc/require>.
4446 =item PERL_SH_DIR too long
4448 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
4449 C<sh>-shell in. See "PERL_SH_DIR" in L<perlos2>.
4451 =item PERL_SIGNALS illegal: "%s"
4453 (X) See L<perlrun/PERL_SIGNALS> for legal values.
4455 =item Perls since %s too modern--this is %s, stopped
4457 (F) The code you are trying to run claims it will not run
4458 on the version of Perl you are using because it is too new.
4459 Maybe the code needs to be updated, or maybe it is simply
4460 wrong and the version check should just be removed.
4462 =item perl: warning: Non hex character in '$ENV{PERL_HASH_SEED}', seed only partially set
4464 (S) PERL_HASH_SEED should match /^\s*(?:0x)?[0-9a-fA-F]+\s*\z/ but it
4465 contained a non hex character. This could mean you are not using the
4466 hash seed you think you are.
4468 =item perl: warning: Setting locale failed.
4470 (S) The whole warning message will look something like:
4472 perl: warning: Setting locale failed.
4473 perl: warning: Please check that your locale settings:
4476 are supported and installed on your system.
4477 perl: warning: Falling back to the standard locale ("C").
4479 Exactly what were the failed locale settings varies. In the above the
4480 settings were that the LC_ALL was "En_US" and the LANG had no value.
4481 This error means that Perl detected that you and/or your operating
4482 system supplier and/or system administrator have set up the so-called
4483 locale system but Perl could not use those settings. This was not
4484 dead serious, fortunately: there is a "default locale" called "C" that
4485 Perl can and will use, and the script will be run. Before you really
4486 fix the problem, however, you will get the same error message each
4487 time you run Perl. How to really fix the problem can be found in
4488 L<perllocale> section B<LOCALE PROBLEMS>.
4490 =item perl: warning: strange setting in '$ENV{PERL_PERTURB_KEYS}': '%s'
4492 (S) Perl was run with the environment variable PERL_PERTURB_KEYS defined
4493 but containing an unexpected value. The legal values of this setting
4496 Numeric | String | Result
4497 --------+---------------+-----------------------------------------
4498 0 | NO | Disables key traversal randomization
4499 1 | RANDOM | Enables full key traversal randomization
4500 2 | DETERMINISTIC | Enables repeatable key traversal
4503 Both numeric and string values are accepted, but note that string values are
4504 case sensitive. The default for this setting is "RANDOM" or 1.
4506 =item pid %x not a child
4508 (W exec) A warning peculiar to VMS. Waitpid() was asked to wait for a
4509 process which isn't a subprocess of the current process. While this is
4510 fine from VMS' perspective, it's probably not what you intended.
4512 =item 'P' must have an explicit size in unpack
4514 (F) The unpack format P must have an explicit size, not "*".
4516 =item pop on reference is experimental
4518 (S experimental::autoderef) C<pop> with a scalar argument is experimental
4519 and may change or be removed in a future Perl version. If you want to
4520 take the risk of using this feature, simply disable this warning:
4522 no warnings "experimental::autoderef";
4524 =item POSIX class [:%s:] unknown in regex; marked by S<< <-- HERE in m/%s/ >>
4526 (F) The class in the character class [: :] syntax is unknown. The S<<-- HERE>
4527 shows whereabouts in the regular expression the problem was discovered.
4528 Note that the POSIX character classes do B<not> have the C<is> prefix
4529 the corresponding C interfaces have: in other words, it's C<[[:print:]]>,
4530 not C<isprint>. See L<perlre>.
4532 =item POSIX getpgrp can't take an argument
4534 (F) Your system has POSIX getpgrp(), which takes no argument, unlike
4535 the BSD version, which takes a pid.
4537 =item POSIX syntax [%c %c] belongs inside character classes in regex; marked by
4538 S<<-- HERE> in m/%s/
4540 (W regexp) The character class constructs [: :], [= =], and [. .] go
4541 I<inside> character classes, the [] are part of the construct, for example:
4542 /[012[:alpha:]345]/. Note that [= =] and [. .] are not currently
4543 implemented; they are simply placeholders for future extensions and
4544 will cause fatal errors. The S<<-- HERE> shows whereabouts in the regular
4545 expression the problem was discovered. See L<perlre>.
4547 =item POSIX syntax [. .] is reserved for future extensions in regex; marked by
4548 S<<-- HERE> in m/%s/
4550 (F) Within regular expression character classes ([]) the syntax beginning
4551 with "[." and ending with ".]" is reserved for future extensions. If you
4552 need to represent those character sequences inside a regular expression
4553 character class, just quote the square brackets with the backslash: "\[."
4554 and ".\]". The S<<-- HERE> shows whereabouts in the regular expression the
4555 problem was discovered. See L<perlre>.
4557 =item POSIX syntax [= =] is reserved for future extensions in regex; marked by
4558 S<<-- HERE> in m/%s/
4560 (F) Within regular expression character classes ([]) the syntax beginning
4561 with "[=" and ending with "=]" is reserved for future extensions. If you
4562 need to represent those character sequences inside a regular expression
4563 character class, just quote the square brackets with the backslash: "\[="
4564 and "=\]". The S<<-- HERE> shows whereabouts in the regular expression the
4565 problem was discovered. See L<perlre>.
4567 =item Possible attempt to put comments in qw() list
4569 (W qw) qw() lists contain items separated by whitespace; as with literal
4570 strings, comment characters are not ignored, but are instead treated as
4571 literal data. (You may have used different delimiters than the
4572 parentheses shown here; braces are also frequently used.)
4574 You probably wrote something like this:
4581 when you should have written this:
4588 If you really want comments, build your list the
4589 old-fashioned way, with quotes and commas:
4593 'b', # another comment
4596 =item Possible attempt to separate words with commas
4598 (W qw) qw() lists contain items separated by whitespace; therefore
4599 commas aren't needed to separate the items. (You may have used
4600 different delimiters than the parentheses shown here; braces are also
4603 You probably wrote something like this:
4607 which puts literal commas into some of the list items. Write it without
4608 commas if you don't want them to appear in your data:
4612 =item Possible memory corruption: %s overflowed 3rd argument
4614 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
4615 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
4616 end of the buffer just in case. This sentinel byte got clobbered, and
4617 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
4619 =item Possible precedence issue with control flow operator
4621 (W syntax) There is a possible problem with the mixing of a control
4622 flow operator (e.g. C<return>) and a low-precedence operator like
4625 sub { return $a or $b; }
4629 sub { (return $a) or $b; }
4631 Which is effectively just:
4635 Either use parentheses or the high-precedence variant of the operator.
4637 Note this may be also triggered for constructs like:
4641 =item Possible precedence problem on bitwise %c operator
4643 (W precedence) Your program uses a bitwise logical operator in conjunction
4644 with a numeric comparison operator, like this :
4646 if ($x & $y == 0) { ... }
4648 This expression is actually equivalent to C<$x & ($y == 0)>, due to the
4649 higher precedence of C<==>. This is probably not what you want. (If you
4650 really meant to write this, disable the warning, or, better, put the
4651 parentheses explicitly and write C<$x & ($y == 0)>).
4653 =item Possible unintended interpolation of $\ in regex
4655 (W ambiguous) You said something like C<m/$\/> in a regex.
4656 The regex C<m/foo$\s+bar/m> translates to: match the word 'foo', the output
4657 record separator (see L<perlvar/$\>) and the letter 's' (one time or more)
4658 followed by the word 'bar'.
4660 If this is what you intended then you can silence the warning by using
4661 C<m/${\}/> (for example: C<m/foo${\}s+bar/>).
4663 If instead you intended to match the word 'foo' at the end of the line
4664 followed by whitespace and the word 'bar' on the next line then you can use
4665 C<m/$(?)\/> (for example: C<m/foo$(?)\s+bar/>).
4667 =item Possible unintended interpolation of %s in string
4669 (W ambiguous) You said something like '@foo' in a double-quoted string
4670 but there was no array C<@foo> in scope at the time. If you wanted a
4671 literal @foo, then write it as \@foo; otherwise find out what happened
4672 to the array you apparently lost track of.
4674 =item Postfix dereference is experimental
4676 (S experimental::postderef) This warning is emitted if you use
4677 the experimental postfix dereference syntax. Simply suppress the
4678 warning if you want to use the feature, but know that in doing
4679 so you are taking the risk of using an experimental feature which
4680 may change or be removed in a future Perl version:
4682 no warnings "experimental::postderef";
4683 use feature "postderef", "postderef_qq";
4689 =item Precedence problem: open %s should be open(%s)
4691 (S precedence) The old irregular construct
4695 is now misinterpreted as
4699 because of the strict regularization of Perl 5's grammar into unary and
4700 list operators. (The old open was a little of both.) You must put
4701 parentheses around the filehandle, or use the new "or" operator instead
4704 =item Premature end of script headers
4708 =item printf() on closed filehandle %s
4710 (W closed) The filehandle you're writing to got itself closed sometime
4711 before now. Check your control flow.
4713 =item print() on closed filehandle %s
4715 (W closed) The filehandle you're printing on got itself closed sometime
4716 before now. Check your control flow.
4718 =item Process terminated by SIG%s
4720 (W) This is a standard message issued by OS/2 applications, while *nix
4721 applications die in silence. It is considered a feature of the OS/2
4722 port. One can easily disable this by appropriate sighandlers, see
4723 L<perlipc/"Signals">. See also "Process terminated by SIGTERM/SIGINT"
4726 =item Property '%s' is unknown in regex; marked by S<<-- HERE> in m/%s/
4728 (F) The named property which you specified via C<\p> or C<\P> is not one
4729 known to Perl. Perhaps you misspelled the name? See
4730 L<perluniprops/Properties accessible through \p{} and \P{}>
4731 for a complete list of available official
4732 properties. If it is a L<user-defined property|perlunicode/User-Defined Character Properties>
4733 it must have been defined by the time the regular expression is
4736 =item Prototype after '%c' for %s : %s
4738 (W illegalproto) A character follows % or @ in a prototype. This is
4739 useless, since % and @ gobble the rest of the subroutine arguments.
4741 =item Prototype mismatch: %s vs %s
4743 (S prototype) The subroutine being declared or defined had previously been
4744 declared or defined with a different function prototype.
4746 =item Prototype not terminated
4748 (F) You've omitted the closing parenthesis in a function prototype
4751 =item Prototype '%s' overridden by attribute 'prototype(%s)' in %s
4753 (W prototype) A prototype was declared in both the parentheses after
4754 the sub name and via the prototype attribute. The prototype in
4755 parentheses is useless, since it will be replaced by the prototype
4756 from the attribute before it's ever used.
4758 =item push on reference is experimental
4760 (S experimental::autoderef) C<push> with a scalar argument is experimental
4761 and may change or be removed in a future Perl version. If you want to
4762 take the risk of using this feature, simply disable this warning:
4764 no warnings "experimental::autoderef";
4766 =item Quantifier follows nothing in regex; marked by S<< <-- HERE in m/%s/ >>
4768 (F) You started a regular expression with a quantifier. Backslash it if
4769 you meant it literally. The S<<-- HERE> shows whereabouts in the regular
4770 expression the problem was discovered. See L<perlre>.
4772 =item Quantifier in {,} bigger than %d in regex; marked by S<<-- HERE> in
4775 (F) There is currently a limit to the size of the min and max values of
4776 the {min,max} construct. The S<<-- HERE> shows whereabouts in the regular
4777 expression the problem was discovered. See L<perlre>.
4779 =item Quantifier {n,m} with n > m can't match in regex
4781 =item Quantifier {n,m} with n > m can't match in regex; marked by
4782 S<<-- HERE> in m/%s/
4784 (W regexp) Minima should be less than or equal to maxima. If you really
4785 want your regexp to match something 0 times, just put {0}.
4787 =item Quantifier unexpected on zero-length expression in regex m/%s/
4789 (W regexp) You applied a regular expression quantifier in a place where
4790 it makes no sense, such as on a zero-width assertion. Try putting the
4791 quantifier inside the assertion instead. For example, the way to match
4792 "abc" provided that it is followed by three repetitions of "xyz" is
4793 C</abc(?=(?:xyz){3})/>, not C</abc(?=xyz){3}/>.
4795 =item Range iterator outside integer range
4797 (F) One (or both) of the numeric arguments to the range operator ".."
4798 are outside the range which can be represented by integers internally.
4799 One possible workaround is to force Perl to use magical string increment
4800 by prepending "0" to your numbers.
4802 =item readdir() attempted on invalid dirhandle %s
4804 (W io) The dirhandle you're reading from is either closed or not really
4805 a dirhandle. Check your control flow.
4807 =item readline() on closed filehandle %s
4809 (W closed) The filehandle you're reading from got itself closed sometime
4810 before now. Check your control flow.
4812 =item read() on closed filehandle %s
4814 (W closed) You tried to read from a closed filehandle.
4816 =item read() on unopened filehandle %s
4818 (W unopened) You tried to read from a filehandle that was never opened.
4820 =item Reallocation too large: %x
4822 (F) You can't allocate more than 64K on an MS-DOS machine.
4824 =item realloc() of freed memory ignored
4826 (S malloc) An internal routine called realloc() on something that had