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1=head1 NAME
2
3perldiag - various Perl diagnostics
4
5=head1 DESCRIPTION
6
7These messages are classified as follows (listed in increasing order of
8desperation):
9
10 (W) A warning (optional).
d1d15184 11 (D) A deprecation (enabled by default).
00eb3f2b 12 (S) A severe warning (enabled by default).
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13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
54310121 15 (X) A very fatal error (nontrappable).
cb1a09d0 16 (A) An alien error message (not generated by Perl).
a0d0e21e 17
75b44862 18The majority of messages from the first three classifications above
64977eb6 19(W, D & S) can be controlled using the C<warnings> pragma.
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20
21If a message can be controlled by the C<warnings> pragma, its warning
22category is included with the classification letter in the description
466416ed 23below. E.g. C<(W closed)> means a warning in the C<closed> category.
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24
25Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
fa816bf3 26and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
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27to a reference to a routine that will be called on each warning instead
28of printing it. See L<perlvar>.
29
b7eceb5b 30Severe warnings are always enabled, unless they are explicitly disabled
e476b1b5 31with the C<warnings> pragma or the B<-X> switch.
4438c4b7 32
748a9306 33Trappable errors may be trapped using the eval operator. See
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34L<perlfunc/eval>. In almost all cases, warnings may be selectively
35disabled or promoted to fatal errors using the C<warnings> pragma.
36See L<warnings>.
a0d0e21e 37
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38The messages are in alphabetical order, without regard to upper or
39lower-case. Some of these messages are generic. Spots that vary are
40denoted with a %s or other printf-style escape. These escapes are
41ignored by the alphabetical order, as are all characters other than
42letters. To look up your message, just ignore anything that is not a
43letter.
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44
45=over 4
46
6df41af2 47=item accept() on closed socket %s
33633739 48
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49(W closed) You tried to do an accept on a closed socket. Did you forget
50to check the return value of your socket() call? See
51L<perlfunc/accept>.
33633739 52
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53=item Aliasing via reference is experimental
54
55(S experimental::refaliasing) This warning is emitted if you use
56a reference constructor on the left-hand side of an assignment to
57alias one variable to another. Simply suppress the warning if you
58want to use the feature, but know that in doing so you are taking
59the risk of using an experimental feature which may change or be
60removed in a future Perl version:
61
62 no warnings "experimental::refaliasing";
63 use feature "refaliasing";
64 \$x = \$y;
65
de42a5a9 66=item Allocation too large: %x
a0d0e21e 67
6df41af2 68(X) You can't allocate more than 64K on an MS-DOS machine.
a0d0e21e 69
04f74579 70=item '%c' allowed only after types %s in %s
ef54e1a4 71
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72(F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
73after certain types. See L<perlfunc/pack>.
ef54e1a4 74
6df41af2 75=item Ambiguous call resolved as CORE::%s(), qualify as such or use &
43192e07 76
75b44862 77(W ambiguous) A subroutine you have declared has the same name as a Perl
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78keyword, and you have used the name without qualification for calling
79one or the other. Perl decided to call the builtin because the
80subroutine is not imported.
43192e07 81
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82To force interpretation as a subroutine call, either put an ampersand
83before the subroutine name, or qualify the name with its package.
84Alternatively, you can import the subroutine (or pretend that it's
85imported with the C<use subs> pragma).
43192e07 86
6df41af2 87To silently interpret it as the Perl operator, use the C<CORE::> prefix
496a33f5 88on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
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89to be an object method (see L<perlsub/"Subroutine Attributes"> or
90L<attributes>).
43192e07 91
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92=item Ambiguous range in transliteration operator
93
94(F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
95all. To include a C<-> character in a transliteration, put it either
96first or last. (In the past, C<tr/a-z-0//> was synonymous with
97C<tr/a-y//>, which was probably not what you would have expected.)
98
6df41af2 99=item Ambiguous use of %s resolved as %s
43192e07 100
7c7af292 101(S ambiguous) You said something that may not be interpreted the way
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102you thought. Normally it's pretty easy to disambiguate it by supplying
103a missing quote, operator, parenthesis pair or declaration.
a0d0e21e 104
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105=item Ambiguous use of -%s resolved as -&%s()
106
107(S ambiguous) You wrote something like C<-foo>, which might be the
108string C<"-foo">, or a call to the function C<foo>, negated. If you meant
109the string, just write C<"-foo">. If you meant the function call,
110write C<-foo()>.
111
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112=item Ambiguous use of %c resolved as operator %c
113
7c7af292 114(S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
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115bitwise and, and multiplication) I<and> initial special characters
116(denoting hashes, subroutines and typeglobs), and you said something
117like C<*foo * foo> that might be interpreted as either of them. We
118assumed you meant the infix operator, but please try to make it more
119clear -- in the example given, you might write C<*foo * foo()> if you
120really meant to multiply a glob by the result of calling a function.
d8225693 121
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122=item Ambiguous use of %c{%s} resolved to %c%s
123
124(W ambiguous) You wrote something like C<@{foo}>, which might be
125asking for the variable C<@foo>, or it might be calling a function
126named foo, and dereferencing it as an array reference. If you wanted
1cecf2c0 127the variable, you can just write C<@foo>. If you wanted to call the
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128function, write C<@{foo()}> ... or you could just not have a variable
129and a function with the same name, and save yourself a lot of trouble.
130
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131=item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
132
133=item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
4da60377 134
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135(W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
136the name of a Perl keyword), which might be looking for element number
1372 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
138might have meant to pass an anonymous arrayref to the function named
139foo, and then do a scalar deref on the value it returns. If you meant
140that, write C<${foo([2])}>.
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141
142In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
143to disambiguate between array subscripts and character classes.
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144C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
145by the character class C<[2345]>. If an array subscript is what you
146want, you can avoid the warning by changing C</${length[2345]}/> to the
147unsightly C</${\$length[2345]}/>, by renaming your array to something
148that does not coincide with a built-in keyword, or by simply turning
149off warnings with C<no warnings 'ambiguous';>.
4da60377 150
6df41af2 151=item '|' and '<' may not both be specified on command line
a0d0e21e 152
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153(F) An error peculiar to VMS. Perl does its own command line
154redirection, and found that STDIN was a pipe, and that you also tried to
155redirect STDIN using '<'. Only one STDIN stream to a customer, please.
c9f97d15 156
6df41af2 157=item '|' and '>' may not both be specified on command line
1028017a 158
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159(F) An error peculiar to VMS. Perl does its own command line
160redirection, and thinks you tried to redirect stdout both to a file and
161into a pipe to another command. You need to choose one or the other,
162though nothing's stopping you from piping into a program or Perl script
163which 'splits' output into two streams, such as
1028017a 164
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165 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
166 while (<STDIN>) {
167 print;
168 print OUT;
169 }
170 close OUT;
c9f97d15 171
6df41af2 172=item Applying %s to %s will act on scalar(%s)
eb6e2d6f 173
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174(W misc) The pattern match (C<//>), substitution (C<s///>), and
175transliteration (C<tr///>) operators work on scalar values. If you apply
be771a83 176one of them to an array or a hash, it will convert the array or hash to
ac036724 177a scalar value (the length of an array, or the population info of a
178hash) and then work on that scalar value. This is probably not what
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179you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
180alternatives.
eb6e2d6f 181
6df41af2 182=item Arg too short for msgsnd
76cd736e 183
6df41af2 184(F) msgsnd() requires a string at least as long as sizeof(long).
76cd736e 185
f86702cc 186=item Argument "%s" isn't numeric%s
a0d0e21e 187
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188(W numeric) The indicated string was fed as an argument to an operator
189that expected a numeric value instead. If you're fortunate the message
190will identify which operator was so unfortunate.
a0d0e21e 191
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192Note that for the C<Inf> and C<NaN> (infinity and not-a-number) the
193definition of "numeric" is somewhat unusual: the strings themselves
194(like "Inf") are considered numeric, and anything following them is
195considered non-numeric.
196
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197=item Argument list not closed for PerlIO layer "%s"
198
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199(W layer) When pushing a layer with arguments onto the Perl I/O
200system you forgot the ) that closes the argument list. (Layers
201take care of transforming data between external and internal
202representations.) Perl stopped parsing the layer list at this
203point and did not attempt to push this layer. If your program
204didn't explicitly request the failing operation, it may be the
205result of the value of the environment variable PERLIO.
b4581f09 206
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207=item Argument "%s" treated as 0 in increment (++)
208
209(W numeric) The indicated string was fed as an argument to the C<++>
210operator which expects either a number or a string matching
211C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
212Auto-decrement> for details.
213
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214=item assertion botched: %s
215
21b5e840 216(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 217
0eacef8e 218=item Assertion %s failed: file "%s", line %d
a0d0e21e 219
21b5e840 220(X) A general assertion failed. The file in question must be examined.
a0d0e21e 221
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222=item Assigned value is not a reference
223
224(F) You tried to assign something that was not a reference to an lvalue
225reference (e.g., C<\$x = $y>). If you meant to make $x an alias to $y, use
226C<\$x = \$y>.
227
228=item Assigned value is not %s reference
229
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230(F) You tried to assign a reference to a reference constructor, but the
231two references were not of the same type. You cannot alias a scalar to
232an array, or an array to a hash; the two types must match.
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233
234 \$x = \@y; # error
235 \@x = \%y; # error
236 $y = [];
237 \$x = $y; # error; did you mean \$y?
238
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239=item Assigning non-zero to $[ is no longer possible
240
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241(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
242the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 243
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244=item Assignment to both a list and a scalar
245
246(F) If you assign to a conditional operator, the 2nd and 3rd arguments
247must either both be scalars or both be lists. Otherwise Perl won't
248know which context to supply to the right side.
249
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250=item <> at require-statement should be quotes
251
252(F) You wrote C<< require <file> >> when you should have written
253C<require 'file'>.
254
2393f1b9 255=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 256
49293501 257(F) The failing code has attempted to get or set a key which is not in
2393f1b9 258the current set of allowed keys of a restricted hash.
49293501 259
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260=item Attempt to bless into a freed package
261
262(F) You wrote C<bless $foo> with one argument after somehow causing
263the current package to be freed. Perl cannot figure out what to
264do, so it throws up in hands in despair.
265
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266=item Attempt to bless into a reference
267
268(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 269the name of the package to bless the resulting object into. You've
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270supplied instead a reference to something: perhaps you wrote
271
272 bless $self, $proto;
273
274when you intended
275
276 bless $self, ref($proto) || $proto;
277
278If you actually want to bless into the stringified version
279of the reference supplied, you need to stringify it yourself, for
280example by:
281
282 bless $self, "$proto";
283
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284=item Attempt to clear deleted array
285
286(S debugging) An array was assigned to when it was being freed.
287Freed values are not supposed to be visible to Perl code. This
288can also happen if XS code calls C<av_clear> from a custom magic
289callback on the array.
290
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291=item Attempt to delete disallowed key '%s' from a restricted hash
292
293(F) The failing code attempted to delete from a restricted hash a key
294which is not in its key set.
295
296=item Attempt to delete readonly key '%s' from a restricted hash
297
298(F) The failing code attempted to delete a key whose value has been
299declared readonly from a restricted hash.
300
de42a5a9 301=item Attempt to free non-arena SV: 0x%x
a0d0e21e 302
f84fe999 303(S internal) All SV objects are supposed to be allocated from arenas
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304that will be garbage collected on exit. An SV was discovered to be
305outside any of those arenas.
a0d0e21e 306
12578ffb 307=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 308
f84fe999 309(S internal) Perl maintains a reference-counted internal table of
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310strings to optimize the storage and access of hash keys and other
311strings. This indicates someone tried to decrement the reference count
312of a string that can no longer be found in the table.
bbce6d69 313
7d5b40b4 314=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 315
f84fe999 316(S debugging) Mortalized values are supposed to be freed by the
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317free_tmps() routine. This indicates that something else is freeing the
318SV before the free_tmps() routine gets a chance, which means that the
319free_tmps() routine will be freeing an unreferenced scalar when it does
320try to free it.
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321
322=item Attempt to free unreferenced glob pointers
323
f84fe999 324(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 325
7d5b40b4 326=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 327
8f7e4d2c 328(S internal) Perl went to decrement the reference count of a scalar to
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329see if it would go to 0, and discovered that it had already gone to 0
330earlier, and should have been freed, and in fact, probably was freed.
331This could indicate that SvREFCNT_dec() was called too many times, or
332that SvREFCNT_inc() was called too few times, or that the SV was
333mortalized when it shouldn't have been, or that memory has been
334corrupted.
a0d0e21e 335
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336=item Attempt to pack pointer to temporary value
337
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338(W pack) You tried to pass a temporary value (like the result of a
339function, or a computed expression) to the "p" pack() template. This
340means the result contains a pointer to a location that could become
341invalid anytime, even before the end of the current statement. Use
342literals or global values as arguments to the "p" pack() template to
343avoid this warning.
84902520 344
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345=item Attempt to reload %s aborted.
346
347(F) You tried to load a file with C<use> or C<require> that failed to
348compile once already. Perl will not try to compile this file again
349unless you delete its entry from %INC. See L<perlfunc/require> and
350L<perlvar/%INC>.
351
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352=item Attempt to set length of freed array
353
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354(W misc) You tried to set the length of an array which has
355been freed. You can do this by storing a reference to the
356scalar representing the last index of an array and later
357assigning through that reference. For example
1b20cd17
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358
359 $r = do {my @a; \$#a};
360 $$r = 503
361
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362=item Attempt to use reference as lvalue in substr
363
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364(W substr) You supplied a reference as the first argument to substr()
365used as an lvalue, which is pretty strange. Perhaps you forgot to
366dereference it first. See L<perlfunc/substr>.
b7a902f4 367
c32124fe
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368=item Attribute "locked" is deprecated
369
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370(D deprecated) You have used the attributes pragma to modify the
371"locked" attribute on a code reference. The :locked attribute is
372obsolete, has had no effect since 5005 threads were removed, and
373will be removed in a future release of Perl 5.
c32124fe 374
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375=item Attribute prototype(%s) discards earlier prototype attribute in same sub
376
377(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
378example. Since each sub can only have one prototype, the earlier
379declaration(s) are discarded while the last one is applied.
380
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381=item Attribute "unique" is deprecated
382
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383(D deprecated) You have used the attributes pragma to modify
384the "unique" attribute on an array, hash or scalar reference.
385The :unique attribute has had no effect since Perl 5.8.8, and
386will be removed in a future release of Perl 5.
f1a3ce43 387
ccce04a4
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388=item av_reify called on tied array
389
390(S debugging) This indicates that something went wrong and Perl got I<very>
391confused about C<@_> or C<@DB::args> being tied.
392
de42a5a9 393=item Bad arg length for %s, is %u, should be %d
a0d0e21e 394
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395(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
396or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 397S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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398S<sizeof(struct shmid_ds *)>.
399
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400=item Bad evalled substitution pattern
401
496a33f5 402(F) You've used the C</e> switch to evaluate the replacement for a
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403substitution, but perl found a syntax error in the code to evaluate,
404most likely an unexpected right brace '}'.
405
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406=item Bad filehandle: %s
407
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408(F) A symbol was passed to something wanting a filehandle, but the
409symbol has no filehandle associated with it. Perhaps you didn't do an
410open(), or did it in another package.
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411
412=item Bad free() ignored
413
be771a83 414(S malloc) An internal routine called free() on something that had never
fa816bf3 415been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 416setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 417
9ea8bc6d 418This message can be seen quite often with DB_File on systems with "hard"
6903afa2 419dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 420which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 421
aa689395
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422=item Bad hash
423
424(P) One of the internal hash routines was passed a null HV pointer.
425
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426=item Badly placed ()'s
427
428(A) You've accidentally run your script through B<csh> instead
429of Perl. Check the #! line, or manually feed your script into
430Perl yourself.
431
a7cb8dae 432=item Bad name after %s
a0d0e21e 433
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434(F) You started to name a symbol by using a package prefix, and then
435didn't finish the symbol. In particular, you can't interpolate outside
436of quotes, so
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437
438 $var = 'myvar';
439 $sym = mypack::$var;
440
441is not the same as
442
443 $var = 'myvar';
444 $sym = "mypack::$var";
445
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446=item Bad plugin affecting keyword '%s'
447
448(F) An extension using the keyword plugin mechanism violated the
449plugin API.
450
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451=item Bad realloc() ignored
452
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453(S malloc) An internal routine called realloc() on something that
454had never been malloc()ed in the first place. Mandatory, but can
455be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 456
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457=item Bad symbol for array
458
459(P) An internal request asked to add an array entry to something that
460wasn't a symbol table entry.
461
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462=item Bad symbol for dirhandle
463
464(P) An internal request asked to add a dirhandle entry to something
465that wasn't a symbol table entry.
466
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467=item Bad symbol for filehandle
468
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469(P) An internal request asked to add a filehandle entry to something
470that wasn't a symbol table entry.
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471
472=item Bad symbol for hash
473
474(P) An internal request asked to add a hash entry to something that
475wasn't a symbol table entry.
476
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FC
477=item Bad symbol for scalar
478
479(P) An internal request asked to add a scalar entry to something that
480wasn't a symbol table entry.
481
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482=item Bareword found in conditional
483
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484(W bareword) The compiler found a bareword where it expected a
485conditional, which often indicates that an || or && was parsed as part
486of the last argument of the previous construct, for example:
34d09196
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487
488 open FOO || die;
489
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490It may also indicate a misspelled constant that has been interpreted as
491a bareword:
34d09196
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492
493 use constant TYPO => 1;
494 if (TYOP) { print "foo" }
495
496The C<strict> pragma is useful in avoiding such errors.
497
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498=item Bareword "%s" not allowed while "strict subs" in use
499
500(F) With "strict subs" in use, a bareword is only allowed as a
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501subroutine identifier, in curly brackets or to the left of the "=>"
502symbol. Perhaps you need to predeclare a subroutine?
6df41af2
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503
504=item Bareword "%s" refers to nonexistent package
505
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506(W bareword) You used a qualified bareword of the form C<Foo::>, but the
507compiler saw no other uses of that namespace before that point. Perhaps
508you need to predeclare a package?
6df41af2 509
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510=item BEGIN failed--compilation aborted
511
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512(F) An untrapped exception was raised while executing a BEGIN
513subroutine. Compilation stops immediately and the interpreter is
514exited.
a0d0e21e 515
68dc0745
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516=item BEGIN not safe after errors--compilation aborted
517
518(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
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519implies a C<BEGIN {}>) after one or more compilation errors had already
520occurred. Since the intended environment for the C<BEGIN {}> could not
521be guaranteed (due to the errors), and since subsequent code likely
522depends on its correct operation, Perl just gave up.
68dc0745 523
c782d7ee 524=item \%d better written as $%d
6df41af2 525
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526(W syntax) Outside of patterns, backreferences live on as variables.
527The use of backslashes is grandfathered on the right-hand side of a
528substitution, but stylistically it's better to use the variable form
529because other Perl programmers will expect it, and it works better if
530there are more than 9 backreferences.
6df41af2 531
252aa082
JH
532=item Binary number > 0b11111111111111111111111111111111 non-portable
533
e476b1b5 534(W portable) The binary number you specified is larger than 2**32-1
9e24b6e2
JH
535(4294967295) and therefore non-portable between systems. See
536L<perlport> for more on portability concerns.
252aa082 537
69282e91 538=item bind() on closed socket %s
a0d0e21e 539
be771a83
GS
540(W closed) You tried to do a bind on a closed socket. Did you forget to
541check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 542
c289d2f7
JH
543=item binmode() on closed filehandle %s
544
545(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 546Check your control flow and number of arguments.
c289d2f7 547
c5a0f51a
JH
548=item Bit vector size > 32 non-portable
549
e476b1b5 550(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 551
043c750c 552=item Bizarre copy of %s
4633a7c4 553
be771a83 554(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 555copiable.
4633a7c4 556
5a25739d
FC
557=item Bizarre SvTYPE [%d]
558
434f489b 559(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
560encountered an invalid data type.
561
b927b7e9 562=item Both or neither range ends should be Unicode in regex; marked by
6e8a73f2 563S<<-- HERE> in m/%s/
b927b7e9
KW
564
565(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
566
567In a bracketed character class in a regular expression pattern, you
568had a range which has exactly one end of it specified using C<\N{}>, and
569the other end is specified using a non-portable mechanism. Perl treats
570the range as a Unicode range, that is, all the characters in it are
571considered to be the Unicode characters, and which may be different code
572points on some platforms Perl runs on. For example, C<[\N{U+06}-\x08]>
573is treated as if you had instead said C<[\N{U+06}-\N{U+08}]>, that is it
574matches the characters whose code points in Unicode are 6, 7, and 8.
575But that C<\x08> might indicate that you meant something different, so
576the warning gets raised.
577
f675dbe5
CB
578=item Buffer overflow in prime_env_iter: %s
579
be771a83
GS
580(W internal) A warning peculiar to VMS. While Perl was preparing to
581iterate over %ENV, it encountered a logical name or symbol definition
582which was too long, so it was truncated to the string shown.
f675dbe5 583
a0d0e21e
LW
584=item Callback called exit
585
4929bf7b 586(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
587exited by calling exit.
588
6df41af2 589=item %s() called too early to check prototype
f675dbe5 590
be771a83
GS
591(W prototype) You've called a function that has a prototype before the
592parser saw a definition or declaration for it, and Perl could not check
593that the call conforms to the prototype. You need to either add an
594early prototype declaration for the subroutine in question, or move the
595subroutine definition ahead of the call to get proper prototype
596checking. Alternatively, if you are certain that you're calling the
597function correctly, you may put an ampersand before the name to avoid
598the warning. See L<perlsub>.
f675dbe5 599
56feebad
FC
600=item Calling POSIX::%s() is deprecated
601
602(D deprecated) You called a function whose use is deprecated. See
603the function's name in L<POSIX> for details.
604
0c7df902
JH
605=item Cannot chr %f
606
607(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
608
5dee29d4 609=item Cannot compress %f in pack
0c7df902 610
5dee29d4
JH
611(F) You tried compressing an infinity or not-a-number as an unsigned
612integer with BER, which makes no sense.
0c7df902 613
49704364 614=item Cannot compress integer in pack
0258719b 615
717feafc
JH
616(F) An argument to pack("w",...) was too large to compress.
617The BER compressed integer format can only be used with positive
618integers, and you attempted to compress a very large number (> 1e308).
619See L<perlfunc/pack>.
0258719b 620
49704364 621=item Cannot compress negative numbers in pack
0258719b
NC
622
623(F) An argument to pack("w",...) was negative. The BER compressed integer
624format can only be used with positive integers. See L<perlfunc/pack>.
625
5c1f4d79
NC
626=item Cannot convert a reference to %s to typeglob
627
6903afa2
FC
628(F) You manipulated Perl's symbol table directly, stored a reference
629in it, then tried to access that symbol via conventional Perl syntax.
630The access triggers Perl to autovivify that typeglob, but it there is
631no legal conversion from that type of reference to a typeglob.
5c1f4d79 632
4040665a 633=item Cannot copy to %s
ba2fdce6
NC
634
635(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 636be directly assigned to.
ba2fdce6 637
b5d97229
RGS
638=item Cannot find encoding "%s"
639
640(S io) You tried to apply an encoding that did not exist to a filehandle,
641either with open() or binmode().
642
0c7df902
JH
643=item Cannot pack %f with '%c'
644
5dee29d4 645(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
646which makes no sense.
647
648=item Cannot printf %f with '%c'
649
650(F) You tried printing an infinity or not-a-number as a character (%c),
651which makes no sense. Maybe you meant '%s', or just stringifying it?
652
7355df7e
FC
653=item Cannot set tied @DB::args
654
655(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
656is not supported. (Before this error was added, it used to crash.)
657
ce65bc73
FC
658=item Cannot tie unreifiable array
659
660(P) You somehow managed to call C<tie> on an array that does not
661keep a reference count on its arguments and cannot be made to
662do so. Such arrays are not even supposed to be accessible to
663Perl code, but are only used internally.
664
96ebfdd7
RK
665=item Can only compress unsigned integers in pack
666
667(F) An argument to pack("w",...) was not an integer. The BER compressed
668integer format can only be used with positive integers, and you attempted
669to compress something else. See L<perlfunc/pack>.
670
a0d0e21e
LW
671=item Can't bless non-reference value
672
673(F) Only hard references may be blessed. This is how Perl "enforces"
674encapsulation of objects. See L<perlobj>.
675
dc57907a
RGS
676=item Can't "break" in a loop topicalizer
677
0d863452 678(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 679a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
680
681=item Can't "break" outside a given block
dc57907a 682
0d863452
RH
683(F) You called C<break>, but you're not inside a C<given> block.
684
6df41af2
GS
685=item Can't call method "%s" on an undefined value
686
687(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
688object reference or package name contains an undefined value. Something
689like this will reproduce the error:
6df41af2
GS
690
691 $BADREF = undef;
692 process $BADREF 1,2,3;
693 $BADREF->process(1,2,3);
694
a0d0e21e
LW
695=item Can't call method "%s" on unblessed reference
696
54310121 697(F) A method call must know in what package it's supposed to run. It
be771a83
GS
698ordinarily finds this out from the object reference you supply, but you
699didn't supply an object reference in this case. A reference isn't an
700object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
701
702=item Can't call method "%s" without a package or object reference
703
704(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
705object reference or package name contains an expression that returns a
706defined value which is neither an object reference nor a package name.
72b5445b
GS
707Something like this will reproduce the error:
708
709 $BADREF = 42;
710 process $BADREF 1,2,3;
711 $BADREF->process(1,2,3);
712
dfe378f1
FC
713=item Can't call mro_isa_changed_in() on anonymous symbol table
714
715(P) Perl got confused as to whether a hash was a plain hash or a
716symbol table hash when trying to update @ISA caches.
717
2bf7e7b2
FC
718=item Can't call mro_method_changed_in() on anonymous symbol table
719
720(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
721not attached to the symbol table.
722
a0d0e21e
LW
723=item Can't chdir to %s
724
f703fc96 725(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
726that you can chdir to, possibly because it doesn't exist.
727
0545a864 728=item Can't check filesystem of script "%s" for nosuid
104d25b7 729
be771a83
GS
730(P) For some reason you can't check the filesystem of the script for
731nosuid.
104d25b7 732
22e74366 733=item Can't coerce %s to %s in %s
a0d0e21e
LW
734
735(F) Certain types of SVs, in particular real symbol table entries
55497cff 736(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
737say things like:
738
739 *foo += 1;
740
741You CAN say
742
743 $foo = *foo;
744 $foo += 1;
745
746but then $foo no longer contains a glob.
747
0d863452 748=item Can't "continue" outside a when block
dc57907a 749
0d863452
RH
750(F) You called C<continue>, but you're not inside a C<when>
751or C<default> block.
752
a0d0e21e
LW
753=item Can't create pipe mailbox
754
be771a83
GS
755(P) An error peculiar to VMS. The process is suffering from exhausted
756quotas or other plumbing problems.
a0d0e21e 757
eb64745e
GS
758=item Can't declare %s in "%s"
759
30c282f6
NC
760(F) Only scalar, array, and hash variables may be declared as "my", "our" or
761"state" variables. They must have ordinary identifiers as names.
a0d0e21e 762
fc7debfb
FC
763=item Can't "default" outside a topicalizer
764
765(F) You have used a C<default> block that is neither inside a
766C<foreach> loop nor a C<given> block. (Note that this error is
767issued on exit from the C<default> block, so you won't get the
768error if you use an explicit C<continue>.)
769
a2162cd9
FC
770=item Can't do inplace edit: %s is not a regular file
771
772(S inplace) You tried to use the B<-i> switch on a special file, such as
773a file in /dev, a FIFO or an uneditable directory. The file was ignored.
774
775=item Can't do inplace edit on %s: %s
776
777(S inplace) The creation of the new file failed for the indicated
778reason.
779
780=item Can't do inplace edit without backup
781
782(F) You're on a system such as MS-DOS that gets confused if you try
783reading from a deleted (but still opened) file. You have to say
784C<-i.bak>, or some such.
785
786=item Can't do inplace edit: %s would not be unique
787
788(S inplace) Your filesystem does not support filenames longer than 14
789characters and Perl was unable to create a unique filename during
790inplace editing with the B<-i> switch. The file was ignored.
791
ab0b796c
KW
792=item Can't do %s("%s") on non-UTF-8 locale; resolved to "%s".
793
794(W locale) You are 1) running under "C<use locale>"; 2) the current
795locale is not a UTF-8 one; 3) you tried to do the designated case-change
796operation on the specified Unicode character; and 4) the result of this
797operation would mix Unicode and locale rules, which likely conflict.
798Mixing of different rule types is forbidden, so the operation was not
799done; instead the result is the indicated value, which is the best
800available that uses entirely Unicode rules. That turns out to almost
801always be the original character, unchanged.
802
803It is generally a bad idea to mix non-UTF-8 locales and Unicode, and
804this issue is one of the reasons why. This warning is raised when
805Unicode rules would normally cause the result of this operation to
806contain a character that is in the range specified by the locale,
8070..255, and hence is subject to the locale's rules, not Unicode's.
808
809If you are using locale purely for its characteristics related to things
810like its numeric and time formatting (and not C<LC_CTYPE>), consider
811using a restricted form of the locale pragma (see L<perllocale/The "use
812locale" pragma>) like "S<C<use locale ':not_characters'>>".
813
814Note that failed case-changing operations done as a result of
815case-insensitive C</i> regular expression matching will show up in this
816warning as having the C<fc> operation (as that is what the regular
817expression engine calls behind the scenes.)
818
a0d0e21e
LW
819=item Can't do waitpid with flags
820
be771a83
GS
821(F) This machine doesn't have either waitpid() or wait4(), so only
822waitpid() without flags is emulated.
a0d0e21e 823
a0d0e21e
LW
824=item Can't emulate -%s on #! line
825
be771a83
GS
826(F) The #! line specifies a switch that doesn't make sense at this
827point. For example, it'd be kind of silly to put a B<-x> on the #!
828line.
a0d0e21e 829
1109a392
MHM
830=item Can't %s %s-endian %ss on this platform
831
832(F) Your platform's byte-order is neither big-endian nor little-endian,
833or it has a very strange pointer size. Packing and unpacking big- or
834little-endian floating point values and pointers may not be possible.
835See L<perlfunc/pack>.
836
a0d0e21e
LW
837=item Can't exec "%s": %s
838
d1be9408 839(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
840named program for the indicated reason. Typical reasons include: the
841permissions were wrong on the file, the file wasn't found in
842C<$ENV{PATH}>, the executable in question was compiled for another
843architecture, or the #! line in a script points to an interpreter that
844can't be run for similar reasons. (Or maybe your system doesn't support
845#! at all.)
a0d0e21e
LW
846
847=item Can't exec %s
848
be771a83
GS
849(F) Perl was trying to execute the indicated program for you because
850that's what the #! line said. If that's not what you wanted, you may
851need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
852
853=item Can't execute %s
854
be771a83
GS
855(F) You used the B<-S> switch, but the copies of the script to execute
856found in the PATH did not have correct permissions.
2a92aaa0 857
6df41af2 858=item Can't find an opnumber for "%s"
2a92aaa0 859
be771a83
GS
860(F) A string of a form C<CORE::word> was given to prototype(), but there
861is no builtin with the name C<word>.
6df41af2 862
56ca2fc0
JH
863=item Can't find %s character property "%s"
864
865(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 866could not be found. Maybe you misspelled the name of the property?
e1b711da 867See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 868for a complete list of available official properties.
56ca2fc0 869
6df41af2
GS
870=item Can't find label %s
871
be771a83
GS
872(F) You said to goto a label that isn't mentioned anywhere that it's
873possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
874
875=item Can't find %s on PATH
876
be771a83
GS
877(F) You used the B<-S> switch, but the script to execute could not be
878found in the PATH.
a0d0e21e 879
6df41af2 880=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 881
be771a83
GS
882(F) You used the B<-S> switch, but the script to execute could not be
883found in the PATH, or at least not with the correct permissions. The
884script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
885
886=item Can't find string terminator %s anywhere before EOF
887
be771a83
GS
888(F) Perl strings can stretch over multiple lines. This message means
889that the closing delimiter was omitted. Because bracketed quotes count
890nesting levels, the following is missing its final parenthesis:
a0d0e21e 891
fb73857a
PP
892 print q(The character '(' starts a side comment.);
893
97b3d10f 894If you're getting this error from a here-document, you may have
b6b8cb97
FC
895included unseen whitespace before or after your closing tag or there
896may not be a linebreak after it. A good programmer's editor will have
897a way to help you find these characters (or lack of characters). See
898L<perlop> for the full details on here-documents.
a0d0e21e 899
660a4616
ST
900=item Can't find Unicode property definition "%s"
901
5f8ad6b6
FC
902(F) You may have tried to use C<\p> which means a Unicode
903property (for example C<\p{Lu}> matches all uppercase
fa816bf3 904letters). If you did mean to use a Unicode property, see
e1b711da 905L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 906for a complete list of available properties. If you didn't
fa816bf3
FC
907mean to use a Unicode property, escape the C<\p>, either by
908C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 909until C<\E>).
660a4616 910
b3647a36 911=item Can't fork: %s
a0d0e21e 912
be771a83
GS
913(F) A fatal error occurred while trying to fork while opening a
914pipeline.
a0d0e21e 915
b3647a36
SR
916=item Can't fork, trying again in 5 seconds
917
c973c02e 918(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
919after five seconds.
920
748a9306
LW
921=item Can't get filespec - stale stat buffer?
922
be771a83
GS
923(S) A warning peculiar to VMS. This arises because of the difference
924between access checks under VMS and under the Unix model Perl assumes.
925Under VMS, access checks are done by filename, rather than by bits in
926the stat buffer, so that ACLs and other protections can be taken into
927account. Unfortunately, Perl assumes that the stat buffer contains all
928the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 929the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
930the device name and FID present in the stat buffer, but this works only
931if you haven't made a subsequent call to the CRTL stat() routine,
932because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
933appears, the name lookup failed, and the access-checking routine gave up
934and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
935routine knows about the Perl C<stat> operator and file tests, so you
936shouldn't ever see this warning in response to a Perl command; it arises
937only if some internal code takes stat buffers lightly.)
748a9306 938
a0d0e21e
LW
939=item Can't get pipe mailbox device name
940
be771a83
GS
941(P) An error peculiar to VMS. After creating a mailbox to act as a
942pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
943
944=item Can't get SYSGEN parameter value for MAXBUF
945
748a9306
LW
946(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
947mailbox buffers to be, and didn't get an answer.
a0d0e21e 948
6df41af2 949=item Can't "goto" into the middle of a foreach loop
a0d0e21e 950
be771a83
GS
951(F) A "goto" statement was executed to jump into the middle of a foreach
952loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
953
954=item Can't "goto" out of a pseudo block
955
be771a83
GS
956(F) A "goto" statement was executed to jump out of what might look like
957a block, except that it isn't a proper block. This usually occurs if
958you tried to jump out of a sort() block or subroutine, which is a no-no.
959See L<perlfunc/goto>.
a0d0e21e 960
5a25739d
FC
961=item Can't goto subroutine from an eval-%s
962
963(F) The "goto subroutine" call can't be used to jump out of an eval
964"string" or block.
965
9850bf21 966=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 967
9850bf21
RH
968(F) The "goto subroutine" call can't be used to jump out of the
969comparison sub for a sort(), or from a similar callback (such
970as the reduce() function in List::Util).
971
6df41af2
GS
972=item Can't goto subroutine outside a subroutine
973
be771a83
GS
974(F) The deeply magical "goto subroutine" call can only replace one
975subroutine call for another. It can't manufacture one out of whole
976cloth. In general you should be calling it out of only an AUTOLOAD
977routine anyway. See L<perlfunc/goto>.
6df41af2 978
0b5b802d
GS
979=item Can't ignore signal CHLD, forcing to default
980
be771a83
GS
981(W signal) Perl has detected that it is being run with the SIGCHLD
982signal (sometimes known as SIGCLD) disabled. Since disabling this
983signal will interfere with proper determination of exit status of child
984processes, Perl has reset the signal to its default value. This
985situation typically indicates that the parent program under which Perl
986may be running (e.g. cron) is being very careless.
0b5b802d 987
e2c0f81f
DG
988=item Can't kill a non-numeric process ID
989
990(F) Process identifiers must be (signed) integers. It is a fatal error to
991attempt to kill() an undefined, empty-string or otherwise non-numeric
992process identifier.
993
6df41af2 994=item Can't "last" outside a loop block
4633a7c4 995
6df41af2 996(F) A "last" statement was executed to break out of the current block,
be771a83
GS
997except that there's this itty bitty problem called there isn't a current
998block. Note that an "if" or "else" block doesn't count as a "loopish"
999block, as doesn't a block given to sort(), map() or grep(). You can
1000usually double the curlies to get the same effect though, because the
1001inner curlies will be considered a block that loops once. See
1002L<perlfunc/last>.
4633a7c4 1003
2c7d6b9c
RGS
1004=item Can't linearize anonymous symbol table
1005
1006(F) Perl tried to calculate the method resolution order (MRO) of a
1007package, but failed because the package stash has no name.
1008
b8170e59
JB
1009=item Can't load '%s' for module %s
1010
6903afa2
FC
1011(F) The module you tried to load failed to load a dynamic extension.
1012This may either mean that you upgraded your version of perl to one
1013that is incompatible with your old dynamic extensions (which is known
1014to happen between major versions of perl), or (more likely) that your
1015dynamic extension was built against an older version of the library
1016that is installed on your system. You may need to rebuild your old
1017dynamic extensions.
b8170e59 1018
748a9306
LW
1019=item Can't localize lexical variable %s
1020
2ba9eb46 1021(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
1022lexical variable using "my" or "state". This is not allowed. If you
1023want to localize a package variable of the same name, qualify it with
1024the package name.
748a9306 1025
6df41af2 1026=item Can't localize through a reference
4727527e 1027
6df41af2
GS
1028(F) You said something like C<local $$ref>, which Perl can't currently
1029handle, because when it goes to restore the old value of whatever $ref
be771a83 1030pointed to after the scope of the local() is finished, it can't be sure
64977eb6 1031that $ref will still be a reference.
4727527e 1032
ea071790 1033=item Can't locate %s
ec889f3a 1034
fa816bf3
FC
1035(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
1036Perl looks for the file in all the locations mentioned in @INC, unless
1037the file name included the full path to the file. Perhaps you need
1038to set the PERL5LIB or PERL5OPT environment variable to say where the
1039extra library is, or maybe the script needs to add the library name
be771a83
GS
1040to @INC. Or maybe you just misspelled the name of the file. See
1041L<perlfunc/require> and L<lib>.
a0d0e21e 1042
6df41af2
GS
1043=item Can't locate auto/%s.al in @INC
1044
be771a83
GS
1045(F) A function (or method) was called in a package which allows
1046autoload, but there is no function to autoload. Most probable causes
1047are a misprint in a function/method name or a failure to C<AutoSplit>
1048the file, say, by doing C<make install>.
6df41af2 1049
b8170e59
JB
1050=item Can't locate loadable object for module %s in @INC
1051
1052(F) The module you loaded is trying to load an external library, like
d70d8e57 1053for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1054unable to locate this library. See L<DynaLoader>.
1055
a0d0e21e
LW
1056=item Can't locate object method "%s" via package "%s"
1057
1058(F) You called a method correctly, and it correctly indicated a package
1059functioning as a class, but that package doesn't define that particular
2ba9eb46 1060method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1061
8af56b9d
FC
1062=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1063to load "%s"?)
1064
1065(F) You called a method on a class that did not exist, and the method
1066could not be found in UNIVERSAL. This often means that a method
1067requires a package that has not been loaded.
1068
a0d0e21e
LW
1069=item Can't locate package %s for @%s::ISA
1070
be771a83
GS
1071(W syntax) The @ISA array contained the name of another package that
1072doesn't seem to exist.
a0d0e21e 1073
2f7da168
RK
1074=item Can't locate PerlIO%s
1075
1076(F) You tried to use in open() a PerlIO layer that does not exist,
1077e.g. open(FH, ">:nosuchlayer", "somefile").
1078
f4ad53f4 1079=item Can't make list assignment to %ENV on this system
3e3baf6d 1080
be771a83
GS
1081(F) List assignment to %ENV is not supported on some systems, notably
1082VMS.
3e3baf6d 1083
cd40cd58
NC
1084=item Can't make loaded symbols global on this platform while loading %s
1085
ff9c1ae8 1086(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1087that symbols from the stated file are made available globally within the
1088process, but that functionality is not available on this platform. Whilst
1089the module likely will still work, this may prevent the perl interpreter
1090from loading other XS-based extensions which need to link directly to
1091functions defined in the C or XS code in the stated file.
1092
a0d0e21e
LW
1093=item Can't modify %s in %s
1094
be771a83
GS
1095(F) You aren't allowed to assign to the item indicated, or otherwise try
1096to change it, such as with an auto-increment.
a0d0e21e 1097
54310121 1098=item Can't modify nonexistent substring
a0d0e21e
LW
1099
1100(P) The internal routine that does assignment to a substr() was handed
1101a NULL.
1102
6df41af2
GS
1103=item Can't modify non-lvalue subroutine call
1104
1105(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1106such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1107
cf6e1fa1
FC
1108=item Can't modify reference to %s in %s assignment
1109
1110(F) Only a limited number of constructs can be used as the argument to a
1111reference constructor on the left-hand side of an assignment, and what
1112you used was not one of them. See L<perlref/Assigning to References>.
1113
1114=item Can't modify reference to localized parenthesized array in list
1115assignment
1116
1117(F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1118it is not clear exactly what it should do. If you meant to make @array
1119refer to some other array, use C<\@array = \@other_array>. If you want to
1120make the elements of @array aliases of the scalars referenced on the
1121right-hand side, use C<\(@array) = @scalar_refs>.
1122
1123=item Can't modify reference to parenthesized hash in list assignment
1124
1125(F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1126refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1127make the elements of %hash into aliases of the scalars referenced on the
1128right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1129
5f05dabc 1130=item Can't msgrcv to read-only var
a0d0e21e 1131
5f05dabc 1132(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1133buffer.
1134
6df41af2
GS
1135=item Can't "next" outside a loop block
1136
1137(F) A "next" statement was executed to reiterate the current block, but
1138there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1139count as a "loopish" block, as doesn't a block given to sort(), map() or
1140grep(). You can usually double the curlies to get the same effect
1141though, because the inner curlies will be considered a block that loops
1142once. See L<perlfunc/next>.
6df41af2 1143
a0d0e21e
LW
1144=item Can't open %s: %s
1145
c47ff5f1 1146(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1147filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1148switches, or explicitly, failed for the indicated reason. Usually
1149this is because you don't have read permission for a file which
1150you named on the command line.
1151
1152(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1153your operating system's equivalent) could not be opened.
a0d0e21e 1154
9a869a14
RGS
1155=item Can't open a reference
1156
1157(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1158using the 3-arg open() syntax:
9a869a14
RGS
1159
1160 open FH, '>', $ref;
1161
1162but your version of perl is compiled without perlio, and this form of
1163open is not supported.
1164
a0d0e21e
LW
1165=item Can't open bidirectional pipe
1166
be771a83
GS
1167(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1168You can try any of several modules in the Perl library to do this, such
1169as IPC::Open2. Alternately, direct the pipe's output to a file using
1170">", and then read it in under a different file handle.
a0d0e21e 1171
748a9306
LW
1172=item Can't open error file %s as stderr
1173
be771a83
GS
1174(F) An error peculiar to VMS. Perl does its own command line
1175redirection, and couldn't open the file specified after '2>' or '2>>' on
1176the command line for writing.
748a9306
LW
1177
1178=item Can't open input file %s as stdin
1179
be771a83
GS
1180(F) An error peculiar to VMS. Perl does its own command line
1181redirection, and couldn't open the file specified after '<' on the
1182command line for reading.
748a9306
LW
1183
1184=item Can't open output file %s as stdout
1185
be771a83
GS
1186(F) An error peculiar to VMS. Perl does its own command line
1187redirection, and couldn't open the file specified after '>' or '>>' on
1188the command line for writing.
748a9306
LW
1189
1190=item Can't open output pipe (name: %s)
1191
be771a83
GS
1192(P) An error peculiar to VMS. Perl does its own command line
1193redirection, and couldn't open the pipe into which to send data destined
1194for stdout.
748a9306 1195
3b1cf97d 1196=item Can't open perl script "%s": %s
a0d0e21e
LW
1197
1198(F) The script you specified can't be opened for the indicated reason.
1199
fa3aa65a
JC
1200If you're debugging a script that uses #!, and normally relies on the
1201shell's $PATH search, the -S option causes perl to do that search, so
1202you don't have to type the path or C<`which $scriptname`>.
1203
6df41af2
GS
1204=item Can't read CRTL environ
1205
1206(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1207from the CRTL's internal environment array and discovered the array was
1208missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1209or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1210searched.
6df41af2 1211
6df41af2
GS
1212=item Can't "redo" outside a loop block
1213
1214(F) A "redo" statement was executed to restart the current block, but
1215there isn't a current block. Note that an "if" or "else" block doesn't
1216count as a "loopish" block, as doesn't a block given to sort(), map()
1217or grep(). You can usually double the curlies to get the same effect
1218though, because the inner curlies will be considered a block that
1219loops once. See L<perlfunc/redo>.
1220
64977eb6 1221=item Can't remove %s: %s, skipping file
10f9c03d 1222
be771a83
GS
1223(S inplace) You requested an inplace edit without creating a backup
1224file. Perl was unable to remove the original file to replace it with
1225the modified file. The file was left unmodified.
10f9c03d 1226
a0d0e21e
LW
1227=item Can't rename %s to %s: %s, skipping file
1228
e476b1b5 1229(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1230probably because you don't have write permission to the directory.
a0d0e21e 1231
748a9306
LW
1232=item Can't reopen input pipe (name: %s) in binary mode
1233
be771a83
GS
1234(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1235to reopen it to accept binary data. Alas, it failed.
748a9306 1236
9415f659
KW
1237=item Can't represent character for Ox%X on this platform
1238
1239(F) There is a hard limit to how big a character code point can be due
1240to the fundamental properties of UTF-8, especially on EBCDIC
1241platforms. The given code point exceeds that. The only work-around is
1242to not use such a large code point.
1243
4f12ec0e
FC
1244=item Can't reset %ENV on this system
1245
1246(F) You called C<reset('E')> or similar, which tried to reset
1247all variables in the current package beginning with "E". In
1248the main package, that includes %ENV. Resetting %ENV is not
1249supported on some systems, notably VMS.
1250
fe13d51d 1251=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1252
1fa582fa
FC
1253(F)(P) Error resolving overloading specified by a method name (as
1254opposed to a subroutine reference): no such method callable via the
1255package. If the method name is C<???>, this is an internal error.
6df41af2 1256
cd06dffe
GS
1257=item Can't return %s from lvalue subroutine
1258
be771a83
GS
1259(F) Perl detected an attempt to return illegal lvalues (such as
1260temporary or readonly values) from a subroutine used as an lvalue. This
1261is not allowed.
cd06dffe 1262
96ebfdd7
RK
1263=item Can't return outside a subroutine
1264
1265(F) The return statement was executed in mainline code, that is, where
1266there was no subroutine call to return out of. See L<perlsub>.
1267
78f9721b
SM
1268=item Can't return %s to lvalue scalar context
1269
6903afa2
FC
1270(F) You tried to return a complete array or hash from an lvalue
1271subroutine, but you called the subroutine in a way that made Perl
1272think you meant to return only one value. You probably meant to
1273write parentheses around the call to the subroutine, which tell
1274Perl that the call should be in list context.
78f9721b 1275
a0d0e21e
LW
1276=item Can't stat script "%s"
1277
be771a83
GS
1278(P) For some reason you can't fstat() the script even though you have it
1279open already. Bizarre.
a0d0e21e 1280
a0d0e21e
LW
1281=item Can't take log of %g
1282
fb73857a 1283(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1284negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1285standard with Perl, though, if you really want to do that for the
1286negative numbers.
a0d0e21e
LW
1287
1288=item Can't take sqrt of %g
1289
1290(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1291negative number. There's a Math::Complex package that comes standard
1292with Perl, though, if you really want to do that.
a0d0e21e
LW
1293
1294=item Can't undef active subroutine
1295
1296(F) You can't undefine a routine that's currently running. You can,
1297however, redefine it while it's running, and you can even undef the
1298redefined subroutine while the old routine is running. Go figure.
1299
c81225bc 1300=item Can't upgrade %s (%d) to %d
a0d0e21e 1301
be771a83
GS
1302(P) The internal sv_upgrade routine adds "members" to an SV, making it
1303into a more specialized kind of SV. The top several SV types are so
1304specialized, however, that they cannot be interconverted. This message
1305indicates that such a conversion was attempted.
a0d0e21e 1306
6651ba0b
FC
1307=item Can't use '%c' after -mname
1308
1309(F) You tried to call perl with the B<-m> switch, but you put something
1310other than "=" after the module name.
1311
1f1ec7b5
KW
1312=item Can't use a hash as a reference
1313
1314(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1315C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1316<= 5.22.0 used to allow this syntax, but shouldn't
1317have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1318
1319=item Can't use an array as a reference
1320
1321(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1322C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1323used to allow this syntax, but shouldn't have. This
1324was deprecated in perl 5.6.1.
1f1ec7b5 1325
1db89ea5
BS
1326=item Can't use anonymous symbol table for method lookup
1327
e27ad1f2 1328(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1329table that doesn't have a name. Symbol tables can become anonymous
1330for example by undefining stashes: C<undef %Some::Package::>.
1331
96ebfdd7
RK
1332=item Can't use an undefined value as %s reference
1333
1334(F) A value used as either a hard reference or a symbolic reference must
1335be a defined value. This helps to delurk some insidious errors.
1336
6df41af2
GS
1337=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1338
be771a83
GS
1339(F) Only hard references are allowed by "strict refs". Symbolic
1340references are disallowed. See L<perlref>.
6df41af2 1341
90b75b61 1342=item Can't use %! because Errno.pm is not available
1d2dff63 1343
20561843 1344(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1345Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1346provide symbolic names for C<$!> errno values.
1347
1109a392
MHM
1348=item Can't use both '<' and '>' after type '%c' in %s
1349
1350(F) A type cannot be forced to have both big-endian and little-endian
1351byte-order at the same time, so this combination of modifiers is not
1352allowed. See L<perlfunc/pack>.
1353
e35475de
KW
1354=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1355
1356(F) defined() is not useful on arrays because it
1357checks for an undefined I<scalar> value. If you want to see if the
1358array is empty, just use C<if (@array) { # not empty }> for example.
1359
1360=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1361
1362(F) C<defined()> is not usually right on hashes.
1363
1364Although C<defined %hash> is false on a plain not-yet-used hash, it
1365becomes true in several non-obvious circumstances, including iterators,
1366weak references, stash names, even remaining true after C<undef %hash>.
1367These things make C<defined %hash> fairly useless in practice, so it now
1368generates a fatal error.
1369
1370If a check for non-empty is what you wanted then just put it in boolean
1371context (see L<perldata/Scalar values>):
1372
1373 if (%hash) {
1374 # not empty
1375 }
1376
1377If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1378variable exists then that's never really been reliable, and isn't
1379a good way to enquire about the features of a package, or whether
1380it's loaded, etc.
1381
6df41af2
GS
1382=item Can't use %s for loop variable
1383
c1f06047 1384(P) The parser got confused when trying to parse a C<foreach> loop.
6df41af2 1385
aab6a793 1386=item Can't use global %s in "%s"
6df41af2 1387
be771a83
GS
1388(F) You tried to declare a magical variable as a lexical variable. This
1389is not allowed, because the magic can be tied to only one location
1390(namely the global variable) and it would be incredibly confusing to
1391have variables in your program that looked like magical variables but
6df41af2
GS
1392weren't.
1393
6d3b25aa
RGS
1394=item Can't use '%c' in a group with different byte-order in %s
1395
1396(F) You attempted to force a different byte-order on a type
1397that is already inside a group with a byte-order modifier.
1398For example you cannot force little-endianness on a type that
1399is inside a big-endian group.
1400
c07a80fd
PP
1401=item Can't use "my %s" in sort comparison
1402
1403(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1404You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1405and the variable had earlier been declared as a lexical variable.
1406Either qualify the sort variable with the package name, or rename the
1407lexical variable.
1408
a0d0e21e
LW
1409=item Can't use %s ref as %s ref
1410
1411(F) You've mixed up your reference types. You have to dereference a
1412reference of the type needed. You can use the ref() function to
1413test the type of the reference, if need be.
1414
748a9306 1415=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1416
5e634d20
FC
1417=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1418
b41bf23f
FC
1419(F) You've told Perl to dereference a string, something which
1420C<use strict> blocks to prevent it happening accidentally. See
1421L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1422in a double-quoted string immediately before interpolating a variable,
1423for example in C<"user @$twitter_id">, which says to treat the contents
1424of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1425symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1426
748a9306
LW
1427=item Can't use subscript on %s
1428
1429(F) The compiler tried to interpret a bracketed expression as a
1430subscript. But to the left of the brackets was an expression that
209e7cf1 1431didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1432
6df41af2
GS
1433=item Can't use \%c to mean $%c in expression
1434
75b44862
GS
1435(W syntax) In an ordinary expression, backslash is a unary operator that
1436creates a reference to its argument. The use of backslash to indicate a
1437backreference to a matched substring is valid only as part of a regular
be771a83
GS
1438expression pattern. Trying to do this in ordinary Perl code produces a
1439value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1440instead.
6df41af2 1441
810b8aa5
GS
1442=item Can't weaken a nonreference
1443
1444(F) You attempted to weaken something that was not a reference. Only
1445references can be weakened.
1446
fc7debfb
FC
1447=item Can't "when" outside a topicalizer
1448
1449(F) You have used a when() block that is neither inside a C<foreach>
1450loop nor a C<given> block. (Note that this error is issued on exit
1451from the C<when> block, so you won't get the error if the match fails,
1452or if you use an explicit C<continue>.)
1453
5f05dabc 1454=item Can't x= to read-only value
a0d0e21e 1455
be771a83
GS
1456(F) You tried to repeat a constant value (often the undefined value)
1457with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1458Perhaps you need to copy the value to a temporary, and repeat that.
1459
a04e6aad 1460=item Character following "\c" must be printable ASCII
f9d13529 1461
7357bd17 1462(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1463
727b6379 1464Note that ASCII characters that don't map to control characters are
7357bd17 1465discouraged, and will generate the warning (when enabled)
727b6379 1466L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1467
f337b084 1468=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1469
1470(W pack) You said
1471
1472 pack("C", $x)
1473
1474where $x is either less than 0 or more than 255; the C<"C"> format is
1475only for encoding native operating system characters (ASCII, EBCDIC,
1476and so on) and not for Unicode characters, so Perl behaved as if you meant
1477
1478 pack("C", $x & 255)
1479
1480If you actually want to pack Unicode codepoints, use the C<"U"> format
1481instead.
1482
f337b084 1483=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1484
1485(W pack) You said
1486
1487 pack("c", $x)
1488
1489where $x is either less than -128 or more than 127; the C<"c"> format
1490is only for encoding native operating system characters (ASCII, EBCDIC,
1491and so on) and not for Unicode characters, so Perl behaved as if you meant
1492
1493 pack("c", $x & 255);
1494
1495If you actually want to pack Unicode codepoints, use the C<"U"> format
1496instead.
1497
f337b084
TH
1498=item Character in '%c' format wrapped in unpack
1499
1500(W unpack) You tried something like
1501
1502 unpack("H", "\x{2a1}")
1503
1a147d38 1504where the format expects to process a byte (a character with a value
6903afa2
FC
1505below 256), but a higher value was provided instead. Perl uses the
1506value modulus 256 instead, as if you had provided:
f337b084
TH
1507
1508 unpack("H", "\x{a1}")
1509
5a25739d
FC
1510=item Character in 'W' format wrapped in pack
1511
1512(W pack) You said
1513
1514 pack("U0W", $x)
1515
1516where $x is either less than 0 or more than 255. However, C<U0>-mode
1517expects all values to fall in the interval [0, 255], so Perl behaved
1518as if you meant:
1519
1520 pack("U0W", $x & 255)
1521
f337b084
TH
1522=item Character(s) in '%c' format wrapped in pack
1523
1524(W pack) You tried something like
1525
1526 pack("u", "\x{1f3}b")
1527
1a147d38 1528where the format expects to process a sequence of bytes (character with a
6903afa2 1529value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1530uses the character values modulus 256 instead, as if you had provided:
1531
1532 pack("u", "\x{f3}b")
1533
1534=item Character(s) in '%c' format wrapped in unpack
1535
1536(W unpack) You tried something like
1537
1538 unpack("s", "\x{1f3}b")
1539
1a147d38 1540where the format expects to process a sequence of bytes (character with a
6903afa2 1541value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1542uses the character values modulus 256 instead, as if you had provided:
1543
1544 unpack("s", "\x{f3}b")
1545
f51551f7
FC
1546=item charnames alias definitions may not contain a sequence of multiple spaces
1547
1548(F) You defined a character name which had multiple space characters
1549in a row. Change them to single spaces. Usually these names are
1550defined in the C<:alias> import argument to C<use charnames>, but they
1551could be defined by a translator installed into C<$^H{charnames}>. See
1552L<charnames/CUSTOM ALIASES>.
1553
1554=item charnames alias definitions may not contain trailing white-space
1555
1556(F) You defined a character name which ended in a space
1557character. Remove the trailing space(s). Usually these names are
1558defined in the C<:alias> import argument to C<use charnames>, but they
1559could be defined by a translator installed into C<$^H{charnames}>.
1560See L<charnames/CUSTOM ALIASES>.
1561
6e8a73f2 1562=item \C is deprecated in regex; marked by S<<-- HERE> in m/%s/
f51551f7
FC
1563
1564(D deprecated, regexp) The \C character class is deprecated, and will
1565become a compile-time error in a future release of perl (tentatively
3617dbb6
FC
1566v5.24). This construct allows you to match a single byte of what makes
1567up a multi-byte single UTF8 character, and breaks encapsulation. It is
1568currently also very buggy. If you really need to process the individual
f51551f7
FC
1569bytes, you probably want to convert your string to one where each
1570underlying byte is stored as a character, with utf8::encode().
1571
f866a7cd
FC
1572=item "\c%c" is more clearly written simply as "%s"
1573
1574(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1575non-printable characters. You used it for a printable one, which
1576is better written as simply itself, perhaps preceded by a backslash
1577for non-word characters. Doing it the way you did is not portable
1578between ASCII and EBCDIC platforms.
f866a7cd 1579
6651ba0b
FC
1580=item Cloning substitution context is unimplemented
1581
1582(F) Creating a new thread inside the C<s///> operator is not supported.
1583
abc7ecad
SP
1584=item closedir() attempted on invalid dirhandle %s
1585
1586(W io) The dirhandle you tried to close is either closed or not really
1587a dirhandle. Check your control flow.
1588
5a25739d
FC
1589=item close() on unopened filehandle %s
1590
1591(W unopened) You tried to close a filehandle that was never opened.
1592
541ed3a9
FC
1593=item Closure prototype called
1594
1595(F) If a closure has attributes, the subroutine passed to an attribute
1596handler is the prototype that is cloned when a new closure is created.
1597This subroutine cannot be called.
1598
49704364
LW
1599=item Code missing after '/'
1600
6903afa2
FC
1601(F) You had a (sub-)template that ends with a '/'. There must be
1602another template code following the slash. See L<perlfunc/pack>.
49704364 1603
5a25739d
FC
1604=item Code point 0x%X is not Unicode, may not be portable
1605
2d88a86a 1606(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1607of U+10FFFF.
1608
1609Perl allows strings to contain a superset of Unicode code points, up
1610to the limit of what is storable in an unsigned integer on your system,
1611but these may not be accepted by other languages/systems. At one time,
1612it was legal in some standards to have code points up to 0x7FFF_FFFF,
1613but not higher. Code points above 0xFFFF_FFFF require larger than a
161432 bit word.
0876b9a0 1615
6df41af2
GS
1616=item %s: Command not found
1617
a892b81a 1618(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1619instead of Perl. Check the #! line, or manually feed your script into
1620Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1621
1622 #!/usr/bin/perl -w
6df41af2 1623
7a2e2cd6
PP
1624=item Compilation failed in require
1625
1626(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1627Perl uses this generic message when none of the errors that it
1628encountered were severe enough to halt compilation immediately.
7a2e2cd6 1629
c3464db5
DD
1630=item Complex regular subexpression recursion limit (%d) exceeded
1631
be771a83
GS
1632(W regexp) The regular expression engine uses recursion in complex
1633situations where back-tracking is required. Recursion depth is limited
1634to 32766, or perhaps less in architectures where the stack cannot grow
1635arbitrarily. ("Simple" and "medium" situations are handled without
1636recursion and are not subject to a limit.) Try shortening the string
1637under examination; looping in Perl code (e.g. with C<while>) rather than
1638in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1639that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1640on I<Mastering Regular Expressions>.)
c3464db5 1641
69282e91 1642=item connect() on closed socket %s
a0d0e21e 1643
be771a83
GS
1644(W closed) You tried to do a connect on a closed socket. Did you forget
1645to check the return value of your socket() call? See
1646L<perlfunc/connect>.
a0d0e21e 1647
e21e7c6a
FC
1648=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1649
1650(F) The subroutine registered to handle constant overloading
1651(see L<overload>) or a custom charnames handler (see
1652L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1653
1654=item Constant(%s): $^H{%s} is not defined
1655
1656(F) The parser found inconsistencies while attempting to define an
1657overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1658L<overload> pragma?
e21e7c6a 1659
779c5bc9
GS
1660=item Constant is not %s reference
1661
1662(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1663is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1664The message indicates the type of reference that was expected. This
be771a83 1665usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1666See L<perlsub/"Constant Functions"> and L<constant>.
1667
0ac016fc
FC
1668=item Constants from lexical variables potentially modified elsewhere are
1669deprecated
1670
1671(D deprecated) You wrote something like
1672
1673 my $var;
1674 $sub = sub () { $var };
1675
1676but $var is referenced elsewhere and could be modified after the C<sub>
1677expression is evaluated. Either it is explicitly modified elsewhere
1678(C<$var = 3>) or it is passed to a subroutine or to an operator like
1679C<printf> or C<map>, which may or may not modify the variable.
1680
1681Traditionally, Perl has captured the value of the variable at that
1682point and turned the subroutine into a constant eligible for inlining.
1683In those cases where the variable can be modified elsewhere, this
1684breaks the behavior of closures, in which the subroutine captures
1685the variable itself, rather than its value, so future changes to the
1686variable are reflected in the subroutine's return value.
1687
1688This usage is deprecated, because the behavior is likely to change
1689in a future version of Perl.
1690
1691If you intended for the subroutine to be eligible for inlining, then
1692make sure the variable is not referenced elsewhere, possibly by
1693copying it:
1694
1695 my $var2 = $var;
1696 $sub = sub () { $var2 };
1697
1698If you do want this subroutine to be a closure that reflects future
1699changes to the variable that it closes over, add an explicit C<return>:
1700
1701 my $var;
1702 $sub = sub () { return $var };
1703
4cee8e80
CS
1704=item Constant subroutine %s redefined
1705
aeb94125
FC
1706(W redefine)(S) You redefined a subroutine which had previously
1707been eligible for inlining. See L<perlsub/"Constant Functions">
1708for commentary and workarounds.
4cee8e80 1709
9607fc9c
PP
1710=item Constant subroutine %s undefined
1711
be771a83
GS
1712(W misc) You undefined a subroutine which had previously been eligible
1713for inlining. See L<perlsub/"Constant Functions"> for commentary and
1714workarounds.
9607fc9c 1715
5a25739d
FC
1716=item Constant(%s) unknown
1717
1718(F) The parser found inconsistencies either while attempting
1719to define an overloaded constant, or when trying to find the
1720character name specified in the C<\N{...}> escape. Perhaps you
3ee1a09c 1721forgot to load the corresponding L<overload> pragma?
5a25739d 1722
4a873d7a
FC
1723=item :const is experimental
1724
1725(S experimental::const_attr) The "const" attribute is experimental.
1726If you want to use the feature, disable the warning with C<no warnings
1727'experimental::const_attr'>, but know that in doing so you are taking
1728the risk that your code may break in a future Perl version.
1729
b77472f9
FC
1730=item :const is not permitted on named subroutines
1731
1732(F) The "const" attribute causes an anonymous subroutine to be run and
465068b9 1733its value captured at the time that it is cloned. Named subroutines are
b77472f9
FC
1734not cloned like this, so the attribute does not make sense on them.
1735
e7ea3e70
IZ
1736=item Copy method did not return a reference
1737
6903afa2 1738(F) The method which overloads "=" is buggy. See
13a2d996 1739L<overload/Copy Constructor>.
e7ea3e70 1740
4aaa4757
FC
1741=item &CORE::%s cannot be called directly
1742
1743(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1744with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1745in this package cannot yet be called that way, but must be
1746called as barewords. Something like this will work:
1747
1748 BEGIN { *shove = \&CORE::push; }
1749 shove @array, 1,2,3; # pushes on to @array
1750
6798c92b
GS
1751=item CORE::%s is not a keyword
1752
1753(F) The CORE:: namespace is reserved for Perl keywords.
1754
675fa9ff
FC
1755=item Corrupted regexp opcode %d > %d
1756
1757(P) This is either an error in Perl, or, if you're using
1758one, your L<custom regular expression engine|perlreapi>. If not the
1759latter, report the problem through the L<perlbug> utility.
1760
a0d0e21e
LW
1761=item corrupted regexp pointers
1762
1763(P) The regular expression engine got confused by what the regular
1764expression compiler gave it.
1765
1766=item corrupted regexp program
1767
be771a83
GS
1768(P) The regular expression engine got passed a regexp program without a
1769valid magic number.
a0d0e21e 1770
de42a5a9 1771=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1772
1773(P) The malloc package that comes with Perl had an internal failure.
1774
49704364
LW
1775=item Count after length/code in unpack
1776
1777(F) You had an unpack template indicating a counted-length string, but
1778you have also specified an explicit size for the string. See
1779L<perlfunc/pack>.
1780
f2cccb4c
KW
1781=for comment
1782The following are used in lib/diagnostics.t for testing two =items that
1783share the same description. Changes here need to be propagated to there
1784
6651ba0b
FC
1785=item Deep recursion on anonymous subroutine
1786
a0d0e21e
LW
1787=item Deep recursion on subroutine "%s"
1788
be771a83
GS
1789(W recursion) This subroutine has called itself (directly or indirectly)
1790100 times more than it has returned. This probably indicates an
1791infinite recursion, unless you're writing strange benchmark programs, in
1792which case it indicates something else.
a0d0e21e 1793
aad1d01f
NC
1794This threshold can be changed from 100, by recompiling the F<perl> binary,
1795setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1796
e0e4a6e3
FC
1797=item (?(DEFINE)....) does not allow branches in regex; marked by
1798S<<-- HERE> in m/%s/
bcb95744 1799
6903afa2 1800(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1801most likely cause of this error is that you left out a parenthesis inside
1802of the C<....> part.
1803
6e8a73f2 1804The S<<-- HERE> shows whereabouts in the regular expression the problem was
bcb95744
FC
1805discovered.
1806
62658f4d
PM
1807=item %s defines neither package nor VERSION--version check failed
1808
1809(F) You said something like "use Module 42" but in the Module file
1810there are neither package declarations nor a C<$VERSION>.
1811
36447869
FC
1812=item delete argument is index/value array slice, use array slice
1813
1814(F) You used index/value array slice syntax (C<%array[...]>) as
1815the argument to C<delete>. You probably meant C<@array[...]> with
1816an @ symbol instead.
1817
1818=item delete argument is key/value hash slice, use hash slice
1819
1820(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1821C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1822
0ffcbc25
FC
1823=item delete argument is not a HASH or ARRAY element or slice
1824
4a0af295 1825(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1826such as:
1827
1828 $foo{$bar}
1829 $ref->{"susie"}[12]
1830
1831or a hash or array slice, such as:
1832
1833 @foo[$bar, $baz, $xyzzy]
1834 @{$ref->[12]}{"susie", "queue"}
1835
fc36a67e
PP
1836=item Delimiter for here document is too long
1837
be771a83
GS
1838(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1839long for Perl to handle. You have to be seriously twisted to write code
1840that triggers this error.
fc36a67e 1841
6d3b25aa
RGS
1842=item Deprecated use of my() in false conditional
1843
fa816bf3
FC
1844(D deprecated) You used a declaration similar to C<my $x if 0>. There
1845has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1846not to be cleared at scope exit when its declaration includes a false
6903afa2 1847conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1848static variable. Since we intend to fix this bug, we don't want people
6903afa2 1849relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1850declaring the variable in a separate block outside the function, eg
36fb85f3 1851
6d3b25aa
RGS
1852 sub f { my $x if 0; return $x++ }
1853
1854becomes
1855
1856 { my $x; sub f { return $x++ } }
1857
ea9d9ebc 1858Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1859lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1860
1861 sub f { state $x; return $x++ }
1862
500ab966
RGS
1863=item DESTROY created new reference to dead object '%s'
1864
1865(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1866just being DESTROYed. Perl is confused, and prefers to abort rather
1867than to create a dangling reference.
500ab966 1868
3cdd684c
TP
1869=item Did not produce a valid header
1870
1871See Server error.
1872
6df41af2
GS
1873=item %s did not return a true value
1874
1875(F) A required (or used) file must return a true value to indicate that
1876it compiled correctly and ran its initialization code correctly. It's
1877traditional to end such a file with a "1;", though any true value would
1878do. See L<perlfunc/require>.
1879
cc507455 1880=item (Did you mean &%s instead?)
4633a7c4 1881
413ff9f6
FC
1882(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1883some such.
4633a7c4 1884
cc507455 1885=item (Did you mean "local" instead of "our"?)
33633739 1886
be771a83
GS
1887(W misc) Remember that "our" does not localize the declared global
1888variable. You have declared it again in the same lexical scope, which
1889seems superfluous.
33633739 1890
cc507455 1891=item (Did you mean $ or @ instead of %?)
a0d0e21e 1892
be771a83
GS
1893(W) You probably said %hash{$key} when you meant $hash{$key} or
1894@hash{@keys}. On the other hand, maybe you just meant %hash and got
1895carried away.
748a9306 1896
7e1af8bc 1897=item Died
5f05dabc
PP
1898
1899(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1900you called it with no args and C<$@> was empty.
5f05dabc 1901
3cdd684c
TP
1902=item Document contains no data
1903
1904See Server error.
1905
62658f4d
PM
1906=item %s does not define %s::VERSION--version check failed
1907
1908(F) You said something like "use Module 42" but the Module did not
943fc58e 1909define a C<$VERSION>.
62658f4d 1910
49704364
LW
1911=item '/' does not take a repeat count
1912
1913(F) You cannot put a repeat count of any kind right after the '/' code.
1914See L<perlfunc/pack>.
1915
95cb0d72
FC
1916=item Don't know how to get file name
1917
1918(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1919somehow called on another platform. This should not happen.
1920
4021c788 1921=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1922
1923(P) The internal handling of magical variables has been cursed.
1924
1925=item do_study: out of memory
1926
1927(P) This should have been caught by safemalloc() instead.
1928
6df41af2
GS
1929=item (Do you need to predeclare %s?)
1930
56da5a46
RGS
1931(S syntax) This is an educated guess made in conjunction with the message
1932"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1933name is being referenced that hasn't been declared yet. This may be
1934because of ordering problems in your file, or because of a missing
be771a83
GS
1935"sub", "package", "require", or "use" statement. If you're referencing
1936something that isn't defined yet, you don't actually have to define the
1937subroutine or package before the current location. You can use an empty
1938"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1939
ac206dc8
RGS
1940=item dump() better written as CORE::dump()
1941
1942(W misc) You used the obsolescent C<dump()> built-in function, without fully
1943qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1944
84d78eb7
YO
1945=item dump is not supported
1946
1947(F) Your machine doesn't support dump/undump.
1948
a0d0e21e
LW
1949=item Duplicate free() ignored
1950
be771a83
GS
1951(S malloc) An internal routine called free() on something that had
1952already been freed.
a0d0e21e 1953
1109a392
MHM
1954=item Duplicate modifier '%c' after '%c' in %s
1955
35f0cd76
FC
1956(W unpack) You have applied the same modifier more than once after a
1957type in a pack template. See L<perlfunc/pack>.
1109a392 1958
0953b66b
FC
1959=item each on reference is experimental
1960
0773cb3e
FC
1961(S experimental::autoderef) C<each> with a scalar argument is experimental
1962and may change or be removed in a future Perl version. If you want to
1963take the risk of using this feature, simply disable this warning:
0953b66b 1964
d401967c 1965 no warnings "experimental::autoderef";
0953b66b 1966
4633a7c4
LW
1967=item elseif should be elsif
1968
fa816bf3
FC
1969(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1970it's ugly. Your code will be interpreted as an attempt to call a method
1971named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1972unlikely to be what you want.
1973
e0e4a6e3 1974=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1975
af6f566e 1976(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1977described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1978a regular expression without specifying the property name.
ab13f0c7 1979
85ab1d1d 1980=item entering effective %s failed
5ff3f7a4 1981
85ab1d1d 1982(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1983effective uids or gids failed.
1984
c038024b
RGS
1985=item %ENV is aliased to %s
1986
1987(F) You're running under taint mode, and the C<%ENV> variable has been
1988aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1989program's environment. This is potentially insecure.
c038024b 1990
748a9306
LW
1991=item Error converting file specification %s
1992
5f05dabc 1993(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1994specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1995single form when it must operate on them directly. Either you've passed
1996an invalid file specification to Perl, or you've found a case the
1997conversion routines don't handle. Drat.
748a9306 1998
ad19ef22 1999=item Eval-group in insecure regular expression
e4d48cc9 2000
be771a83
GS
2001(F) Perl detected tainted data when trying to compile a regular
2002expression that contains the C<(?{ ... })> zero-width assertion, which
2003is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 2004
ad19ef22 2005=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 2006
be771a83
GS
2007(F) Perl tried to compile a regular expression containing the
2008C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
2009pattern contains interpolated values. Since that is a security risk,
2010it is not allowed. If you insist, you may still do this by using the
2011C<re 'eval'> pragma or by explicitly building the pattern from an
2012interpolated string at run time and using that in an eval(). See
2013L<perlre/(?{ code })>.
e4d48cc9 2014
ad19ef22 2015=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 2016
be771a83
GS
2017(F) A regular expression contained the C<(?{ ... })> zero-width
2018assertion, but that construct is only allowed when the C<use re 'eval'>
2019pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 2020
e0e4a6e3
FC
2021=item EVAL without pos change exceeded limit in regex; marked by
2022S<<-- HERE> in m/%s/
1a147d38
YO
2023
2024(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 2025any text. Restructure the pattern so that text is consumed.
1a147d38 2026
6e8a73f2 2027The S<<-- HERE> shows whereabouts in the regular expression the problem was
1a147d38
YO
2028discovered.
2029
fc36a67e
PP
2030=item Excessively long <> operator
2031
2032(F) The contents of a <> operator may not exceed the maximum size of a
2033Perl identifier. If you're just trying to glob a long list of
2034filenames, try using the glob() operator, or put the filenames into a
2035variable and glob that.
2036
ed9aa3b7
SG
2037=item exec? I'm not *that* kind of operating system
2038
af8bb25a 2039(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 2040OS. See L<perlport>.
ed9aa3b7 2041
fe13d51d 2042=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
2043
2044(F) The final summary message when a Perl compilation fails.
2045
0ffcbc25
FC
2046=item exists argument is not a HASH or ARRAY element or a subroutine
2047
4a0af295 2048(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
2049subroutine with an ampersand, such as:
2050
2051 $foo{$bar}
2052 $ref->{"susie"}[12]
2053 &do_something
2054
2055=item exists argument is not a subroutine name
2056
ccfc2567
FC
2057(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
2058and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 2059
a0d0e21e
LW
2060=item Exiting eval via %s
2061
be771a83
GS
2062(W exiting) You are exiting an eval by unconventional means, such as a
2063goto, or a loop control statement.
e476b1b5
GS
2064
2065=item Exiting format via %s
2066
9a2ff54b 2067(W exiting) You are exiting a format by unconventional means, such as a
be771a83 2068goto, or a loop control statement.
a0d0e21e 2069
0a753a76
PP
2070=item Exiting pseudo-block via %s
2071
be771a83
GS
2072(W exiting) You are exiting a rather special block construct (like a
2073sort block or subroutine) by unconventional means, such as a goto, or a
2074loop control statement. See L<perlfunc/sort>.
0a753a76 2075
a0d0e21e
LW
2076=item Exiting subroutine via %s
2077
be771a83
GS
2078(W exiting) You are exiting a subroutine by unconventional means, such
2079as a goto, or a loop control statement.
a0d0e21e
LW
2080
2081=item Exiting substitution via %s
2082
be771a83
GS
2083(W exiting) You are exiting a substitution by unconventional means, such
2084as a return, a goto, or a loop control statement.
a0d0e21e 2085
e0e4a6e3 2086=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 2087
675fa9ff 2088(F) You wrote something like
c608e803
KW
2089
2090 (?13
2091
2092to denote a capturing group of the form
2093L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
2094but omitted the C<")">.
2095
e0e4a6e3 2096=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 2097
8b6fbf55
FC
2098(F) The C<(?[...])> extended character class regular expression construct
2099only allows character classes (including character class escapes like
2100C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
2101containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
2102This allows a regular expression containing just C<(?[...])> to be
2103interpolated. If you see this error message, then you probably
2104have some other C<(?...)> construct inside your character class. See
2105L<perlrecharclass/Extended Bracketed Character Classes>.
2106
baabe3fb 2107=item Experimental aliasing via reference not enabled
1f8155a2 2108
baabe3fb 2109(F) To do aliasing via references, you must first enable the feature:
1f8155a2 2110
baabe3fb
FC
2111 no warnings "experimental::refaliasing";
2112 use feature "refaliasing";
1f8155a2
FC
2113 \$x = \$y;
2114
30d9c59b
Z
2115=item Experimental subroutine signatures not enabled
2116
2117(F) To use subroutine signatures, you must first enable them:
2118
caa35032 2119 no warnings "experimental::signatures";
30d9c59b
Z
2120 use feature "signatures";
2121 sub foo ($left, $right) { ... }
2122
6da34ecb
FC
2123=item Experimental "%s" subs not enabled
2124
2125(F) To use lexical subs, you must first enable them:
2126
2127 no warnings 'experimental::lexical_subs';
2128 use feature 'lexical_subs';
2129 my sub foo { ... }
2130
7b8d334a
GS
2131=item Explicit blessing to '' (assuming package main)
2132
be771a83
GS
2133(W misc) You are blessing a reference to a zero length string. This has
2134the effect of blessing the reference into the package main. This is
2135usually not what you want. Consider providing a default target package,
2136e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2137
6df41af2
GS
2138=item %s: Expression syntax
2139
be771a83
GS
2140(A) You've accidentally run your script through B<csh> instead of Perl.
2141Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2142
2143=item %s failed--call queue aborted
2144
3c10abe3
AG
2145(F) An untrapped exception was raised while executing a UNITCHECK,
2146CHECK, INIT, or END subroutine. Processing of the remainder of the
2147queue of such routines has been prematurely ended.
6df41af2 2148
e0e4a6e3 2149=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2150
98d31c73 2151(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2152character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2153in your false range is interpreted as a literal "-". In a C<(?[...])>
2154construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2155the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2156the problem was discovered. See L<perlre>.
73b437c8 2157
1b1ee2ef 2158=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2159
be771a83
GS
2160(P) An error peculiar to VMS. Something untoward happened in a VMS
2161system service or RTL routine; Perl's exit status should provide more
2162details. The filename in "at %s" and the line number in "line %d" tell
2163you which section of the Perl source code is distressed.
a0d0e21e
LW
2164
2165=item fcntl is not implemented
2166
2167(F) Your machine apparently doesn't implement fcntl(). What is this, a
2168PDP-11 or something?
2169
22846ab4
AB
2170=item FETCHSIZE returned a negative value
2171
2172(F) A tied array claimed to have a negative number of elements, which
2173is not possible.
2174
f337b084
TH
2175=item Field too wide in 'u' format in pack
2176
d8b5cc61 2177(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2178which can't encode values above 63. So there is no point in asking for
2179a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2180C<u63> as the format.
f337b084 2181
af8c498a 2182=item Filehandle %s opened only for input
a0d0e21e 2183
6c8d78fb
HS
2184(W io) You tried to write on a read-only filehandle. If you intended
2185it to be a read-write filehandle, you needed to open it with "+<" or
2186"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2187write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2188
af8c498a 2189=item Filehandle %s opened only for output
a0d0e21e 2190
6c8d78fb
HS
2191(W io) You tried to read from a filehandle opened only for writing, If
2192you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2193with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2194read from the file, use "<". See L<perlfunc/open>. Another possibility
2195is that you attempted to open filedescriptor 0 (also known as STDIN) for
2196output (maybe you closed STDIN earlier?).
97828cef
RGS
2197
2198=item Filehandle %s reopened as %s only for input
2199
2200(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2201as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2202previously.
2203
2204=item Filehandle STDIN reopened as %s only for output
2205
2206(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2207as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2208
2209=item Final $ should be \$ or $name
2210
2211(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2212a literal dollar sign, or was meant to introduce a variable name that
2213happens to be missing. So you have to put either the backslash or the
2214name.
a0d0e21e 2215
56e90b21
GS
2216=item flock() on closed filehandle %s
2217
be771a83 2218(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2219some time before now. Check your control flow. flock() operates on
be771a83
GS
2220filehandles. Are you attempting to call flock() on a dirhandle by the
2221same name?
56e90b21 2222
6df41af2
GS
2223=item Format not terminated
2224
2225(F) A format must be terminated by a line with a solitary dot. Perl got
2226to the end of your file without finding such a line.
2227
a0d0e21e
LW
2228=item Format %s redefined
2229
e476b1b5 2230(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2231
2232 {
271595cc 2233 no warnings 'redefine';
a0d0e21e
LW
2234 eval "format NAME =...";
2235 }
2236
a0d0e21e
LW
2237=item Found = in conditional, should be ==
2238
e476b1b5 2239(W syntax) You said
a0d0e21e
LW
2240
2241 if ($foo = 123)
2242
2243when you meant
2244
2245 if ($foo == 123)
2246
2247(or something like that).
2248
6df41af2
GS
2249=item %s found where operator expected
2250
56da5a46
RGS
2251(S syntax) The Perl lexer knows whether to expect a term or an operator.
2252If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2253operator, it gives you this warning. Usually it indicates that an
2254operator or delimiter was omitted, such as a semicolon.
6df41af2 2255
a0d0e21e
LW
2256=item gdbm store returned %d, errno %d, key "%s"
2257
2258(S) A warning from the GDBM_File extension that a store failed.
2259
2260=item gethostent not implemented
2261
2262(F) Your C library apparently doesn't implement gethostent(), probably
2263because if it did, it'd feel morally obligated to return every hostname
2264on the Internet.
2265
69282e91 2266=item get%sname() on closed socket %s
a0d0e21e 2267
be771a83
GS
2268(W closed) You tried to get a socket or peer socket name on a closed
2269socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2270
748a9306
LW
2271=item getpwnam returned invalid UIC %#o for user "%s"
2272
2273(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2274C<getpwnam> operator returned an invalid UIC.
2275
6df41af2
GS
2276=item getsockopt() on closed socket %s
2277
be771a83
GS
2278(W closed) You tried to get a socket option on a closed socket. Did you
2279forget to check the return value of your socket() call? See
6df41af2
GS
2280L<perlfunc/getsockopt>.
2281
0f539b13
BF
2282=item given is experimental
2283
675fa9ff
FC
2284(S experimental::smartmatch) C<given> depends on smartmatch, which
2285is experimental, so its behavior may change or even be removed
2286in any future release of perl. See the explanation under
2287L<perlsyn/Experimental Details on given and when>.
0f539b13 2288
68567d27
FC
2289=item Global symbol "%s" requires explicit package name (did you forget to
2290declare "my %s"?)
6df41af2 2291
a4edf47d 2292(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2293that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2294declared beforehand using "our", or explicitly qualified to say
2295which package the global variable is in (using "::").
6df41af2 2296
e476b1b5
GS
2297=item glob failed (%s)
2298
5ead438e 2299(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2300for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2301pattern that caused the external program to fail and exit with a
be771a83 2302nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2303resulted in a coredump, this may also mean that your csh (C shell)
2304is broken. If so, you should change all of the csh-related variables
2305in config.sh: If you have tcsh, make the variables refer to it as
2306if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2307all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2308think csh is missing. In either case, after editing config.sh, run
75b44862 2309C<./Configure -S> and rebuild Perl.
e476b1b5 2310
a0d0e21e
LW
2311=item Glob not terminated
2312
2313(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2314a term, so it's looking for the corresponding right angle bracket, and
2315not finding it. Chances are you left some needed parentheses out
2316earlier in the line, and you really meant a "less than".
a0d0e21e 2317
b35b96b6
JH
2318=item gmtime(%f) failed
2319
2320(W overflow) You called C<gmtime> with a number that it could not handle:
2321too large, too small, or NaN. The returned value is C<undef>.
2322
bcd05b94 2323=item gmtime(%f) too large
8b56d6ff 2324
e9200be3 2325(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2326it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2327date. This warning is also triggered with NaN (the special
fc003d4b
MS
2328not-a-number value).
2329
bcd05b94 2330=item gmtime(%f) too small
fc003d4b 2331
e9200be3 2332(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2333it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2334
6df41af2 2335=item Got an error from DosAllocMem
a0d0e21e 2336
6df41af2
GS
2337(P) An error peculiar to OS/2. Most probably you're using an obsolete
2338version of Perl, and this should not happen anyway.
a0d0e21e
LW
2339
2340=item goto must have label
2341
2342(F) Unlike with "next" or "last", you're not allowed to goto an
2343unspecified destination. See L<perlfunc/goto>.
2344
6651ba0b
FC
2345=item Goto undefined subroutine%s
2346
2347(F) You tried to call a subroutine with C<goto &sub> syntax, but
2348the indicated subroutine hasn't been defined, or if it was, it
2349has since been undefined.
2350
6fbc9859 2351=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2352S<<-- HERE> in m/%s/
1f4f6bf1
YO
2353
2354(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2355they must start with a non-digit word character. A common cause of
2356this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2357
5a25739d
FC
2358=item ()-group starts with a count
2359
2360(F) A ()-group started with a count. A count is supposed to follow
2361something: a template character or a ()-group. See L<perlfunc/pack>.
2362
fe13d51d 2363=item %s had compilation errors.
6df41af2
GS
2364
2365(F) The final summary message when a C<perl -c> fails.
2366
a0d0e21e
LW
2367=item Had to create %s unexpectedly
2368
be771a83
GS
2369(S internal) A routine asked for a symbol from a symbol table that ought
2370to have existed already, but for some reason it didn't, and had to be
2371created on an emergency basis to prevent a core dump.
a0d0e21e 2372
6df41af2
GS
2373=item %s has too many errors
2374
2375(F) The parser has given up trying to parse the program after 10 errors.
2376Further error messages would likely be uninformative.
2377
cc4d09e1
KW
2378=item Having more than one /%c regexp modifier is deprecated
2379
2380(D deprecated, regexp) You used the indicated regular expression pattern
2381modifier at least twice in a string of modifiers. It is deprecated to
2382do this with this particular modifier, to allow future extensions to the
2383Perl language.
2384
61e61fbc
JH
2385=item Hexadecimal float: exponent overflow
2386
d8f2b442 2387(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2388than the floating point supports.
2389
2390=item Hexadecimal float: exponent underflow
2391
d8f2b442 2392(W overflow) The hexadecimal floating point has a smaller exponent
61e61fbc
JH
2393than the floating point supports.
2394
cf4f6003
JH
2395=item Hexadecimal float: internal error
2396
2397(F) Something went horribly bad in hexadecimal float handling.
2398
61e61fbc
JH
2399=item Hexadecimal float: mantissa overflow
2400
2401(W overflow) The hexadecimal floating point literal had more bits in
2402the mantissa (the part between the 0x and the exponent, also known as
2403the fraction or the significand) than the floating point supports.
2404
40bca5ae
JH
2405=item Hexadecimal float: precision loss
2406
2407(W overflow) The hexadecimal floating point had internally more
2408digits than could be output. This can be caused by unsupported
2409long double formats, or by 64-bit integers not being available
2410(needed to retrieve the digits under some configurations).
2411
2412=item Hexadecimal float: unsupported long double format
2413
2414(F) You have configured Perl to use long doubles but
d8f2b442 2415the internals of the long double format are unknown;
40bca5ae
JH
2416therefore the hexadecimal float output is impossible.
2417
252aa082
JH
2418=item Hexadecimal number > 0xffffffff non-portable
2419
e476b1b5 2420(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2421(4294967295) and therefore non-portable between systems. See
2422L<perlport> for more on portability concerns.
252aa082 2423
8903cb82
PP
2424=item Identifier too long
2425
2426(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2427about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2428names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2429of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2430
e0e4a6e3
FC
2431=item Ignoring zero length \N{} in character class in regex; marked by
2432S<<-- HERE> in m/%s/
fc8cd66c 2433
f3ba6905 2434(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
0f44b2a5
FC
2435zero-length sequence. When such an escape is used in a character
2436class its behavior is not well defined. Check that the correct
2437escape has been used, and the correct charname handler is in scope.
fc8cd66c 2438
6df41af2 2439=item Illegal binary digit %s
f675dbe5 2440
6df41af2 2441(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2442
6df41af2 2443=item Illegal binary digit %s ignored
a0d0e21e 2444
be771a83
GS
2445(W digit) You may have tried to use a digit other than 0 or 1 in a
2446binary number. Interpretation of the binary number stopped before the
2447offending digit.
a0d0e21e 2448
6597eb22
FC
2449=item Illegal character after '_' in prototype for %s : %s
2450
e4d150f1
FC
2451(W illegalproto) An illegal character was found in a prototype
2452declaration. The '_' in a prototype must be followed by a ';',
2453indicating the rest of the parameters are optional, or one of '@'
2454or '%', since those two will accept 0 or more final parameters.
6597eb22 2455
78d0fecf 2456=item Illegal character \%o (carriage return)
4fdae800 2457
d5898338 2458(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2459would any other whitespace, which means you should never see this error
2460when Perl was built using standard options. For some reason, your
2461version of Perl appears to have been built without this support. Talk
2462to your Perl administrator.
4fdae800 2463
d37a9538
ST
2464=item Illegal character in prototype for %s : %s
2465
197afce1 2466(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2467Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2468Perhaps you were trying to write a subroutine signature but didn't enable
2469that feature first (C<use feature 'signatures'>), so your signature was
2470instead interpreted as a bad prototype.
d37a9538 2471
904d85c5
RGS
2472=item Illegal declaration of anonymous subroutine
2473
2474(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2475you must always specify a block of code. See L<perlsub>.
904d85c5 2476
8e742a20
MHM
2477=item Illegal declaration of subroutine %s
2478
6903afa2 2479(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2480
a0d0e21e
LW
2481=item Illegal division by zero
2482
be771a83
GS
2483(F) You tried to divide a number by 0. Either something was wrong in
2484your logic, or you need to put a conditional in to guard against
2485meaningless input.
a0d0e21e 2486
6df41af2
GS
2487=item Illegal hexadecimal digit %s ignored
2488
be771a83
GS
2489(W digit) You may have tried to use a character other than 0 - 9 or
2490A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2491number stopped before the illegal character.
6df41af2 2492
a0d0e21e
LW
2493=item Illegal modulus zero
2494
be771a83
GS
2495(F) You tried to divide a number by 0 to get the remainder. Most
2496numbers don't take to this kindly.
a0d0e21e 2497
6df41af2 2498=item Illegal number of bits in vec
399388f4 2499
6df41af2
GS
2500(F) The number of bits in vec() (the third argument) must be a power of
2501two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2502
2503=item Illegal octal digit %s
a0d0e21e 2504
d1be9408 2505(F) You used an 8 or 9 in an octal number.
a0d0e21e 2506
399388f4 2507=item Illegal octal digit %s ignored
748a9306 2508
d1be9408 2509(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2510Interpretation of the octal number stopped before the 8 or 9.
748a9306 2511
e0e4a6e3 2512=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2513
675fa9ff 2514(F) You wrote something like
c608e803
KW
2515
2516 (?+foo)
2517
2518The C<"+"> is valid only when followed by digits, indicating a
2519capturing group. See
2520L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2521
375ed12a
JH
2522=item Illegal suidscript
2523
2524(F) The script run under suidperl was somehow illegal.
2525
fe13d51d 2526=item Illegal switch in PERL5OPT: -%c
6ff81951 2527
6df41af2 2528(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2529following switches: B<-[CDIMUdmtw]>.
6ff81951 2530
6df41af2 2531=item Ill-formed CRTL environ value "%s"
81e118e0 2532
75b44862 2533(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2534internal environ array, and encountered an element without the C<=>
2535delimiter used to separate keys from values. The element is ignored.
09bef843 2536
6df41af2 2537=item Ill-formed message in prime_env_iter: |%s|
54310121 2538
be771a83
GS
2539(W internal) A warning peculiar to VMS. Perl tried to read a logical
2540name or CLI symbol definition when preparing to iterate over %ENV, and
2541didn't see the expected delimiter between key and value, so the line was
2542ignored.
54310121 2543
6df41af2 2544=item (in cleanup) %s
9607fc9c 2545
be771a83
GS
2546(W misc) This prefix usually indicates that a DESTROY() method raised
2547the indicated exception. Since destructors are usually called by the
2548system at arbitrary points during execution, and often a vast number of
2549times, the warning is issued only once for any number of failures that
2550would otherwise result in the same message being repeated.
6df41af2 2551
be771a83
GS
2552Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2553also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2554
e0e4a6e3
FC
2555=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2556in m/%s/
0d0b4b3b 2557
675fa9ff 2558(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2559expression inside the construct was completely empty, or if there are
2560too many or few operands for the number of operators. Perl is not smart
2561enough to give you a more precise indication as to what is wrong.
2562
6fbc9859
MH
2563=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2564parent '%s'
2c7d6b9c
RGS
2565
2566(F) The method resolution order (MRO) of the given class is not
2567C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2568documentation in L<mro> for more information.
2569
979699d9
JH
2570=item In EBCDIC the v-string components cannot exceed 2147483647
2571
2572(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2573Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2574encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2575
6a2ed79a 2576=item Infinite recursion in regex
1a147d38
YO
2577
2578(F) You used a pattern that references itself without consuming any input
6903afa2 2579text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2580either consume text or fail.
2581
6dbe9451
NC
2582=item Initialization of state variables in list context currently forbidden
2583
6903afa2
FC
2584(F) Currently the implementation of "state" only permits the
2585initialization of scalar variables in scalar context. Re-write
2586C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2587context. Constructions such as C<state (@a) = foo()> will be
2588supported in a future perl release.
6dbe9451 2589
2186f873
FC
2590=item %%s[%s] in scalar context better written as $%s[%s]
2591
2592(W syntax) In scalar context, you've used an array index/value slice
2593(indicated by %) to select a single element of an array. Generally
2594it's better to ask for a scalar value (indicated by $). The difference
2595is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2596returns and when evaluating its argument, while C<%foo[&bar]> provides
2597a list context to its subscript, which can do weird things if you're
2598expecting only one subscript. When called in list context, it also
2599returns the index (what C<&bar> returns) in addition to the value.
2600
2601=item %%s{%s} in scalar context better written as $%s{%s}
2602
2603(W syntax) In scalar context, you've used a hash key/value slice
2604(indicated by %) to select a single element of a hash. Generally it's
2605better to ask for a scalar value (indicated by $). The difference
2606is that C<$foo{&bar}> always behaves like a scalar, both in the value
2607it returns and when evaluating its argument, while C<@foo{&bar}> and
2608provides a list context to its subscript, which can do weird things
2609if you're expecting only one subscript. When called in list context,
2610it also returns the key in addition to the value.
2611
a0d0e21e
LW
2612=item Insecure dependency in %s
2613
8b1a09fc 2614(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2615The tainting mechanism is turned on when you're running setuid or
2616setgid, or when you specify B<-T> to turn it on explicitly. The
2617tainting mechanism labels all data that's derived directly or indirectly
2618from the user, who is considered to be unworthy of your trust. If any
2619such data is used in a "dangerous" operation, you get this error. See
2620L<perlsec> for more information.
a0d0e21e
LW
2621
2622=item Insecure directory in %s
2623
be771a83
GS
2624(F) You can't use system(), exec(), or a piped open in a setuid or
2625setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2626the world. Also, the PATH must not contain any relative directory.
2627See L<perlsec>.
a0d0e21e 2628
62f468fc 2629=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2630
2631(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2632setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2633C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2634supplied (or potentially supplied) by the user. The script must set
2635the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2636
0e9be77f
DM
2637=item Insecure user-defined property %s
2638
2639(F) Perl detected tainted data when trying to compile a regular
2640expression that contains a call to a user-defined character property
2641function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2642See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2643
b9ef414d
FC
2644=item Integer overflow in format string for %s
2645
2646(F) The indexes and widths specified in the format string of C<printf()>
2647or C<sprintf()> are too large. The numbers must not overflow the size of
2648integers for your architecture.
2649
a7ae9550
GS
2650=item Integer overflow in %s number
2651
35928bc5 2652(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2653either as a literal or as an argument to hex() or oct() is too big for
2654your architecture, and has been converted to a floating point number.
2655On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2656representable without overflow is 0xFFFFFFFF, 037777777777, or
26570b11111111111111111111111111111111 respectively. Note that Perl
2658transparently promotes all numbers to a floating point representation
2659internally--subject to loss of precision errors in subsequent
2660operations.
bbce6d69 2661
fc89ca81
FC
2662=item Integer overflow in srand
2663
2664(S overflow) The number you have passed to srand is too big to fit
2665in your architecture's integer representation. The number has been
2666replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2667architectures). This means you may be getting less randomness than
2668you expect, because different random seeds above the maximum will
2669return the same sequence of random numbers.
2670
46314c13
JP
2671=item Integer overflow in version
2672
18da5252
FC
2673=item Integer overflow in version %d
2674
784d71ed
FC
2675(W overflow) Some portion of a version initialization is too large for
2676the size of integers for your architecture. This is not a warning
f084e84f 2677because there is no rational reason for a version to try and use an
784d71ed
FC
2678element larger than typically 2**32. This is usually caused by trying
2679to use some odd mathematical operation as a version, like 100/9.
46314c13 2680
e0e4a6e3 2681=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2682
2683(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2684The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2685discovered.
2686
748a9306
LW
2687=item Internal inconsistency in tracking vforks
2688
be771a83
GS
2689(S) A warning peculiar to VMS. Perl keeps track of the number of times
2690you've called C<fork> and C<exec>, to determine whether the current call
2691to C<exec> should affect the current script or a subprocess (see
2692L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2693Perl is making a guess and treating this C<exec> as a request to
2694terminate the Perl script and execute the specified command.
748a9306 2695
870978ae
FC
2696=item internal %<num>p might conflict with future printf extensions
2697
2698(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2699formatting follows a slightly different set of rules when called from
2700C or XS code. Specifically, formats consisting of digits followed
2701by "p" (e.g., "%7p") are reserved for future use. If you see this
2702message, then an XS module tried to call that routine with one such
2703reserved format.
2704
e0e4a6e3 2705=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2706
fa816bf3 2707(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2708S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2709discovered.
a0d0e21e 2710
6df41af2
GS
2711=item %s (...) interpreted as function
2712
75b44862 2713(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2714followed by parentheses turns into a function, with all the list
64977eb6 2715operators arguments found inside the parentheses. See
13a2d996 2716L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2717
f51551f7
FC
2718=item In '(?...)', the '(' and '?' must be adjacent in regex;
2719marked by S<<-- HERE> in m/%s/
2720
2721(F) The two-character sequence C<"(?"> in this context in a regular
2722expression pattern should be an indivisible token, with nothing
2723intervening between the C<"("> and the C<"?">, but you separated them
2724with whitespace.
2725
09bef843
SB
2726=item Invalid %s attribute: %s
2727
a4a4c9e2 2728(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2729by Perl or by a user-supplied handler. See L<attributes>.
2730
2731=item Invalid %s attributes: %s
2732
a4a4c9e2 2733(F) The indicated attributes for a subroutine or variable were not
be771a83 2734recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2735
e0e4a6e3
FC
2736=item Invalid character in charnames alias definition; marked by
2737S<<-- HERE> in '%s
225fb84f
KW
2738
2739(F) You tried to create a custom alias for a character name, with
2740the C<:alias> option to C<use charnames> and the specified character in
2741the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2742
c8028aa6
TC
2743=item Invalid \0 character in %s for %s: %s\0%s
2744
fa3234e3
FC
2745(W syscalls) Embedded \0 characters in pathnames or other system call
2746arguments produce a warning as of 5.20. The parts after the \0 were
2747formerly ignored by system calls.
c8028aa6 2748
e0e4a6e3 2749=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2750
2751(F) Only certain characters are valid for character names. The
2752indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2753
c635e13b
PP
2754=item Invalid conversion in %s: "%s"
2755
be771a83
GS
2756(W printf) Perl does not understand the given format conversion. See
2757L<perlfunc/sprintf>.
c635e13b 2758
e0e4a6e3
FC
2759=item Invalid escape in the specified encoding in regex; marked by
2760S<<-- HERE> in m/%s/
9e08bc66 2761
98d31c73 2762(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2763didn't correspond to a single character through the conversion
2764from the encoding specified by the encoding pragma.
98d31c73
FC
2765The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2766instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2767The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2768escape was discovered.
2769
8149aa9f
FC
2770=item Invalid hexadecimal number in \N{U+...}
2771
e0e4a6e3
FC
2772=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2773S<<-- HERE> in m/%s/
aec0ef10 2774
8149aa9f 2775(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2776number. Either it is empty, or you tried to use a character other than
27770 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2778
6651ba0b
FC
2779=item Invalid module name %s with -%c option: contains single ':'
2780
2781(F) The module argument to perl's B<-m> and B<-M> command-line options
2782cannot contain single colons in the module name, but only in the
2783arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2784B<-MFoo:Bar=baz> is not.
2785
2c7d6b9c
RGS
2786=item Invalid mro name: '%s'
2787
162a3e34
FC
2788(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2789where C<foo> is not a valid method resolution order (MRO). Currently,
2790the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2791a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2792
40e4140b
FC
2793=item Invalid negative number (%s) in chr
2794
2795(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2796not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2797character (U+FFFD).
2798
6651ba0b
FC
2799=item invalid option -D%c, use -D'' to see choices
2800
8ff21bfe
FC
2801(S debugging) Perl was called with invalid debugger flags. Call perl
2802with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2803See also L<perlrun/-Dletters>.
6651ba0b 2804
6e8a73f2 2805=item Invalid quantifier in {,} in regex; marked by S<<-- HERE> in m/%s/
35cd12d1
HS
2806
2807(F) The pattern looks like a {min,max} quantifier, but the min or max
2808could not be parsed as a valid number - either it has leading zeroes,
2809or it represents too big a number to cope with. The S<<-- HERE> shows
2810where in the regular expression the problem was discovered. See L<perlre>.
2811
e0e4a6e3 2812=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2813
2814(F) The range specified in a character class had a minimum character
7253e4e3
RK
2815greater than the maximum character. One possibility is that you forgot the
2816C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2817up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2818problem was discovered. See L<perlre>.
6df41af2 2819
d1573ac7 2820=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2821
2822(F) The range specified in the tr/// or y/// operator had a minimum
2823character greater than the maximum character. See L<perlop>.
2824
09bef843
SB
2825=item Invalid separator character %s in attribute list
2826
0120eecf 2827(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2828elements of an attribute list. If the previous attribute had a
2829parenthesised parameter list, perhaps that list was terminated too soon.
2830See L<attributes>.
09bef843 2831
b4581f09
JH
2832=item Invalid separator character %s in PerlIO layer specification %s
2833
2bfc5f71
FC
2834(W layer) When pushing layers onto the Perl I/O system, something other
2835than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2836If the previous attribute had a parenthesised parameter list, perhaps that
2837list was terminated too soon.
2838
2c86d456
DG
2839=item Invalid strict version format (%s)
2840
fa816bf3 2841(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2842A "strict" version number is a positive decimal number (integer or
2843decimal-fraction) without exponentiation or else a dotted-decimal
2844v-string with a leading 'v' character and at least three components.
a6485a24 2845The parenthesized text indicates which criteria were not met.
2c86d456
DG
2846See the L<version> module for more details on allowed version formats.
2847
49704364 2848=item Invalid type '%s' in %s
96e4d5b1 2849
49704364
LW
2850(F) The given character is not a valid pack or unpack type.
2851See L<perlfunc/pack>.
6728c851 2852
49704364 2853(W) The given character is not a valid pack or unpack type but used to be
75b44862 2854silently ignored.
96e4d5b1 2855
2c86d456
DG
2856=item Invalid version format (%s)
2857
fa816bf3 2858(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2859A "lax" version number is a positive decimal number (integer or
2860decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2861v-string. If the v-string has fewer than three components, it
2862must have a leading 'v' character. Otherwise, the leading 'v' is
2863optional. Both decimal and dotted-decimal versions may have a
2864trailing "alpha" component separated by an underscore character
2865after a fractional or dotted-decimal component. The parenthesized
2866text indicates which criteria were not met. See the L<version> module
2867for more details on allowed version formats.
46314c13 2868
798ae1b7
DG
2869=item Invalid version object
2870
fa816bf3
FC
2871(F) The internal structure of the version object was invalid.
2872Perhaps the internals were modified directly in some way or
2873an arbitrary reference was blessed into the "version" class.
798ae1b7 2874
cd209d9d 2875=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2876marked by S<<-- HERE> in m/%s/
675fa9ff 2877
cd209d9d 2878(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2879this context in a regular expression pattern should be an
2880indivisible token, with nothing intervening between the C<"(">
cd209d9d 2881and the C<"*">, but you separated them.
675fa9ff 2882
a0d0e21e
LW
2883=item ioctl is not implemented
2884
2885(F) Your machine apparently doesn't implement ioctl(), which is pretty
2886strange for a machine that supports C.
2887
c289d2f7
JH
2888=item ioctl() on unopened %s
2889
2890(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2891Check your control flow and number of arguments.
c289d2f7 2892
fe13d51d 2893=item IO layers (like '%s') unavailable
363c40c4
SB
2894
2895(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2896you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2897with 'useperlio'.
2898
80cbd5ad
JH
2899=item IO::Socket::atmark not implemented on this architecture
2900
2901(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2902neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2903
6e8a73f2 2904=item '%s' is an unknown bound type in regex; marked by S<<-- HERE> in m/%s/
64935bc6
KW
2905
2906(F) You used C<\b{...}> or C<\B{...}> and the C<...> is not known to
2907Perl. The current valid ones are given in
2908L<perlrebackslash/\b{}, \b, \B{}, \B>.
2909
6e8a73f2 2910=item "%s" is more clearly written simply as "%s" in regex; marked by S<<-- HERE> in m/%s/
acdfc3b6
KW
2911
2912(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
2913
2914You specified a character that has the given plainer way of writing it,
2915and which is also portable to platforms running with different character
2916sets.
2917
4f650b80 2918=item $* is no longer supported
b4581f09 2919
4f650b80 2920(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2921perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2922previous versions of perl the use of C<$*> enabled or disabled multi-line
2923matching within a string.
4fd19576
B
2924
2925Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2926modifiers. You can enable C</m> for a lexical scope (even a whole file)
2927with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2928then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2929
8ae1fe26
RGS
2930=item $# is no longer supported
2931
a58ac25e 2932(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2933perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2934should use the printf/sprintf functions instead.
8ae1fe26 2935
ccf3535a 2936=item '%s' is not a code reference
6ad11d81 2937
6903afa2
FC
2938(W overload) The second (fourth, sixth, ...) argument of
2939overload::constant needs to be a code reference. Either
2940an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2941
ccf3535a 2942=item '%s' is not an overloadable type
6ad11d81 2943
04a80ee0
RGS
2944(W overload) You tried to overload a constant type the overload package is
2945unaware of.
6ad11d81 2946
5a25739d
FC
2947=item -i used with no filenames on the command line, reading from STDIN
2948
2949(S inplace) The C<-i> option was passed on the command line, indicating
2950that the script is intended to edit files in place, but no files were
2951given. This is usually a mistake, since editing STDIN in place doesn't
2952make sense, and can be confusing because it can make perl look like
2953it is hanging when it is really just trying to read from STDIN. You
2954should either pass a filename to edit, or remove C<-i> from the command
2955line. See L<perlrun> for more details.
2956
aec0ef10 2957=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2958
2959(P) The regular expression parser is confused.
2960
0953b66b
FC
2961=item keys on reference is experimental
2962
0773cb3e
FC
2963(S experimental::autoderef) C<keys> with a scalar argument is experimental
2964and may change or be removed in a future Perl version. If you want to
2965take the risk of using this feature, simply disable this warning:
0953b66b 2966
d401967c 2967 no warnings "experimental::autoderef";
0953b66b 2968
a0d0e21e
LW
2969=item Label not found for "last %s"
2970
be771a83
GS
2971(F) You named a loop to break out of, but you're not currently in a loop
2972of that name, not even if you count where you were called from. See
2973L<perlfunc/last>.
a0d0e21e
LW
2974
2975=item Label not found for "next %s"
2976
2977(F) You named a loop to continue, but you're not currently in a loop of
2978that name, not even if you count where you were called from. See
2979L<perlfunc/last>.
2980
2981=item Label not found for "redo %s"
2982
2983(F) You named a loop to restart, but you're not currently in a loop of
2984that name, not even if you count where you were called from. See
2985L<perlfunc/last>.
2986
85ab1d1d 2987=item leaving effective %s failed
5ff3f7a4 2988
85ab1d1d 2989(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2990effective uids or gids failed.
2991
49704364
LW
2992=item length/code after end of string in unpack
2993
d7f8936a 2994(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2995length/code combination tried to obtain more data. This results in
2996an undefined value for the length. See L<perlfunc/pack>.
49704364 2997
25e26107 2998=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2999
0d46a4e7
FC
3000(W syntax) You used length() on either an array or a hash when you
3001probably wanted a count of the items.
e508c8a4
MH
3002
3003Array size can be obtained by doing:
3004
3005 scalar(@array);
3006
3007The number of items in a hash can be obtained by doing:
3008
3009 scalar(keys %hash);
3010
f0e67a1d
Z
3011=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
3012
d4fe7078
RS
3013(F) An extension is attempting to insert text into the current parse
3014(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
3015couldn't be part of the current input. This is an inherent pitfall
3016of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 3017it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
3018
3019=item Lexing code internal error (%s)
3020
3021(F) Lexing code supplied by an extension violated the lexer's API in a
3022detectable way.
3023
69282e91 3024=item listen() on closed socket %s
a0d0e21e 3025
be771a83
GS
3026(W closed) You tried to do a listen on a closed socket. Did you forget
3027to check the return value of your socket() call? See
3028L<perlfunc/listen>.
a0d0e21e 3029
6651ba0b
FC
3030=item List form of piped open not implemented
3031
3032(F) On some platforms, notably Windows, the three-or-more-arguments
3033form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
3034Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
3035
dc6bb7ba
FC
3036=item %s: loadable library and perl binaries are mismatched (got handshake key %p, needed %p)
3037
3038(P) A dynamic loading library C<.so> or C<.dll> was being loaded into the
3039process that was built against a different build of perl than the
3040said library was compiled against. Reinstalling the XS module will
3041likely fix this error.
3042
8c6180a9
KW
3043=item Locale '%s' may not work well.%s
3044
780fcc9f
KW
3045(W locale) You are using the named locale, which is a non-UTF-8 one, and
3046which Perl has determined is not fully compatible with Perl. The second
3047C<%s> gives a reason.
8c6180a9
KW
3048
3049By far the most common reason is that the locale has characters in it
3050that are represented by more than one byte. The only such locales that
3051Perl can handle are the UTF-8 locales. Most likely the specified locale
3052is a non-UTF-8 one for an East Asian language such as Chinese or
3053Japanese. If the locale is a superset of ASCII, the ASCII portion of it
780fcc9f 3054may work in Perl.
8c6180a9
KW
3055
3056Some essentially obsolete locales that aren't supersets of ASCII, mainly
3057those in ISO 646 or other 7-bit locales, such as ASMO 449, can also have
3058problems, depending on what portions of the ASCII character set get
3059changed by the locale and are also used by the program.
3060The warning message lists the determinable conflicting characters.
3061
780fcc9f
KW
3062Note that not all incompatibilities are found.
3063
3064If this happens to you, there's not much you can do except switch to use a
3065different locale or use L<Encode> to translate from the locale into
3066UTF-8; if that's impracticable, you have been warned that some things
3067may break.
3068
3069This message is output once each time a bad locale is switched into
3070within the scope of C<S<use locale>>, or on the first possibly-affected
3071operation if the C<S<use locale>> inherits a bad one. It is not raised
3072for any operations from the L<POSIX> module.
3073
a2162cd9
FC
3074=item localtime(%f) failed
3075
3076(W overflow) You called C<localtime> with a number that it could not handle:
3077too large, too small, or NaN. The returned value is C<undef>.
3078
3079=item localtime(%f) too large
3080
3081(W overflow) You called C<localtime> with a number that was larger
3082than it can reliably handle and C<localtime> probably returned the
3083wrong date. This warning is also triggered with NaN (the special
3084not-a-number value).
3085
3086=item localtime(%f) too small
3087
3088(W overflow) You called C<localtime> with a number that was smaller
3089than it can reliably handle and C<localtime> probably returned the
3090wrong date.
3091
58e23c8d 3092=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
3093
3094(F) There is currently a limit on the length of string which lookbehind can
6903afa2 3095handle. This restriction may be eased in a future release.
2e50fd82 3096
b88df990
NC
3097=item Lost precision when %s %f by 1
3098
e63e8a91
FC
3099(W imprecision) The value you attempted to increment or decrement by one
3100is too large for the underlying floating point representation to store
3101accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
3102warning because it has already switched from integers to floating point
3103when values are too large for integers, and now even floating point is
3104insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 3105
93fad930 3106=item lstat() on filehandle%s
2f7da168
RK
3107
3108(W io) You tried to do an lstat on a filehandle. What did you mean
3109by that? lstat() makes sense only on filenames. (Perl did a fstat()
3110instead on the filehandle.)
3111
345d70e3 3112=item lvalue attribute %s already-defined subroutine
bb3abb05 3113
345d70e3
FC
3114(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
3115attribute on or off on a Perl subroutine that is already defined
3116does not always work properly. It may or may not do what you
3117want, depending on what code is inside the subroutine, with exact
3118details subject to change between Perl versions. Only do this
3119if you really know what you are doing.
bb3abb05 3120
885ef6f5
GG
3121=item lvalue attribute ignored after the subroutine has been defined
3122
345d70e3
FC
3123(W misc) Using the C<:lvalue> declarative syntax to make a Perl
3124subroutine an lvalue subroutine after it has been defined is
3125not permitted. To make the subroutine an lvalue subroutine,
3126add the lvalue attribute to the definition, or put the C<sub
3127foo :lvalue;> declaration before the definition.
3128
3129See also L<attributes.pm|attributes>.
885ef6f5 3130
6f1b3ab0
FC
3131=item Magical list constants are not supported
3132
3133(F) You assigned a magical array to a stash element, and then tried
3134to use the subroutine from the same slot. You are asking Perl to do
3135something it cannot do, details subject to change between Perl versions.
3136
2db62bbc 3137=item Malformed integer in [] in pack
49704364 3138
2db62bbc 3139(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
3140are permitted. See L<perlfunc/pack>.
3141
3142=item Malformed integer in [] in unpack
3143
2db62bbc 3144(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
3145are permitted. See L<perlfunc/pack>.
3146
6df41af2
GS
3147=item Malformed PERLLIB_PREFIX
3148
3149(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
3150
3151 prefix1;prefix2
3152
3153or
6df41af2
GS
3154 prefix1 prefix2
3155
be771a83
GS
3156with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
3157a builtin library search path, prefix2 is substituted. The error may
3158appear if components are not found, or are too long. See
fecfaeb8 3159"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 3160
2f758a16
ST
3161=item Malformed prototype for %s: %s
3162
d37a9538
ST
3163(F) You tried to use a function with a malformed prototype. The
3164syntax of function prototypes is given a brief compile-time check for
3165obvious errors like invalid characters. A more rigorous check is run
3166when the function is called.
30d9c59b
Z
3167Perhaps the function's author was trying to write a subroutine signature
3168but didn't enable that feature first (C<use feature 'signatures'>),
3169so the signature was instead interpreted as a bad prototype.
2f758a16 3170
ba210ebe
JH
3171=item Malformed UTF-8 character (%s)
3172
4d6f11e5 3173(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 3174encoding rules, even though it had the UTF8 flag on.
ba210ebe 3175
2575c402
JW
3176One possible cause is that you set the UTF8 flag yourself for data that
3177you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 31788-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
3179
3180If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
3181sequences are handled gracefully, but if you use C<:utf8>, the flag is
3182set without validating the data, possibly resulting in this error
3183message.
3184
3185See also L<Encode/"Handling Malformed Data">.
901b21bf 3186
107160e2
KW
3187=item Malformed UTF-8 character immediately after '%s'
3188
3189(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
3190encoding rules. The message prints out the properly encoded characters
3191just before the first bad one. If C<utf8> warnings are enabled, a
3192warning is generated that gives more details about the type of
3193malformation.
3194
bde9e88d 3195=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
3196
3197(F) The charnames handler returned malformed UTF-8.
3198
4a5d3a93
FC
3199=item Malformed UTF-8 string in '%c' format in unpack
3200
3201(F) You tried to unpack something that didn't comply with UTF-8 encoding
3202rules and perl was unable to guess how to make more progress.
3203
f337b084
TH
3204=item Malformed UTF-8 string in pack
3205
3206(F) You tried to pack something that didn't comply with UTF-8 encoding
3207rules and perl was unable to guess how to make more progress.
3208
3209=item Malformed UTF-8 string in unpack
3210
3211(F) You tried to unpack something that didn't comply with UTF-8 encoding
3212rules and perl was unable to guess how to make more progress.
3213
4a5d3a93 3214=item Malformed UTF-16 surrogate
f337b084 3215
4a5d3a93
FC
3216(F) Perl thought it was reading UTF-16 encoded character data but while
3217doing it Perl met a malformed Unicode surrogate.
3218
30d9c59b
Z
3219=item Mandatory parameter follows optional parameter
3220
3221(F) In a subroutine signature, you wrote something like "$a = undef,
3222$b", making an earlier parameter optional and a later one mandatory.
3223Parameters are filled from left to right, so it's impossible for the
3224caller to omit an earlier one and pass a later one. If you want to act
3225as if the parameters are filled from right to left, declare the rightmost
3226optional and then shuffle the parameters around in the subroutine's body.
3227
2d88a86a
KW
3228=item Matched non-Unicode code point 0x%X against Unicode property; may
3229not be portable
3230
3231(S non_unicode) Perl allows strings to contain a superset of
3232Unicode code points; each code point may be as large as what is storable
3233in an unsigned integer on your system, but these may not be accepted by
3234other languages/systems. This message occurs when you matched a string
3235containing such a code point against a regular expression pattern, and
3236the code point was matched against a Unicode property, C<\p{...}> or
3237C<\P{...}>. Unicode properties are only defined on Unicode code points,
3238so the result of this match is undefined by Unicode, but Perl (starting
3239in v5.20) treats non-Unicode code points as if they were typical
3240unassigned Unicode ones, and matched this one accordingly. Whether a
3241given property matches these code points or not is specified in
3242L<perluniprops/Properties accessible through \p{} and \P{}>.
3243
3244This message is suppressed (unless it has been made fatal) if it is
3245immaterial to the results of the match if the code point is Unicode or
3246not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
3247the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
3248Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
3249every code point except these 22.)
3250
3251Getting this message indicates that the outcome of the match arguably
3252should have been the opposite of what actually happened. If you think
3253that is the case, you may wish to make the C<non_unicode> warnings
3254category fatal; if you agree with Perl's decision, you may wish to turn
3255off this category.
3256
3257See L<perlunicode/Beyond Unicode code points> for more information.
3258
e0e4a6e3
FC
3259=item %s matches null string many times in regex; marked by S<<-- HERE> in
3260m/%s/
4a5d3a93
FC
3261
3262(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 3263regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 3264shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 3265See L<perlre>.
f337b084 3266
de42a5a9 3267=item Maximal count of pending signals (%u) exceeded
2563cec5 3268
6903afa2 3269(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
3270usually indicates that your operating system tried to deliver signals
3271too fast (with a very high priority), starving the perl process from
3272resources it would need to reach a point where it can process signals
6903afa2 3273safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 3274
25f58aea
PN
3275=item "%s" may clash with future reserved word
3276
3277(W) This warning may be due to running a perl5 script through a perl4
3278interpreter, especially if the word that is being warned about is
3279"use" or "my".
3280
0d2487cd 3281=item '%' may not be used in pack
6df41af2
GS
3282
3283(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
3284checksumming process loses information, and you can't go the other way.
3285See L<perlfunc/unpack>.
6df41af2 3286
a0d0e21e
LW
3287=item Method for operation %s not found in package %s during blessing
3288
3289(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 3290doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 3291
3cdd684c
TP
3292=item Method %s not permitted
3293
3294See Server error.
3295
a0d0e21e
LW
3296=item Might be a runaway multi-line %s string starting on line %d
3297
3298(S) An advisory indicating that the previous error may have been caused
3299by a missing delimiter on a string or pattern, because it eventually
3300ended earlier on the current line.
3301
3302=item Misplaced _ in number
3303
d4ced10d
JH
3304(W syntax) An underscore (underbar) in a numeric constant did not
3305separate two digits.
a0d0e21e 3306
7baa4690
HS
3307=item Missing argument in %s
3308
3664866e
AB
3309(W missing) You called a function with fewer arguments than other
3310arguments you supplied indicated would be needed.
3311
3312Currently only emitted when a printf-type format required more
3313arguments than were supplied, but might be used in the future for
3314other cases where we can statically determine that arguments to
3315functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3316
9e81e6a1
RGS
3317=item Missing argument to -%c
3318
3319(F) The argument to the indicated command line switch must follow
3320immediately after the switch, without intervening spaces.
3321
ff3f963a 3322=item Missing braces on \N{}
423cee85 3323
e0e4a6e3 3324=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3325
4a2d328f 3326(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3327double-quotish context. This can also happen when there is a space
3328(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3329This modifier does not change the requirement that the brace immediately
3330follow the C<\N>.
423cee85 3331
f0a2b745
KW
3332=item Missing braces on \o{}
3333
3334(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3335
a0d0e21e
LW
3336=item Missing comma after first argument to %s function
3337
3338(F) While certain functions allow you to specify a filehandle or an
3339"indirect object" before the argument list, this ain't one of them.
3340
06eaf0bc
GS
3341=item Missing command in piped open
3342
be771a83
GS
3343(W pipe) You used the C<open(FH, "| command")> or
3344C<open(FH, "command |")> construction, but the command was missing or
3345blank.
06eaf0bc 3346
961ce445
RGS
3347=item Missing control char name in \c
3348
3349(F) A double-quoted string ended with "\c", without the required control
3350character name.
3351
591f5ca2
FC
3352=item Missing ']' in prototype for %s : %s
3353
bfe11873 3354(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3355
8767b1ab 3356=item Missing name in "%s sub"
6df41af2 3357
87444db5 3358(F) The syntax for lexically scoped subroutines requires that