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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
4ad56ec9
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451=item Bad realloc() ignored
452
6903afa2
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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
4df3f177
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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
46e58bd2
AC
665=item Cannot yet reorder sv_catpvfn() arguments from va_list
666
667(F) Some XS code tried to use C<sv_catpvfn()> or a related function with a
668format string that specifies explicit indexes for some of the elements, and
669using a C-style variable-argument list (a C<va_list>). This is not currently
670supported. XS authors wanting to do this must instead construct a C array of
671C<SV*> scalars containing the arguments.
672
96ebfdd7
RK
673=item Can only compress unsigned integers in pack
674
675(F) An argument to pack("w",...) was not an integer. The BER compressed
676integer format can only be used with positive integers, and you attempted
677to compress something else. See L<perlfunc/pack>.
678
a0d0e21e
LW
679=item Can't bless non-reference value
680
681(F) Only hard references may be blessed. This is how Perl "enforces"
682encapsulation of objects. See L<perlobj>.
683
dc57907a
RGS
684=item Can't "break" in a loop topicalizer
685
0d863452 686(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 687a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
688
689=item Can't "break" outside a given block
dc57907a 690
0d863452
RH
691(F) You called C<break>, but you're not inside a C<given> block.
692
6df41af2
GS
693=item Can't call method "%s" on an undefined value
694
695(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
696object reference or package name contains an undefined value. Something
697like this will reproduce the error:
6df41af2
GS
698
699 $BADREF = undef;
700 process $BADREF 1,2,3;
701 $BADREF->process(1,2,3);
702
a0d0e21e
LW
703=item Can't call method "%s" on unblessed reference
704
54310121 705(F) A method call must know in what package it's supposed to run. It
be771a83
GS
706ordinarily finds this out from the object reference you supply, but you
707didn't supply an object reference in this case. A reference isn't an
708object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
709
710=item Can't call method "%s" without a package or object reference
711
712(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
713object reference or package name contains an expression that returns a
714defined value which is neither an object reference nor a package name.
72b5445b
GS
715Something like this will reproduce the error:
716
717 $BADREF = 42;
718 process $BADREF 1,2,3;
719 $BADREF->process(1,2,3);
720
dfe378f1
FC
721=item Can't call mro_isa_changed_in() on anonymous symbol table
722
723(P) Perl got confused as to whether a hash was a plain hash or a
724symbol table hash when trying to update @ISA caches.
725
2bf7e7b2
FC
726=item Can't call mro_method_changed_in() on anonymous symbol table
727
728(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
729not attached to the symbol table.
730
a0d0e21e
LW
731=item Can't chdir to %s
732
f703fc96 733(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
734that you can chdir to, possibly because it doesn't exist.
735
0545a864 736=item Can't check filesystem of script "%s" for nosuid
104d25b7 737
be771a83
GS
738(P) For some reason you can't check the filesystem of the script for
739nosuid.
104d25b7 740
22e74366 741=item Can't coerce %s to %s in %s
a0d0e21e
LW
742
743(F) Certain types of SVs, in particular real symbol table entries
55497cff 744(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
745say things like:
746
747 *foo += 1;
748
749You CAN say
750
751 $foo = *foo;
752 $foo += 1;
753
754but then $foo no longer contains a glob.
755
0d863452 756=item Can't "continue" outside a when block
dc57907a 757
0d863452
RH
758(F) You called C<continue>, but you're not inside a C<when>
759or C<default> block.
760
a0d0e21e
LW
761=item Can't create pipe mailbox
762
be771a83
GS
763(P) An error peculiar to VMS. The process is suffering from exhausted
764quotas or other plumbing problems.
a0d0e21e 765
eb64745e
GS
766=item Can't declare %s in "%s"
767
30c282f6
NC
768(F) Only scalar, array, and hash variables may be declared as "my", "our" or
769"state" variables. They must have ordinary identifiers as names.
a0d0e21e 770
fc7debfb
FC
771=item Can't "default" outside a topicalizer
772
773(F) You have used a C<default> block that is neither inside a
774C<foreach> loop nor a C<given> block. (Note that this error is
775issued on exit from the C<default> block, so you won't get the
776error if you use an explicit C<continue>.)
777
a2162cd9
FC
778=item Can't do inplace edit: %s is not a regular file
779
780(S inplace) You tried to use the B<-i> switch on a special file, such as
781a file in /dev, a FIFO or an uneditable directory. The file was ignored.
782
783=item Can't do inplace edit on %s: %s
784
785(S inplace) The creation of the new file failed for the indicated
786reason.
787
788=item Can't do inplace edit without backup
789
790(F) You're on a system such as MS-DOS that gets confused if you try
791reading from a deleted (but still opened) file. You have to say
792C<-i.bak>, or some such.
793
794=item Can't do inplace edit: %s would not be unique
795
796(S inplace) Your filesystem does not support filenames longer than 14
797characters and Perl was unable to create a unique filename during
798inplace editing with the B<-i> switch. The file was ignored.
799
ab0b796c
KW
800=item Can't do %s("%s") on non-UTF-8 locale; resolved to "%s".
801
802(W locale) You are 1) running under "C<use locale>"; 2) the current
803locale is not a UTF-8 one; 3) you tried to do the designated case-change
804operation on the specified Unicode character; and 4) the result of this
805operation would mix Unicode and locale rules, which likely conflict.
806Mixing of different rule types is forbidden, so the operation was not
807done; instead the result is the indicated value, which is the best
808available that uses entirely Unicode rules. That turns out to almost
809always be the original character, unchanged.
810
811It is generally a bad idea to mix non-UTF-8 locales and Unicode, and
812this issue is one of the reasons why. This warning is raised when
813Unicode rules would normally cause the result of this operation to
814contain a character that is in the range specified by the locale,
8150..255, and hence is subject to the locale's rules, not Unicode's.
816
817If you are using locale purely for its characteristics related to things
818like its numeric and time formatting (and not C<LC_CTYPE>), consider
819using a restricted form of the locale pragma (see L<perllocale/The "use
820locale" pragma>) like "S<C<use locale ':not_characters'>>".
821
822Note that failed case-changing operations done as a result of
823case-insensitive C</i> regular expression matching will show up in this
824warning as having the C<fc> operation (as that is what the regular
825expression engine calls behind the scenes.)
826
a0d0e21e
LW
827=item Can't do waitpid with flags
828
be771a83
GS
829(F) This machine doesn't have either waitpid() or wait4(), so only
830waitpid() without flags is emulated.
a0d0e21e 831
a0d0e21e
LW
832=item Can't emulate -%s on #! line
833
be771a83
GS
834(F) The #! line specifies a switch that doesn't make sense at this
835point. For example, it'd be kind of silly to put a B<-x> on the #!
836line.
a0d0e21e 837
1109a392
MHM
838=item Can't %s %s-endian %ss on this platform
839
840(F) Your platform's byte-order is neither big-endian nor little-endian,
841or it has a very strange pointer size. Packing and unpacking big- or
842little-endian floating point values and pointers may not be possible.
843See L<perlfunc/pack>.
844
a0d0e21e
LW
845=item Can't exec "%s": %s
846
d1be9408 847(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
848named program for the indicated reason. Typical reasons include: the
849permissions were wrong on the file, the file wasn't found in
850C<$ENV{PATH}>, the executable in question was compiled for another
851architecture, or the #! line in a script points to an interpreter that
852can't be run for similar reasons. (Or maybe your system doesn't support
853#! at all.)
a0d0e21e
LW
854
855=item Can't exec %s
856
be771a83
GS
857(F) Perl was trying to execute the indicated program for you because
858that's what the #! line said. If that's not what you wanted, you may
859need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
860
861=item Can't execute %s
862
be771a83
GS
863(F) You used the B<-S> switch, but the copies of the script to execute
864found in the PATH did not have correct permissions.
2a92aaa0 865
6df41af2 866=item Can't find an opnumber for "%s"
2a92aaa0 867
be771a83
GS
868(F) A string of a form C<CORE::word> was given to prototype(), but there
869is no builtin with the name C<word>.
6df41af2 870
56ca2fc0
JH
871=item Can't find %s character property "%s"
872
873(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 874could not be found. Maybe you misspelled the name of the property?
e1b711da 875See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 876for a complete list of available official properties.
56ca2fc0 877
6df41af2
GS
878=item Can't find label %s
879
be771a83
GS
880(F) You said to goto a label that isn't mentioned anywhere that it's
881possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
882
883=item Can't find %s on PATH
884
be771a83
GS
885(F) You used the B<-S> switch, but the script to execute could not be
886found in the PATH.
a0d0e21e 887
6df41af2 888=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 889
be771a83
GS
890(F) You used the B<-S> switch, but the script to execute could not be
891found in the PATH, or at least not with the correct permissions. The
892script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
893
894=item Can't find string terminator %s anywhere before EOF
895
be771a83
GS
896(F) Perl strings can stretch over multiple lines. This message means
897that the closing delimiter was omitted. Because bracketed quotes count
898nesting levels, the following is missing its final parenthesis:
a0d0e21e 899
fb73857a
PP
900 print q(The character '(' starts a side comment.);
901
97b3d10f 902If you're getting this error from a here-document, you may have
b6b8cb97
FC
903included unseen whitespace before or after your closing tag or there
904may not be a linebreak after it. A good programmer's editor will have
905a way to help you find these characters (or lack of characters). See
906L<perlop> for the full details on here-documents.
a0d0e21e 907
660a4616
ST
908=item Can't find Unicode property definition "%s"
909
5f8ad6b6
FC
910(F) You may have tried to use C<\p> which means a Unicode
911property (for example C<\p{Lu}> matches all uppercase
fa816bf3 912letters). If you did mean to use a Unicode property, see
e1b711da 913L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 914for a complete list of available properties. If you didn't
fa816bf3
FC
915mean to use a Unicode property, escape the C<\p>, either by
916C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 917until C<\E>).
660a4616 918
b3647a36 919=item Can't fork: %s
a0d0e21e 920
be771a83
GS
921(F) A fatal error occurred while trying to fork while opening a
922pipeline.
a0d0e21e 923
b3647a36
SR
924=item Can't fork, trying again in 5 seconds
925
c973c02e 926(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
927after five seconds.
928
748a9306
LW
929=item Can't get filespec - stale stat buffer?
930
be771a83
GS
931(S) A warning peculiar to VMS. This arises because of the difference
932between access checks under VMS and under the Unix model Perl assumes.
933Under VMS, access checks are done by filename, rather than by bits in
934the stat buffer, so that ACLs and other protections can be taken into
935account. Unfortunately, Perl assumes that the stat buffer contains all
936the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 937the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
938the device name and FID present in the stat buffer, but this works only
939if you haven't made a subsequent call to the CRTL stat() routine,
940because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
941appears, the name lookup failed, and the access-checking routine gave up
942and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
943routine knows about the Perl C<stat> operator and file tests, so you
944shouldn't ever see this warning in response to a Perl command; it arises
945only if some internal code takes stat buffers lightly.)
748a9306 946
a0d0e21e
LW
947=item Can't get pipe mailbox device name
948
be771a83
GS
949(P) An error peculiar to VMS. After creating a mailbox to act as a
950pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
951
952=item Can't get SYSGEN parameter value for MAXBUF
953
748a9306
LW
954(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
955mailbox buffers to be, and didn't get an answer.
a0d0e21e 956
6df41af2 957=item Can't "goto" into the middle of a foreach loop
a0d0e21e 958
be771a83
GS
959(F) A "goto" statement was executed to jump into the middle of a foreach
960loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
961
962=item Can't "goto" out of a pseudo block
963
be771a83
GS
964(F) A "goto" statement was executed to jump out of what might look like
965a block, except that it isn't a proper block. This usually occurs if
966you tried to jump out of a sort() block or subroutine, which is a no-no.
967See L<perlfunc/goto>.
a0d0e21e 968
5a25739d
FC
969=item Can't goto subroutine from an eval-%s
970
971(F) The "goto subroutine" call can't be used to jump out of an eval
972"string" or block.
973
9850bf21 974=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 975
9850bf21
RH
976(F) The "goto subroutine" call can't be used to jump out of the
977comparison sub for a sort(), or from a similar callback (such
978as the reduce() function in List::Util).
979
6df41af2
GS
980=item Can't goto subroutine outside a subroutine
981
be771a83
GS
982(F) The deeply magical "goto subroutine" call can only replace one
983subroutine call for another. It can't manufacture one out of whole
984cloth. In general you should be calling it out of only an AUTOLOAD
985routine anyway. See L<perlfunc/goto>.
6df41af2 986
0b5b802d
GS
987=item Can't ignore signal CHLD, forcing to default
988
be771a83
GS
989(W signal) Perl has detected that it is being run with the SIGCHLD
990signal (sometimes known as SIGCLD) disabled. Since disabling this
991signal will interfere with proper determination of exit status of child
992processes, Perl has reset the signal to its default value. This
993situation typically indicates that the parent program under which Perl
994may be running (e.g. cron) is being very careless.
0b5b802d 995
e2c0f81f
DG
996=item Can't kill a non-numeric process ID
997
998(F) Process identifiers must be (signed) integers. It is a fatal error to
999attempt to kill() an undefined, empty-string or otherwise non-numeric
1000process identifier.
1001
6df41af2 1002=item Can't "last" outside a loop block
4633a7c4 1003
6df41af2 1004(F) A "last" statement was executed to break out of the current block,
be771a83
GS
1005except that there's this itty bitty problem called there isn't a current
1006block. Note that an "if" or "else" block doesn't count as a "loopish"
1007block, as doesn't a block given to sort(), map() or grep(). You can
1008usually double the curlies to get the same effect though, because the
1009inner curlies will be considered a block that loops once. See
1010L<perlfunc/last>.
4633a7c4 1011
2c7d6b9c
RGS
1012=item Can't linearize anonymous symbol table
1013
1014(F) Perl tried to calculate the method resolution order (MRO) of a
1015package, but failed because the package stash has no name.
1016
b8170e59
JB
1017=item Can't load '%s' for module %s
1018
6903afa2
FC
1019(F) The module you tried to load failed to load a dynamic extension.
1020This may either mean that you upgraded your version of perl to one
1021that is incompatible with your old dynamic extensions (which is known
1022to happen between major versions of perl), or (more likely) that your
1023dynamic extension was built against an older version of the library
1024that is installed on your system. You may need to rebuild your old
1025dynamic extensions.
b8170e59 1026
748a9306
LW
1027=item Can't localize lexical variable %s
1028
2ba9eb46 1029(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
1030lexical variable using "my" or "state". This is not allowed. If you
1031want to localize a package variable of the same name, qualify it with
1032the package name.
748a9306 1033
6df41af2 1034=item Can't localize through a reference
4727527e 1035
6df41af2
GS
1036(F) You said something like C<local $$ref>, which Perl can't currently
1037handle, because when it goes to restore the old value of whatever $ref
be771a83 1038pointed to after the scope of the local() is finished, it can't be sure
64977eb6 1039that $ref will still be a reference.
4727527e 1040
ea071790 1041=item Can't locate %s
ec889f3a 1042
fa816bf3
FC
1043(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
1044Perl looks for the file in all the locations mentioned in @INC, unless
1045the file name included the full path to the file. Perhaps you need
1046to set the PERL5LIB or PERL5OPT environment variable to say where the
1047extra library is, or maybe the script needs to add the library name
be771a83
GS
1048to @INC. Or maybe you just misspelled the name of the file. See
1049L<perlfunc/require> and L<lib>.
a0d0e21e 1050
6df41af2
GS
1051=item Can't locate auto/%s.al in @INC
1052
be771a83
GS
1053(F) A function (or method) was called in a package which allows
1054autoload, but there is no function to autoload. Most probable causes
1055are a misprint in a function/method name or a failure to C<AutoSplit>
1056the file, say, by doing C<make install>.
6df41af2 1057
b8170e59
JB
1058=item Can't locate loadable object for module %s in @INC
1059
1060(F) The module you loaded is trying to load an external library, like
d70d8e57 1061for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1062unable to locate this library. See L<DynaLoader>.
1063
a0d0e21e
LW
1064=item Can't locate object method "%s" via package "%s"
1065
1066(F) You called a method correctly, and it correctly indicated a package
1067functioning as a class, but that package doesn't define that particular
2ba9eb46 1068method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1069
8af56b9d
FC
1070=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1071to load "%s"?)
1072
1073(F) You called a method on a class that did not exist, and the method
1074could not be found in UNIVERSAL. This often means that a method
1075requires a package that has not been loaded.
1076
a0d0e21e
LW
1077=item Can't locate package %s for @%s::ISA
1078
be771a83
GS
1079(W syntax) The @ISA array contained the name of another package that
1080doesn't seem to exist.
a0d0e21e 1081
2f7da168
RK
1082=item Can't locate PerlIO%s
1083
1084(F) You tried to use in open() a PerlIO layer that does not exist,
1085e.g. open(FH, ">:nosuchlayer", "somefile").
1086
f4ad53f4 1087=item Can't make list assignment to %ENV on this system
3e3baf6d 1088
be771a83
GS
1089(F) List assignment to %ENV is not supported on some systems, notably
1090VMS.
3e3baf6d 1091
cd40cd58
NC
1092=item Can't make loaded symbols global on this platform while loading %s
1093
ff9c1ae8 1094(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1095that symbols from the stated file are made available globally within the
1096process, but that functionality is not available on this platform. Whilst
1097the module likely will still work, this may prevent the perl interpreter
1098from loading other XS-based extensions which need to link directly to
1099functions defined in the C or XS code in the stated file.
1100
a0d0e21e
LW
1101=item Can't modify %s in %s
1102
be771a83
GS
1103(F) You aren't allowed to assign to the item indicated, or otherwise try
1104to change it, such as with an auto-increment.
a0d0e21e 1105
54310121 1106=item Can't modify nonexistent substring
a0d0e21e
LW
1107
1108(P) The internal routine that does assignment to a substr() was handed
1109a NULL.
1110
0f948285 1111=item Can't modify non-lvalue subroutine call of &%s
6df41af2
GS
1112
1113(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1114such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1115
cf6e1fa1
FC
1116=item Can't modify reference to %s in %s assignment
1117
1118(F) Only a limited number of constructs can be used as the argument to a
1119reference constructor on the left-hand side of an assignment, and what
1120you used was not one of them. See L<perlref/Assigning to References>.
1121
1122=item Can't modify reference to localized parenthesized array in list
1123assignment
1124
1125(F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1126it is not clear exactly what it should do. If you meant to make @array
1127refer to some other array, use C<\@array = \@other_array>. If you want to
1128make the elements of @array aliases of the scalars referenced on the
1129right-hand side, use C<\(@array) = @scalar_refs>.
1130
1131=item Can't modify reference to parenthesized hash in list assignment
1132
1133(F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1134refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1135make the elements of %hash into aliases of the scalars referenced on the
1136right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1137
5f05dabc 1138=item Can't msgrcv to read-only var
a0d0e21e 1139
5f05dabc 1140(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1141buffer.
1142
6df41af2
GS
1143=item Can't "next" outside a loop block
1144
1145(F) A "next" statement was executed to reiterate the current block, but
1146there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1147count as a "loopish" block, as doesn't a block given to sort(), map() or
1148grep(). You can usually double the curlies to get the same effect
1149though, because the inner curlies will be considered a block that loops
1150once. See L<perlfunc/next>.
6df41af2 1151
a0d0e21e
LW
1152=item Can't open %s: %s
1153
c47ff5f1 1154(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1155filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1156switches, or explicitly, failed for the indicated reason. Usually
1157this is because you don't have read permission for a file which
1158you named on the command line.
1159
1160(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1161your operating system's equivalent) could not be opened.
a0d0e21e 1162
9a869a14
RGS
1163=item Can't open a reference
1164
1165(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1166using the 3-arg open() syntax:
9a869a14
RGS
1167
1168 open FH, '>', $ref;
1169
1170but your version of perl is compiled without perlio, and this form of
1171open is not supported.
1172
a0d0e21e
LW
1173=item Can't open bidirectional pipe
1174
be771a83
GS
1175(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1176You can try any of several modules in the Perl library to do this, such
1177as IPC::Open2. Alternately, direct the pipe's output to a file using
1178">", and then read it in under a different file handle.
a0d0e21e 1179
748a9306
LW
1180=item Can't open error file %s as stderr
1181
be771a83
GS
1182(F) An error peculiar to VMS. Perl does its own command line
1183redirection, and couldn't open the file specified after '2>' or '2>>' on
1184the command line for writing.
748a9306
LW
1185
1186=item Can't open input file %s as stdin
1187
be771a83
GS
1188(F) An error peculiar to VMS. Perl does its own command line
1189redirection, and couldn't open the file specified after '<' on the
1190command line for reading.
748a9306
LW
1191
1192=item Can't open output file %s as stdout
1193
be771a83
GS
1194(F) An error peculiar to VMS. Perl does its own command line
1195redirection, and couldn't open the file specified after '>' or '>>' on
1196the command line for writing.
748a9306
LW
1197
1198=item Can't open output pipe (name: %s)
1199
be771a83
GS
1200(P) An error peculiar to VMS. Perl does its own command line
1201redirection, and couldn't open the pipe into which to send data destined
1202for stdout.
748a9306 1203
3b1cf97d 1204=item Can't open perl script "%s": %s
a0d0e21e
LW
1205
1206(F) The script you specified can't be opened for the indicated reason.
1207
fa3aa65a
JC
1208If you're debugging a script that uses #!, and normally relies on the
1209shell's $PATH search, the -S option causes perl to do that search, so
1210you don't have to type the path or C<`which $scriptname`>.
1211
6df41af2
GS
1212=item Can't read CRTL environ
1213
1214(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1215from the CRTL's internal environment array and discovered the array was
1216missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1217or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1218searched.
6df41af2 1219
f3106bc8
LM
1220=item Can't redeclare "%s" in "%s"
1221
1222(F) A "my", "our" or "state" declaration was found within another declaration,
1223such as C<my ($x, my($y), $z)> or C<our (my $x)>.
1224
6df41af2
GS
1225=item Can't "redo" outside a loop block
1226
1227(F) A "redo" statement was executed to restart the current block, but
1228there isn't a current block. Note that an "if" or "else" block doesn't
1229count as a "loopish" block, as doesn't a block given to sort(), map()
1230or grep(). You can usually double the curlies to get the same effect
1231though, because the inner curlies will be considered a block that
1232loops once. See L<perlfunc/redo>.
1233
64977eb6 1234=item Can't remove %s: %s, skipping file
10f9c03d 1235
be771a83
GS
1236(S inplace) You requested an inplace edit without creating a backup
1237file. Perl was unable to remove the original file to replace it with
1238the modified file. The file was left unmodified.
10f9c03d 1239
a0d0e21e
LW
1240=item Can't rename %s to %s: %s, skipping file
1241
e476b1b5 1242(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1243probably because you don't have write permission to the directory.
a0d0e21e 1244
748a9306
LW
1245=item Can't reopen input pipe (name: %s) in binary mode
1246
be771a83
GS
1247(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1248to reopen it to accept binary data. Alas, it failed.
748a9306 1249
9415f659
KW
1250=item Can't represent character for Ox%X on this platform
1251
1252(F) There is a hard limit to how big a character code point can be due
1253to the fundamental properties of UTF-8, especially on EBCDIC
1254platforms. The given code point exceeds that. The only work-around is
1255to not use such a large code point.
1256
4f12ec0e
FC
1257=item Can't reset %ENV on this system
1258
1259(F) You called C<reset('E')> or similar, which tried to reset
1260all variables in the current package beginning with "E". In
1261the main package, that includes %ENV. Resetting %ENV is not
1262supported on some systems, notably VMS.
1263
fe13d51d 1264=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1265
1fa582fa
FC
1266(F)(P) Error resolving overloading specified by a method name (as
1267opposed to a subroutine reference): no such method callable via the
1268package. If the method name is C<???>, this is an internal error.
6df41af2 1269
cd06dffe
GS
1270=item Can't return %s from lvalue subroutine
1271
be771a83
GS
1272(F) Perl detected an attempt to return illegal lvalues (such as
1273temporary or readonly values) from a subroutine used as an lvalue. This
1274is not allowed.
cd06dffe 1275
96ebfdd7
RK
1276=item Can't return outside a subroutine
1277
1278(F) The return statement was executed in mainline code, that is, where
1279there was no subroutine call to return out of. See L<perlsub>.
1280
78f9721b
SM
1281=item Can't return %s to lvalue scalar context
1282
6903afa2
FC
1283(F) You tried to return a complete array or hash from an lvalue
1284subroutine, but you called the subroutine in a way that made Perl
1285think you meant to return only one value. You probably meant to
1286write parentheses around the call to the subroutine, which tell
1287Perl that the call should be in list context.
78f9721b 1288
a0d0e21e
LW
1289=item Can't stat script "%s"
1290
be771a83
GS
1291(P) For some reason you can't fstat() the script even though you have it
1292open already. Bizarre.
a0d0e21e 1293
a0d0e21e
LW
1294=item Can't take log of %g
1295
fb73857a 1296(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1297negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1298standard with Perl, though, if you really want to do that for the
1299negative numbers.
a0d0e21e
LW
1300
1301=item Can't take sqrt of %g
1302
1303(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1304negative number. There's a Math::Complex package that comes standard
1305with Perl, though, if you really want to do that.
a0d0e21e
LW
1306
1307=item Can't undef active subroutine
1308
1309(F) You can't undefine a routine that's currently running. You can,
1310however, redefine it while it's running, and you can even undef the
1311redefined subroutine while the old routine is running. Go figure.
1312
c81225bc 1313=item Can't upgrade %s (%d) to %d
a0d0e21e 1314
be771a83
GS
1315(P) The internal sv_upgrade routine adds "members" to an SV, making it
1316into a more specialized kind of SV. The top several SV types are so
1317specialized, however, that they cannot be interconverted. This message
1318indicates that such a conversion was attempted.
a0d0e21e 1319
6651ba0b
FC
1320=item Can't use '%c' after -mname
1321
1322(F) You tried to call perl with the B<-m> switch, but you put something
1323other than "=" after the module name.
1324
1f1ec7b5
KW
1325=item Can't use a hash as a reference
1326
1327(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1328C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1329<= 5.22.0 used to allow this syntax, but shouldn't
1330have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1331
1332=item Can't use an array as a reference
1333
1334(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1335C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1336used to allow this syntax, but shouldn't have. This
1337was deprecated in perl 5.6.1.
1f1ec7b5 1338
1db89ea5
BS
1339=item Can't use anonymous symbol table for method lookup
1340
e27ad1f2 1341(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1342table that doesn't have a name. Symbol tables can become anonymous
1343for example by undefining stashes: C<undef %Some::Package::>.
1344
96ebfdd7
RK
1345=item Can't use an undefined value as %s reference
1346
1347(F) A value used as either a hard reference or a symbolic reference must
1348be a defined value. This helps to delurk some insidious errors.
1349
6df41af2
GS
1350=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1351
be771a83
GS
1352(F) Only hard references are allowed by "strict refs". Symbolic
1353references are disallowed. See L<perlref>.
6df41af2 1354
90b75b61 1355=item Can't use %! because Errno.pm is not available
1d2dff63 1356
20561843 1357(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1358Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1359provide symbolic names for C<$!> errno values.
1360
1109a392
MHM
1361=item Can't use both '<' and '>' after type '%c' in %s
1362
1363(F) A type cannot be forced to have both big-endian and little-endian
1364byte-order at the same time, so this combination of modifiers is not
1365allowed. See L<perlfunc/pack>.
1366
e35475de
KW
1367=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1368
1369(F) defined() is not useful on arrays because it
1370checks for an undefined I<scalar> value. If you want to see if the
1371array is empty, just use C<if (@array) { # not empty }> for example.
1372
1373=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1374
1375(F) C<defined()> is not usually right on hashes.
1376
1377Although C<defined %hash> is false on a plain not-yet-used hash, it
1378becomes true in several non-obvious circumstances, including iterators,
1379weak references, stash names, even remaining true after C<undef %hash>.
1380These things make C<defined %hash> fairly useless in practice, so it now
1381generates a fatal error.
1382
1383If a check for non-empty is what you wanted then just put it in boolean
1384context (see L<perldata/Scalar values>):
1385
1386 if (%hash) {
1387 # not empty
1388 }
1389
1390If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1391variable exists then that's never really been reliable, and isn't
1392a good way to enquire about the features of a package, or whether
1393it's loaded, etc.
1394
6df41af2
GS
1395=item Can't use %s for loop variable
1396
c1f06047 1397(P) The parser got confused when trying to parse a C<foreach> loop.
6df41af2 1398
aab6a793 1399=item Can't use global %s in "%s"
6df41af2 1400
be771a83
GS
1401(F) You tried to declare a magical variable as a lexical variable. This
1402is not allowed, because the magic can be tied to only one location
1403(namely the global variable) and it would be incredibly confusing to
1404have variables in your program that looked like magical variables but
6df41af2
GS
1405weren't.
1406
6d3b25aa
RGS
1407=item Can't use '%c' in a group with different byte-order in %s
1408
1409(F) You attempted to force a different byte-order on a type
1410that is already inside a group with a byte-order modifier.
1411For example you cannot force little-endianness on a type that
1412is inside a big-endian group.
1413
c07a80fd
PP
1414=item Can't use "my %s" in sort comparison
1415
1416(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1417You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1418and the variable had earlier been declared as a lexical variable.
1419Either qualify the sort variable with the package name, or rename the
1420lexical variable.
1421
a0d0e21e
LW
1422=item Can't use %s ref as %s ref
1423
1424(F) You've mixed up your reference types. You have to dereference a
1425reference of the type needed. You can use the ref() function to
1426test the type of the reference, if need be.
1427
748a9306 1428=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1429
5e634d20
FC
1430=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1431
b41bf23f
FC
1432(F) You've told Perl to dereference a string, something which
1433C<use strict> blocks to prevent it happening accidentally. See
1434L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1435in a double-quoted string immediately before interpolating a variable,
1436for example in C<"user @$twitter_id">, which says to treat the contents
1437of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1438symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1439
748a9306
LW
1440=item Can't use subscript on %s
1441
1442(F) The compiler tried to interpret a bracketed expression as a
1443subscript. But to the left of the brackets was an expression that
209e7cf1 1444didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1445
6df41af2
GS
1446=item Can't use \%c to mean $%c in expression
1447
75b44862
GS
1448(W syntax) In an ordinary expression, backslash is a unary operator that
1449creates a reference to its argument. The use of backslash to indicate a
1450backreference to a matched substring is valid only as part of a regular
be771a83
GS
1451expression pattern. Trying to do this in ordinary Perl code produces a
1452value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1453instead.
6df41af2 1454
810b8aa5
GS
1455=item Can't weaken a nonreference
1456
1457(F) You attempted to weaken something that was not a reference. Only
1458references can be weakened.
1459
fc7debfb
FC
1460=item Can't "when" outside a topicalizer
1461
1462(F) You have used a when() block that is neither inside a C<foreach>
1463loop nor a C<given> block. (Note that this error is issued on exit
1464from the C<when> block, so you won't get the error if the match fails,
1465or if you use an explicit C<continue>.)
1466
5f05dabc 1467=item Can't x= to read-only value
a0d0e21e 1468
be771a83
GS
1469(F) You tried to repeat a constant value (often the undefined value)
1470with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1471Perhaps you need to copy the value to a temporary, and repeat that.
1472
a04e6aad 1473=item Character following "\c" must be printable ASCII
f9d13529 1474
7357bd17 1475(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1476
727b6379 1477Note that ASCII characters that don't map to control characters are
7357bd17 1478discouraged, and will generate the warning (when enabled)
727b6379 1479L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1480
f337b084 1481=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1482
1483(W pack) You said
1484
1485 pack("C", $x)
1486
1487where $x is either less than 0 or more than 255; the C<"C"> format is
1488only for encoding native operating system characters (ASCII, EBCDIC,
1489and so on) and not for Unicode characters, so Perl behaved as if you meant
1490
1491 pack("C", $x & 255)
1492
1493If you actually want to pack Unicode codepoints, use the C<"U"> format
1494instead.
1495
f337b084 1496=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1497
1498(W pack) You said
1499
1500 pack("c", $x)
1501
1502where $x is either less than -128 or more than 127; the C<"c"> format
1503is only for encoding native operating system characters (ASCII, EBCDIC,
1504and so on) and not for Unicode characters, so Perl behaved as if you meant
1505
1506 pack("c", $x & 255);
1507
1508If you actually want to pack Unicode codepoints, use the C<"U"> format
1509instead.
1510
f337b084
TH
1511=item Character in '%c' format wrapped in unpack
1512
1513(W unpack) You tried something like
1514
1515 unpack("H", "\x{2a1}")
1516
1a147d38 1517where the format expects to process a byte (a character with a value
6903afa2
FC
1518below 256), but a higher value was provided instead. Perl uses the
1519value modulus 256 instead, as if you had provided:
f337b084
TH
1520
1521 unpack("H", "\x{a1}")
1522
5a25739d
FC
1523=item Character in 'W' format wrapped in pack
1524
1525(W pack) You said
1526
1527 pack("U0W", $x)
1528
1529where $x is either less than 0 or more than 255. However, C<U0>-mode
1530expects all values to fall in the interval [0, 255], so Perl behaved
1531as if you meant:
1532
1533 pack("U0W", $x & 255)
1534
f337b084
TH
1535=item Character(s) in '%c' format wrapped in pack
1536
1537(W pack) You tried something like
1538
1539 pack("u", "\x{1f3}b")
1540
1a147d38 1541where the format expects to process a sequence of bytes (character with a
6903afa2 1542value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1543uses the character values modulus 256 instead, as if you had provided:
1544
1545 pack("u", "\x{f3}b")
1546
1547=item Character(s) in '%c' format wrapped in unpack
1548
1549(W unpack) You tried something like
1550
1551 unpack("s", "\x{1f3}b")
1552
1a147d38 1553where the format expects to process a sequence of bytes (character with a
6903afa2 1554value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1555uses the character values modulus 256 instead, as if you had provided:
1556
1557 unpack("s", "\x{f3}b")
1558
f51551f7
FC
1559=item charnames alias definitions may not contain a sequence of multiple spaces
1560
1561(F) You defined a character name which had multiple space characters
1562in a row. Change them to single spaces. Usually these names are
1563defined in the C<:alias> import argument to C<use charnames>, but they
1564could be defined by a translator installed into C<$^H{charnames}>. See
1565L<charnames/CUSTOM ALIASES>.
1566
1567=item charnames alias definitions may not contain trailing white-space
1568
1569(F) You defined a character name which ended in a space
1570character. Remove the trailing space(s). Usually these names are
1571defined in the C<:alias> import argument to C<use charnames>, but they
1572could be defined by a translator installed into C<$^H{charnames}>.
1573See L<charnames/CUSTOM ALIASES>.
1574
60121127
TC
1575=item chdir() on unopened filehandle %s
1576
1577(W unopened) You tried chdir() on a filehandle that was never opened.
1578
33c28ab2
DM
1579=item \C no longer supported in regex; marked by S<<-- HERE> in m/%s/
1580
1581(F) The \C character class used to allow a match of single byte within a
1582multi-byte utf-8 character, but was removed in v5.24 as it broke
1583encapsulation and its implementation was extremely buggy. If you really
1584need to process the individual bytes, you probably want to convert your
1585string to one where each underlying byte is stored as a character, with
1586utf8::encode().
f51551f7 1587
f866a7cd
FC
1588=item "\c%c" is more clearly written simply as "%s"
1589
1590(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1591non-printable characters. You used it for a printable one, which
1592is better written as simply itself, perhaps preceded by a backslash
1593for non-word characters. Doing it the way you did is not portable
1594between ASCII and EBCDIC platforms.
f866a7cd 1595
6651ba0b
FC
1596=item Cloning substitution context is unimplemented
1597
1598(F) Creating a new thread inside the C<s///> operator is not supported.
1599
abc7ecad
SP
1600=item closedir() attempted on invalid dirhandle %s
1601
1602(W io) The dirhandle you tried to close is either closed or not really
1603a dirhandle. Check your control flow.
1604
5a25739d
FC
1605=item close() on unopened filehandle %s
1606
1607(W unopened) You tried to close a filehandle that was never opened.
1608
541ed3a9
FC
1609=item Closure prototype called
1610
1611(F) If a closure has attributes, the subroutine passed to an attribute
1612handler is the prototype that is cloned when a new closure is created.
1613This subroutine cannot be called.
1614
49704364
LW
1615=item Code missing after '/'
1616
6903afa2
FC
1617(F) You had a (sub-)template that ends with a '/'. There must be
1618another template code following the slash. See L<perlfunc/pack>.
49704364 1619
5a25739d
FC
1620=item Code point 0x%X is not Unicode, may not be portable
1621
2d88a86a 1622(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1623of U+10FFFF.
1624
1625Perl allows strings to contain a superset of Unicode code points, up
1626to the limit of what is storable in an unsigned integer on your system,
1627but these may not be accepted by other languages/systems. At one time,
1628it was legal in some standards to have code points up to 0x7FFF_FFFF,
1629but not higher. Code points above 0xFFFF_FFFF require larger than a
163032 bit word.
0876b9a0 1631
6df41af2
GS
1632=item %s: Command not found
1633
a892b81a 1634(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1635instead of Perl. Check the #! line, or manually feed your script into
1636Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1637
1638 #!/usr/bin/perl -w
6df41af2 1639
7a2e2cd6
PP
1640=item Compilation failed in require
1641
1642(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1643Perl uses this generic message when none of the errors that it
1644encountered were severe enough to halt compilation immediately.
7a2e2cd6 1645
c3464db5
DD
1646=item Complex regular subexpression recursion limit (%d) exceeded
1647
be771a83
GS
1648(W regexp) The regular expression engine uses recursion in complex
1649situations where back-tracking is required. Recursion depth is limited
1650to 32766, or perhaps less in architectures where the stack cannot grow
1651arbitrarily. ("Simple" and "medium" situations are handled without
1652recursion and are not subject to a limit.) Try shortening the string
1653under examination; looping in Perl code (e.g. with C<while>) rather than
1654in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1655that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1656on I<Mastering Regular Expressions>.)
c3464db5 1657
69282e91 1658=item connect() on closed socket %s
a0d0e21e 1659
be771a83
GS
1660(W closed) You tried to do a connect on a closed socket. Did you forget
1661to check the return value of your socket() call? See
1662L<perlfunc/connect>.
a0d0e21e 1663
e21e7c6a
FC
1664=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1665
1666(F) The subroutine registered to handle constant overloading
1667(see L<overload>) or a custom charnames handler (see
1668L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1669
1670=item Constant(%s): $^H{%s} is not defined
1671
1672(F) The parser found inconsistencies while attempting to define an
1673overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1674L<overload> pragma?
e21e7c6a 1675
779c5bc9
GS
1676=item Constant is not %s reference
1677
1678(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1679is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1680The message indicates the type of reference that was expected. This
be771a83 1681usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1682See L<perlsub/"Constant Functions"> and L<constant>.
1683
0ac016fc
FC
1684=item Constants from lexical variables potentially modified elsewhere are
1685deprecated
1686
1687(D deprecated) You wrote something like
1688
1689 my $var;
1690 $sub = sub () { $var };
1691
1692but $var is referenced elsewhere and could be modified after the C<sub>
1693expression is evaluated. Either it is explicitly modified elsewhere
1694(C<$var = 3>) or it is passed to a subroutine or to an operator like
1695C<printf> or C<map>, which may or may not modify the variable.
1696
1697Traditionally, Perl has captured the value of the variable at that
1698point and turned the subroutine into a constant eligible for inlining.
1699In those cases where the variable can be modified elsewhere, this
1700breaks the behavior of closures, in which the subroutine captures
1701the variable itself, rather than its value, so future changes to the
1702variable are reflected in the subroutine's return value.
1703
1704This usage is deprecated, because the behavior is likely to change
1705in a future version of Perl.
1706
1707If you intended for the subroutine to be eligible for inlining, then
1708make sure the variable is not referenced elsewhere, possibly by
1709copying it:
1710
1711 my $var2 = $var;
1712 $sub = sub () { $var2 };
1713
1714If you do want this subroutine to be a closure that reflects future
1715changes to the variable that it closes over, add an explicit C<return>:
1716
1717 my $var;
1718 $sub = sub () { return $var };
1719
4cee8e80
CS
1720=item Constant subroutine %s redefined
1721
aeb94125
FC
1722(W redefine)(S) You redefined a subroutine which had previously
1723been eligible for inlining. See L<perlsub/"Constant Functions">
1724for commentary and workarounds.
4cee8e80 1725
9607fc9c
PP
1726=item Constant subroutine %s undefined
1727
be771a83
GS
1728(W misc) You undefined a subroutine which had previously been eligible
1729for inlining. See L<perlsub/"Constant Functions"> for commentary and
1730workarounds.
9607fc9c 1731
5a25739d
FC
1732=item Constant(%s) unknown
1733
1734(F) The parser found inconsistencies either while attempting
1735to define an overloaded constant, or when trying to find the
1736character name specified in the C<\N{...}> escape. Perhaps you
3ee1a09c 1737forgot to load the corresponding L<overload> pragma?
5a25739d 1738
4a873d7a
FC
1739=item :const is experimental
1740
1741(S experimental::const_attr) The "const" attribute is experimental.
1742If you want to use the feature, disable the warning with C<no warnings
1743'experimental::const_attr'>, but know that in doing so you are taking
1744the risk that your code may break in a future Perl version.
1745
b77472f9
FC
1746=item :const is not permitted on named subroutines
1747
1748(F) The "const" attribute causes an anonymous subroutine to be run and
465068b9 1749its value captured at the time that it is cloned. Named subroutines are
b77472f9
FC
1750not cloned like this, so the attribute does not make sense on them.
1751
e7ea3e70
IZ
1752=item Copy method did not return a reference
1753
6903afa2 1754(F) The method which overloads "=" is buggy. See
13a2d996 1755L<overload/Copy Constructor>.
e7ea3e70 1756
4aaa4757
FC
1757=item &CORE::%s cannot be called directly
1758
1759(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1760with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1761in this package cannot yet be called that way, but must be
1762called as barewords. Something like this will work:
1763
1764 BEGIN { *shove = \&CORE::push; }
1765 shove @array, 1,2,3; # pushes on to @array
1766
6798c92b
GS
1767=item CORE::%s is not a keyword
1768
1769(F) The CORE:: namespace is reserved for Perl keywords.
1770
675fa9ff
FC
1771=item Corrupted regexp opcode %d > %d
1772
1773(P) This is either an error in Perl, or, if you're using
1774one, your L<custom regular expression engine|perlreapi>. If not the
1775latter, report the problem through the L<perlbug> utility.
1776
a0d0e21e
LW
1777=item corrupted regexp pointers
1778
1779(P) The regular expression engine got confused by what the regular
1780expression compiler gave it.
1781
1782=item corrupted regexp program
1783
be771a83
GS
1784(P) The regular expression engine got passed a regexp program without a
1785valid magic number.
a0d0e21e 1786
de42a5a9 1787=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1788
1789(P) The malloc package that comes with Perl had an internal failure.
1790
49704364
LW
1791=item Count after length/code in unpack
1792
1793(F) You had an unpack template indicating a counted-length string, but
1794you have also specified an explicit size for the string. See
1795L<perlfunc/pack>.
1796
f2cccb4c
KW
1797=for comment
1798The following are used in lib/diagnostics.t for testing two =items that
1799share the same description. Changes here need to be propagated to there
1800
6651ba0b
FC
1801=item Deep recursion on anonymous subroutine
1802
a0d0e21e
LW
1803=item Deep recursion on subroutine "%s"
1804
be771a83
GS
1805(W recursion) This subroutine has called itself (directly or indirectly)
1806100 times more than it has returned. This probably indicates an
1807infinite recursion, unless you're writing strange benchmark programs, in
1808which case it indicates something else.
a0d0e21e 1809
aad1d01f
NC
1810This threshold can be changed from 100, by recompiling the F<perl> binary,
1811setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1812
e0e4a6e3
FC
1813=item (?(DEFINE)....) does not allow branches in regex; marked by
1814S<<-- HERE> in m/%s/
bcb95744 1815
6903afa2 1816(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1817most likely cause of this error is that you left out a parenthesis inside
1818of the C<....> part.
1819
6e8a73f2 1820The S<<-- HERE> shows whereabouts in the regular expression the problem was
bcb95744
FC
1821discovered.
1822
62658f4d
PM
1823=item %s defines neither package nor VERSION--version check failed
1824
1825(F) You said something like "use Module 42" but in the Module file
1826there are neither package declarations nor a C<$VERSION>.
1827
36447869
FC
1828=item delete argument is index/value array slice, use array slice
1829
1830(F) You used index/value array slice syntax (C<%array[...]>) as
1831the argument to C<delete>. You probably meant C<@array[...]> with
1832an @ symbol instead.
1833
1834=item delete argument is key/value hash slice, use hash slice
1835
1836(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1837C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1838
0ffcbc25
FC
1839=item delete argument is not a HASH or ARRAY element or slice
1840
4a0af295 1841(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1842such as:
1843
1844 $foo{$bar}
1845 $ref->{"susie"}[12]
1846
1847or a hash or array slice, such as:
1848
1849 @foo[$bar, $baz, $xyzzy]
1850 @{$ref->[12]}{"susie", "queue"}
1851
fc36a67e
PP
1852=item Delimiter for here document is too long
1853
be771a83
GS
1854(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1855long for Perl to handle. You have to be seriously twisted to write code
1856that triggers this error.
fc36a67e 1857
6d3b25aa
RGS
1858=item Deprecated use of my() in false conditional
1859
fa816bf3
FC
1860(D deprecated) You used a declaration similar to C<my $x if 0>. There
1861has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1862not to be cleared at scope exit when its declaration includes a false
6903afa2 1863conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1864static variable. Since we intend to fix this bug, we don't want people
6903afa2 1865relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1866declaring the variable in a separate block outside the function, eg
36fb85f3 1867
6d3b25aa
RGS
1868 sub f { my $x if 0; return $x++ }
1869
1870becomes
1871
1872 { my $x; sub f { return $x++ } }
1873
ea9d9ebc 1874Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1875lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1876
1877 sub f { state $x; return $x++ }
1878
500ab966
RGS
1879=item DESTROY created new reference to dead object '%s'
1880
1881(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1882just being DESTROYed. Perl is confused, and prefers to abort rather
1883than to create a dangling reference.
500ab966 1884
3cdd684c
TP
1885=item Did not produce a valid header
1886
1887See Server error.
1888
6df41af2
GS
1889=item %s did not return a true value
1890
1891(F) A required (or used) file must return a true value to indicate that
1892it compiled correctly and ran its initialization code correctly. It's
1893traditional to end such a file with a "1;", though any true value would
1894do. See L<perlfunc/require>.
1895
cc507455 1896=item (Did you mean &%s instead?)
4633a7c4 1897
413ff9f6
FC
1898(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1899some such.
4633a7c4 1900
cc507455 1901=item (Did you mean "local" instead of "our"?)
33633739 1902
be771a83
GS
1903(W misc) Remember that "our" does not localize the declared global
1904variable. You have declared it again in the same lexical scope, which
1905seems superfluous.
33633739 1906
cc507455 1907=item (Did you mean $ or @ instead of %?)
a0d0e21e 1908
be771a83
GS
1909(W) You probably said %hash{$key} when you meant $hash{$key} or
1910@hash{@keys}. On the other hand, maybe you just meant %hash and got
1911carried away.
748a9306 1912
7e1af8bc 1913=item Died
5f05dabc
PP
1914
1915(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1916you called it with no args and C<$@> was empty.
5f05dabc 1917
3cdd684c
TP
1918=item Document contains no data
1919
1920See Server error.
1921
62658f4d
PM
1922=item %s does not define %s::VERSION--version check failed
1923
1924(F) You said something like "use Module 42" but the Module did not
943fc58e 1925define a C<$VERSION>.
62658f4d 1926
49704364
LW
1927=item '/' does not take a repeat count
1928
1929(F) You cannot put a repeat count of any kind right after the '/' code.
1930See L<perlfunc/pack>.
1931
95cb0d72
FC
1932=item Don't know how to get file name
1933
1934(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1935somehow called on another platform. This should not happen.
1936
4021c788 1937=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1938
1939(P) The internal handling of magical variables has been cursed.
1940
1941=item do_study: out of memory
1942
1943(P) This should have been caught by safemalloc() instead.
1944
6df41af2
GS
1945=item (Do you need to predeclare %s?)
1946
56da5a46
RGS
1947(S syntax) This is an educated guess made in conjunction with the message
1948"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1949name is being referenced that hasn't been declared yet. This may be
1950because of ordering problems in your file, or because of a missing
be771a83
GS
1951"sub", "package", "require", or "use" statement. If you're referencing
1952something that isn't defined yet, you don't actually have to define the
1953subroutine or package before the current location. You can use an empty
1954"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1955
ac206dc8
RGS
1956=item dump() better written as CORE::dump()
1957
1958(W misc) You used the obsolescent C<dump()> built-in function, without fully
1959qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1960
84d78eb7
YO
1961=item dump is not supported
1962
1963(F) Your machine doesn't support dump/undump.
1964
a0d0e21e
LW
1965=item Duplicate free() ignored
1966
be771a83
GS
1967(S malloc) An internal routine called free() on something that had
1968already been freed.
a0d0e21e 1969
1109a392
MHM
1970=item Duplicate modifier '%c' after '%c' in %s
1971
35f0cd76
FC
1972(W unpack) You have applied the same modifier more than once after a
1973type in a pack template. See L<perlfunc/pack>.
1109a392 1974
4633a7c4
LW
1975=item elseif should be elsif
1976
fa816bf3
FC
1977(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1978it's ugly. Your code will be interpreted as an attempt to call a method
1979named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1980unlikely to be what you want.
1981
e0e4a6e3 1982=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1983
af6f566e 1984(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1985described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1986a regular expression without specifying the property name.
ab13f0c7 1987
85ab1d1d 1988=item entering effective %s failed
5ff3f7a4 1989
85ab1d1d 1990(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1991effective uids or gids failed.
1992
c038024b
RGS
1993=item %ENV is aliased to %s
1994
1995(F) You're running under taint mode, and the C<%ENV> variable has been
1996aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1997program's environment. This is potentially insecure.
c038024b 1998
748a9306
LW
1999=item Error converting file specification %s
2000
5f05dabc 2001(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 2002specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
2003single form when it must operate on them directly. Either you've passed
2004an invalid file specification to Perl, or you've found a case the
2005conversion routines don't handle. Drat.
748a9306 2006
ad19ef22 2007=item Eval-group in insecure regular expression
e4d48cc9 2008
be771a83
GS
2009(F) Perl detected tainted data when trying to compile a regular
2010expression that contains the C<(?{ ... })> zero-width assertion, which
2011is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 2012
ad19ef22 2013=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 2014
be771a83
GS
2015(F) Perl tried to compile a regular expression containing the
2016C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
2017pattern contains interpolated values. Since that is a security risk,
2018it is not allowed. If you insist, you may still do this by using the
2019C<re 'eval'> pragma or by explicitly building the pattern from an
2020interpolated string at run time and using that in an eval(). See
2021L<perlre/(?{ code })>.
e4d48cc9 2022
ad19ef22 2023=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 2024
be771a83
GS
2025(F) A regular expression contained the C<(?{ ... })> zero-width
2026assertion, but that construct is only allowed when the C<use re 'eval'>
2027pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 2028
e0e4a6e3
FC
2029=item EVAL without pos change exceeded limit in regex; marked by
2030S<<-- HERE> in m/%s/
1a147d38
YO
2031
2032(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 2033any text. Restructure the pattern so that text is consumed.
1a147d38 2034
6e8a73f2 2035The S<<-- HERE> shows whereabouts in the regular expression the problem was
1a147d38
YO
2036discovered.
2037
fc36a67e
PP
2038=item Excessively long <> operator
2039
2040(F) The contents of a <> operator may not exceed the maximum size of a
2041Perl identifier. If you're just trying to glob a long list of
2042filenames, try using the glob() operator, or put the filenames into a
2043variable and glob that.
2044
ed9aa3b7
SG
2045=item exec? I'm not *that* kind of operating system
2046
af8bb25a 2047(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 2048OS. See L<perlport>.
ed9aa3b7 2049
fe13d51d 2050=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
2051
2052(F) The final summary message when a Perl compilation fails.
2053
0ffcbc25
FC
2054=item exists argument is not a HASH or ARRAY element or a subroutine
2055
4a0af295 2056(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
2057subroutine with an ampersand, such as:
2058
2059 $foo{$bar}
2060 $ref->{"susie"}[12]
2061 &do_something
2062
2063=item exists argument is not a subroutine name
2064
ccfc2567
FC
2065(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
2066and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 2067
a0d0e21e
LW
2068=item Exiting eval via %s
2069
be771a83
GS
2070(W exiting) You are exiting an eval by unconventional means, such as a
2071goto, or a loop control statement.
e476b1b5
GS
2072
2073=item Exiting format via %s
2074
9a2ff54b 2075(W exiting) You are exiting a format by unconventional means, such as a
be771a83 2076goto, or a loop control statement.
a0d0e21e 2077
0a753a76
PP
2078=item Exiting pseudo-block via %s
2079
be771a83
GS
2080(W exiting) You are exiting a rather special block construct (like a
2081sort block or subroutine) by unconventional means, such as a goto, or a
2082loop control statement. See L<perlfunc/sort>.
0a753a76 2083
a0d0e21e
LW
2084=item Exiting subroutine via %s
2085
be771a83
GS
2086(W exiting) You are exiting a subroutine by unconventional means, such
2087as a goto, or a loop control statement.
a0d0e21e
LW
2088
2089=item Exiting substitution via %s
2090
be771a83
GS
2091(W exiting) You are exiting a substitution by unconventional means, such
2092as a return, a goto, or a loop control statement.
a0d0e21e 2093
e0e4a6e3 2094=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 2095
675fa9ff 2096(F) You wrote something like
c608e803
KW
2097
2098 (?13
2099
2100to denote a capturing group of the form
2101L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
2102but omitted the C<")">.
2103
e0e4a6e3 2104=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 2105
8b6fbf55
FC
2106(F) The C<(?[...])> extended character class regular expression construct
2107only allows character classes (including character class escapes like
2108C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
2109containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
2110This allows a regular expression containing just C<(?[...])> to be
2111interpolated. If you see this error message, then you probably
2112have some other C<(?...)> construct inside your character class. See
2113L<perlrecharclass/Extended Bracketed Character Classes>.
2114
baabe3fb 2115=item Experimental aliasing via reference not enabled
1f8155a2 2116
baabe3fb 2117(F) To do aliasing via references, you must first enable the feature:
1f8155a2 2118
baabe3fb
FC
2119 no warnings "experimental::refaliasing";
2120 use feature "refaliasing";
1f8155a2
FC
2121 \$x = \$y;
2122
30d9c59b
Z
2123=item Experimental subroutine signatures not enabled
2124
2125(F) To use subroutine signatures, you must first enable them:
2126
caa35032 2127 no warnings "experimental::signatures";
30d9c59b
Z
2128 use feature "signatures";
2129 sub foo ($left, $right) { ... }
2130
b9234255 2131=item Experimental %s on scalar is now forbidden
26230909 2132
b9234255
AC
2133(F) An experimental feature added in Perl 5.14 allowed C<each>, C<keys>,
2134C<push>, C<pop>, C<shift>, C<splice>, C<unshift>, and C<values> to be called
26230909
AC
2135with a scalar argument. This experiment is considered unsuccessful, and has
2136been removed. The C<postderef> feature may meet your needs better.
2137
6da34ecb
FC
2138=item Experimental "%s" subs not enabled
2139
2140(F) To use lexical subs, you must first enable them:
2141
2142 no warnings 'experimental::lexical_subs';
2143 use feature 'lexical_subs';
2144 my sub foo { ... }
2145
7b8d334a
GS
2146=item Explicit blessing to '' (assuming package main)
2147
be771a83
GS
2148(W misc) You are blessing a reference to a zero length string. This has
2149the effect of blessing the reference into the package main. This is
2150usually not what you want. Consider providing a default target package,
2151e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2152
6df41af2
GS
2153=item %s: Expression syntax
2154
be771a83
GS
2155(A) You've accidentally run your script through B<csh> instead of Perl.
2156Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2157
2158=item %s failed--call queue aborted
2159
3c10abe3
AG
2160(F) An untrapped exception was raised while executing a UNITCHECK,
2161CHECK, INIT, or END subroutine. Processing of the remainder of the
2162queue of such routines has been prematurely ended.
6df41af2 2163
e0e4a6e3 2164=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2165
98d31c73 2166(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2167character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2168in your false range is interpreted as a literal "-". In a C<(?[...])>
2169construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2170the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2171the problem was discovered. See L<perlre>.
73b437c8 2172
1b1ee2ef 2173=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2174
be771a83
GS
2175(P) An error peculiar to VMS. Something untoward happened in a VMS
2176system service or RTL routine; Perl's exit status should provide more
2177details. The filename in "at %s" and the line number in "line %d" tell
2178you which section of the Perl source code is distressed.
a0d0e21e
LW
2179
2180=item fcntl is not implemented
2181
2182(F) Your machine apparently doesn't implement fcntl(). What is this, a
2183PDP-11 or something?
2184
22846ab4
AB
2185=item FETCHSIZE returned a negative value
2186
2187(F) A tied array claimed to have a negative number of elements, which
2188is not possible.
2189
f337b084
TH
2190=item Field too wide in 'u' format in pack
2191
d8b5cc61 2192(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2193which can't encode values above 63. So there is no point in asking for
2194a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2195C<u63> as the format.
f337b084 2196
af8c498a 2197=item Filehandle %s opened only for input
a0d0e21e 2198
6c8d78fb
HS
2199(W io) You tried to write on a read-only filehandle. If you intended
2200it to be a read-write filehandle, you needed to open it with "+<" or
2201"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2202write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2203
af8c498a 2204=item Filehandle %s opened only for output
a0d0e21e 2205
6c8d78fb
HS
2206(W io) You tried to read from a filehandle opened only for writing, If
2207you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2208with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2209read from the file, use "<". See L<perlfunc/open>. Another possibility
2210is that you attempted to open filedescriptor 0 (also known as STDIN) for
2211output (maybe you closed STDIN earlier?).
97828cef
RGS
2212
2213=item Filehandle %s reopened as %s only for input
2214
2215(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2216as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2217previously.
2218
2219=item Filehandle STDIN reopened as %s only for output
2220
2221(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2222as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2223
2224=item Final $ should be \$ or $name
2225
2226(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2227a literal dollar sign, or was meant to introduce a variable name that
2228happens to be missing. So you have to put either the backslash or the
2229name.
a0d0e21e 2230
56e90b21
GS
2231=item flock() on closed filehandle %s
2232
be771a83 2233(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2234some time before now. Check your control flow. flock() operates on
be771a83
GS
2235filehandles. Are you attempting to call flock() on a dirhandle by the
2236same name?
56e90b21 2237
6df41af2
GS
2238=item Format not terminated
2239
2240(F) A format must be terminated by a line with a solitary dot. Perl got
2241to the end of your file without finding such a line.
2242
a0d0e21e
LW
2243=item Format %s redefined
2244
e476b1b5 2245(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2246
2247 {
271595cc 2248 no warnings 'redefine';
a0d0e21e
LW
2249 eval "format NAME =...";
2250 }
2251
a0d0e21e
LW
2252=item Found = in conditional, should be ==
2253
e476b1b5 2254(W syntax) You said
a0d0e21e
LW
2255
2256 if ($foo = 123)
2257
2258when you meant
2259
2260 if ($foo == 123)
2261
2262(or something like that).
2263
6df41af2
GS
2264=item %s found where operator expected
2265
56da5a46
RGS
2266(S syntax) The Perl lexer knows whether to expect a term or an operator.
2267If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2268operator, it gives you this warning. Usually it indicates that an
2269operator or delimiter was omitted, such as a semicolon.
6df41af2 2270
a0d0e21e
LW
2271=item gdbm store returned %d, errno %d, key "%s"
2272
2273(S) A warning from the GDBM_File extension that a store failed.
2274
2275=item gethostent not implemented
2276
2277(F) Your C library apparently doesn't implement gethostent(), probably
2278because if it did, it'd feel morally obligated to return every hostname
2279on the Internet.
2280
69282e91 2281=item get%sname() on closed socket %s
a0d0e21e 2282
be771a83
GS
2283(W closed) You tried to get a socket or peer socket name on a closed
2284socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2285
748a9306
LW
2286=item getpwnam returned invalid UIC %#o for user "%s"
2287
2288(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2289C<getpwnam> operator returned an invalid UIC.
2290
6df41af2
GS
2291=item getsockopt() on closed socket %s
2292
be771a83
GS
2293(W closed) You tried to get a socket option on a closed socket. Did you
2294forget to check the return value of your socket() call? See
6df41af2
GS
2295L<perlfunc/getsockopt>.
2296
0f539b13
BF
2297=item given is experimental
2298
675fa9ff
FC
2299(S experimental::smartmatch) C<given> depends on smartmatch, which
2300is experimental, so its behavior may change or even be removed
2301in any future release of perl. See the explanation under
2302L<perlsyn/Experimental Details on given and when>.
0f539b13 2303
68567d27
FC
2304=item Global symbol "%s" requires explicit package name (did you forget to
2305declare "my %s"?)
6df41af2 2306
a4edf47d 2307(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2308that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2309declared beforehand using "our", or explicitly qualified to say
2310which package the global variable is in (using "::").
6df41af2 2311
e476b1b5
GS
2312=item glob failed (%s)
2313
5ead438e 2314(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2315for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2316pattern that caused the external program to fail and exit with a
be771a83 2317nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2318resulted in a coredump, this may also mean that your csh (C shell)
2319is broken. If so, you should change all of the csh-related variables
2320in config.sh: If you have tcsh, make the variables refer to it as
2321if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2322all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2323think csh is missing. In either case, after editing config.sh, run
75b44862 2324C<./Configure -S> and rebuild Perl.
e476b1b5 2325
a0d0e21e
LW
2326=item Glob not terminated
2327
2328(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2329a term, so it's looking for the corresponding right angle bracket, and
2330not finding it. Chances are you left some needed parentheses out
2331earlier in the line, and you really meant a "less than".
a0d0e21e 2332
b35b96b6
JH
2333=item gmtime(%f) failed
2334
2335(W overflow) You called C<gmtime> with a number that it could not handle:
2336too large, too small, or NaN. The returned value is C<undef>.
2337
bcd05b94 2338=item gmtime(%f) too large
8b56d6ff 2339
e9200be3 2340(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2341it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2342date. This warning is also triggered with NaN (the special
fc003d4b
MS
2343not-a-number value).
2344
bcd05b94 2345=item gmtime(%f) too small
fc003d4b 2346
e9200be3 2347(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2348it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2349
6df41af2 2350=item Got an error from DosAllocMem
a0d0e21e 2351
6df41af2
GS
2352(P) An error peculiar to OS/2. Most probably you're using an obsolete
2353version of Perl, and this should not happen anyway.
a0d0e21e
LW
2354
2355=item goto must have label
2356
2357(F) Unlike with "next" or "last", you're not allowed to goto an
2358unspecified destination. See L<perlfunc/goto>.
2359
6651ba0b
FC
2360=item Goto undefined subroutine%s
2361
2362(F) You tried to call a subroutine with C<goto &sub> syntax, but
2363the indicated subroutine hasn't been defined, or if it was, it
2364has since been undefined.
2365
6fbc9859 2366=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2367S<<-- HERE> in m/%s/
1f4f6bf1
YO
2368
2369(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2370they must start with a non-digit word character. A common cause of
2371this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2372
5a25739d
FC
2373=item ()-group starts with a count
2374
2375(F) A ()-group started with a count. A count is supposed to follow
2376something: a template character or a ()-group. See L<perlfunc/pack>.
2377
fe13d51d 2378=item %s had compilation errors.
6df41af2
GS
2379
2380(F) The final summary message when a C<perl -c> fails.
2381
a0d0e21e
LW
2382=item Had to create %s unexpectedly
2383
be771a83
GS
2384(S internal) A routine asked for a symbol from a symbol table that ought
2385to have existed already, but for some reason it didn't, and had to be
2386created on an emergency basis to prevent a core dump.
a0d0e21e 2387
6df41af2
GS
2388=item %s has too many errors
2389
2390(F) The parser has given up trying to parse the program after 10 errors.
2391Further error messages would likely be uninformative.
2392
cc4d09e1
KW
2393=item Having more than one /%c regexp modifier is deprecated
2394
2395(D deprecated, regexp) You used the indicated regular expression pattern
2396modifier at least twice in a string of modifiers. It is deprecated to
2397do this with this particular modifier, to allow future extensions to the
2398Perl language.
2399
61e61fbc
JH
2400=item Hexadecimal float: exponent overflow
2401
d8f2b442 2402(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2403than the floating point supports.
2404
2405=item Hexadecimal float: exponent underflow
2406
d8f2b442 2407(W overflow) The hexadecimal floating point has a smaller exponent
61e61fbc
JH
2408than the floating point supports.
2409
5488d373 2410=item Hexadecimal float: internal error (%s)
cf4f6003
JH
2411
2412(F) Something went horribly bad in hexadecimal float handling.
2413
61e61fbc
JH
2414=item Hexadecimal float: mantissa overflow
2415
2416(W overflow) The hexadecimal floating point literal had more bits in
2417the mantissa (the part between the 0x and the exponent, also known as
2418the fraction or the significand) than the floating point supports.
2419
40bca5ae
JH
2420=item Hexadecimal float: precision loss
2421
2422(W overflow) The hexadecimal floating point had internally more
2423digits than could be output. This can be caused by unsupported
2424long double formats, or by 64-bit integers not being available
2425(needed to retrieve the digits under some configurations).
2426
2427=item Hexadecimal float: unsupported long double format
2428
2429(F) You have configured Perl to use long doubles but
d8f2b442 2430the internals of the long double format are unknown;
40bca5ae
JH
2431therefore the hexadecimal float output is impossible.
2432
252aa082
JH
2433=item Hexadecimal number > 0xffffffff non-portable
2434
e476b1b5 2435(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2436(4294967295) and therefore non-portable between systems. See
2437L<perlport> for more on portability concerns.
252aa082 2438
8903cb82
PP
2439=item Identifier too long
2440
2441(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2442about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2443names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2444of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2445
e0e4a6e3
FC
2446=item Ignoring zero length \N{} in character class in regex; marked by
2447S<<-- HERE> in m/%s/
fc8cd66c 2448
f3ba6905 2449(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
0f44b2a5
FC
2450zero-length sequence. When such an escape is used in a character
2451class its behavior is not well defined. Check that the correct
2452escape has been used, and the correct charname handler is in scope.
fc8cd66c 2453
6df41af2 2454=item Illegal binary digit %s
f675dbe5 2455
6df41af2 2456(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2457
6df41af2 2458=item Illegal binary digit %s ignored
a0d0e21e 2459
be771a83
GS
2460(W digit) You may have tried to use a digit other than 0 or 1 in a
2461binary number. Interpretation of the binary number stopped before the
2462offending digit.
a0d0e21e 2463
6597eb22
FC
2464=item Illegal character after '_' in prototype for %s : %s
2465
e4d150f1
FC
2466(W illegalproto) An illegal character was found in a prototype
2467declaration. The '_' in a prototype must be followed by a ';',
2468indicating the rest of the parameters are optional, or one of '@'
2469or '%', since those two will accept 0 or more final parameters.
6597eb22 2470
78d0fecf 2471=item Illegal character \%o (carriage return)
4fdae800 2472
d5898338 2473(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2474would any other whitespace, which means you should never see this error
2475when Perl was built using standard options. For some reason, your
2476version of Perl appears to have been built without this support. Talk
2477to your Perl administrator.
4fdae800 2478
d37a9538
ST
2479=item Illegal character in prototype for %s : %s
2480
197afce1 2481(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2482Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2483Perhaps you were trying to write a subroutine signature but didn't enable
2484that feature first (C<use feature 'signatures'>), so your signature was
2485instead interpreted as a bad prototype.
d37a9538 2486
904d85c5
RGS
2487=item Illegal declaration of anonymous subroutine
2488
2489(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2490you must always specify a block of code. See L<perlsub>.
904d85c5 2491
8e742a20
MHM
2492=item Illegal declaration of subroutine %s
2493
6903afa2 2494(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2495
a0d0e21e
LW
2496=item Illegal division by zero
2497
be771a83
GS
2498(F) You tried to divide a number by 0. Either something was wrong in
2499your logic, or you need to put a conditional in to guard against
2500meaningless input.
a0d0e21e 2501
6df41af2
GS
2502=item Illegal hexadecimal digit %s ignored
2503
be771a83
GS
2504(W digit) You may have tried to use a character other than 0 - 9 or
2505A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2506number stopped before the illegal character.
6df41af2 2507
a0d0e21e
LW
2508=item Illegal modulus zero
2509
be771a83
GS
2510(F) You tried to divide a number by 0 to get the remainder. Most
2511numbers don't take to this kindly.
a0d0e21e 2512
6df41af2 2513=item Illegal number of bits in vec
399388f4 2514
6df41af2
GS
2515(F) The number of bits in vec() (the third argument) must be a power of
2516two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2517
2518=item Illegal octal digit %s
a0d0e21e 2519
d1be9408 2520(F) You used an 8 or 9 in an octal number.
a0d0e21e 2521
399388f4 2522=item Illegal octal digit %s ignored
748a9306 2523
d1be9408 2524(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2525Interpretation of the octal number stopped before the 8 or 9.
748a9306 2526
e0e4a6e3 2527=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2528
675fa9ff 2529(F) You wrote something like
c608e803
KW
2530
2531 (?+foo)
2532
2533The C<"+"> is valid only when followed by digits, indicating a
2534capturing group. See
2535L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2536
375ed12a
JH
2537=item Illegal suidscript
2538
2539(F) The script run under suidperl was somehow illegal.
2540
fe13d51d 2541=item Illegal switch in PERL5OPT: -%c
6ff81951 2542
6df41af2 2543(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2544following switches: B<-[CDIMUdmtw]>.
6ff81951 2545
6df41af2 2546=item Ill-formed CRTL environ value "%s"
81e118e0 2547
75b44862 2548(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2549internal environ array, and encountered an element without the C<=>
2550delimiter used to separate keys from values. The element is ignored.
09bef843 2551
6df41af2 2552=item Ill-formed message in prime_env_iter: |%s|
54310121 2553
be771a83
GS
2554(W internal) A warning peculiar to VMS. Perl tried to read a logical
2555name or CLI symbol definition when preparing to iterate over %ENV, and
2556didn't see the expected delimiter between key and value, so the line was
2557ignored.
54310121 2558
6df41af2 2559=item (in cleanup) %s
9607fc9c 2560
be771a83
GS
2561(W misc) This prefix usually indicates that a DESTROY() method raised
2562the indicated exception. Since destructors are usually called by the
2563system at arbitrary points during execution, and often a vast number of
2564times, the warning is issued only once for any number of failures that
2565would otherwise result in the same message being repeated.
6df41af2 2566
be771a83
GS
2567Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2568also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2569
e0e4a6e3
FC
2570=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2571in m/%s/
0d0b4b3b 2572
675fa9ff 2573(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2574expression inside the construct was completely empty, or if there are
2575too many or few operands for the number of operators. Perl is not smart
2576enough to give you a more precise indication as to what is wrong.
2577
6fbc9859
MH
2578=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2579parent '%s'
2c7d6b9c
RGS
2580
2581(F) The method resolution order (MRO) of the given class is not
2582C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2583documentation in L<mro> for more information.
2584
979699d9
JH
2585=item In EBCDIC the v-string components cannot exceed 2147483647
2586
2587(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2588Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2589encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2590
6a2ed79a 2591=item Infinite recursion in regex
1a147d38
YO
2592
2593(F) You used a pattern that references itself without consuming any input
6903afa2 2594text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2595either consume text or fail.
2596
6dbe9451
NC
2597=item Initialization of state variables in list context currently forbidden
2598
6903afa2
FC
2599(F) Currently the implementation of "state" only permits the
2600initialization of scalar variables in scalar context. Re-write
2601C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2602context. Constructions such as C<state (@a) = foo()> will be
2603supported in a future perl release.
6dbe9451 2604
2186f873
FC
2605=item %%s[%s] in scalar context better written as $%s[%s]
2606
2607(W syntax) In scalar context, you've used an array index/value slice
2608(indicated by %) to select a single element of an array. Generally
2609it's better to ask for a scalar value (indicated by $). The difference
2610is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2611returns and when evaluating its argument, while C<%foo[&bar]> provides
2612a list context to its subscript, which can do weird things if you're
2613expecting only one subscript. When called in list context, it also
2614returns the index (what C<&bar> returns) in addition to the value.
2615
2616=item %%s{%s} in scalar context better written as $%s{%s}
2617
2618(W syntax) In scalar context, you've used a hash key/value slice
2619(indicated by %) to select a single element of a hash. Generally it's
2620better to ask for a scalar value (indicated by $). The difference
2621is that C<$foo{&bar}> always behaves like a scalar, both in the value
2622it returns and when evaluating its argument, while C<@foo{&bar}> and
2623provides a list context to its subscript, which can do weird things
2624if you're expecting only one subscript. When called in list context,
2625it also returns the key in addition to the value.
2626
fb10a8a7
TC
2627=item %s() is deprecated on :utf8 handles
2628
2629(W deprecated) The sysread(), recv(), syswrite() and send() operators
2630are deprecated on handles that have the C<:utf8> layer, either
2631explicitly, or implicitly, eg., with the C<:encoding(UTF-16LE)> layer.
2632
2633Both sysread() and recv() currently use only the C<:utf8> flag for the
2634stream, ignoring the actual layers. Since sysread() and recv() do no
2635UTF-8 validation they can end up creating invalidly encoded scalars.
2636
2637Similarly, syswrite() and send() use only the C<:utf8> flag, otherwise
2638ignoring any layers. If the flag is set, both write the value UTF-8
2639encoded, even if the layer is some different encoding, such as the
2640example above.
2641
2642Ideally, all of these operators would completely ignore the C<:utf8>
2643state, working only with bytes, but this would result in silently
2644breaking existing code. To avoid this a future version of perl will
2645throw an exception when any of sysread(), recv(), syswrite() or send()
2646are called on handle with the C<:utf8> layer.
2647
a0d0e21e
LW
2648=item Insecure dependency in %s
2649
8b1a09fc 2650(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2651The tainting mechanism is turned on when you're running setuid or
2652setgid, or when you specify B<-T> to turn it on explicitly. The
2653tainting mechanism labels all data that's derived directly or indirectly
2654from the user, who is considered to be unworthy of your trust. If any
2655such data is used in a "dangerous" operation, you get this error. See
2656L<perlsec> for more information.
a0d0e21e
LW
2657
2658=item Insecure directory in %s
2659
be771a83
GS
2660(F) You can't use system(), exec(), or a piped open in a setuid or
2661setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2662the world. Also, the PATH must not contain any relative directory.
2663See L<perlsec>.
a0d0e21e 2664
62f468fc 2665=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2666
2667(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2668setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2669C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2670supplied (or potentially supplied) by the user. The script must set
2671the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2672
0e9be77f
DM
2673=item Insecure user-defined property %s
2674
2675(F) Perl detected tainted data when trying to compile a regular
2676expression that contains a call to a user-defined character property
2677function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2678See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2679
b9ef414d
FC
2680=item Integer overflow in format string for %s
2681
2682(F) The indexes and widths specified in the format string of C<printf()>
2683or C<sprintf()> are too large. The numbers must not overflow the size of
2684integers for your architecture.
2685
a7ae9550
GS
2686=item Integer overflow in %s number
2687
35928bc5 2688(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2689either as a literal or as an argument to hex() or oct() is too big for
2690your architecture, and has been converted to a floating point number.
2691On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2692representable without overflow is 0xFFFFFFFF, 037777777777, or
26930b11111111111111111111111111111111 respectively. Note that Perl
2694transparently promotes all numbers to a floating point representation
2695internally--subject to loss of precision errors in subsequent
2696operations.
bbce6d69 2697
fc89ca81
FC
2698=item Integer overflow in srand
2699
2700(S overflow) The number you have passed to srand is too big to fit
2701in your architecture's integer representation. The number has been
2702replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2703architectures). This means you may be getting less randomness than
2704you expect, because different random seeds above the maximum will
2705return the same sequence of random numbers.
2706
46314c13
JP
2707=item Integer overflow in version
2708
18da5252
FC
2709=item Integer overflow in version %d
2710
784d71ed
FC
2711(W overflow) Some portion of a version initialization is too large for
2712the size of integers for your architecture. This is not a warning
f084e84f 2713because there is no rational reason for a version to try and use an
784d71ed
FC
2714element larger than typically 2**32. This is usually caused by trying
2715to use some odd mathematical operation as a version, like 100/9.
46314c13 2716
e0e4a6e3 2717=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2718
2719(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2720The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2721discovered.
2722
748a9306
LW
2723=item Internal inconsistency in tracking vforks
2724
be771a83
GS
2725(S) A warning peculiar to VMS. Perl keeps track of the number of times
2726you've called C<fork> and C<exec>, to determine whether the current call
2727to C<exec> should affect the current script or a subprocess (see
2728L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2729Perl is making a guess and treating this C<exec> as a request to
2730terminate the Perl script and execute the specified command.
748a9306 2731
870978ae
FC
2732=item internal %<num>p might conflict with future printf extensions
2733
2734(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2735formatting follows a slightly different set of rules when called from
2736C or XS code. Specifically, formats consisting of digits followed
2737by "p" (e.g., "%7p") are reserved for future use. If you see this
2738message, then an XS module tried to call that routine with one such
2739reserved format.
2740
e0e4a6e3 2741=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2742
fa816bf3 2743(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2744S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2745discovered.
a0d0e21e 2746
6df41af2
GS
2747=item %s (...) interpreted as function
2748
75b44862 2749(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2750followed by parentheses turns into a function, with all the list
64977eb6 2751operators arguments found inside the parentheses. See
13a2d996 2752L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2753
f51551f7
FC
2754=item In '(?...)', the '(' and '?' must be adjacent in regex;
2755marked by S<<-- HERE> in m/%s/
2756
2757(F) The two-character sequence C<"(?"> in this context in a regular
2758expression pattern should be an indivisible token, with nothing
2759intervening between the C<"("> and the C<"?">, but you separated them
2760with whitespace.
2761
09bef843
SB
2762=item Invalid %s attribute: %s
2763
a4a4c9e2 2764(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2765by Perl or by a user-supplied handler. See L<attributes>.
2766
2767=item Invalid %s attributes: %s
2768
a4a4c9e2 2769(F) The indicated attributes for a subroutine or variable were not
be771a83 2770recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2771
e0e4a6e3
FC
2772=item Invalid character in charnames alias definition; marked by
2773S<<-- HERE> in '%s
225fb84f
KW
2774
2775(F) You tried to create a custom alias for a character name, with
2776the C<:alias> option to C<use charnames> and the specified character in
2777the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2778
c8028aa6
TC
2779=item Invalid \0 character in %s for %s: %s\0%s
2780
fa3234e3
FC
2781(W syscalls) Embedded \0 characters in pathnames or other system call
2782arguments produce a warning as of 5.20. The parts after the \0 were
2783formerly ignored by system calls.
c8028aa6 2784
e0e4a6e3 2785=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2786
2787(F) Only certain characters are valid for character names. The
2788indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2789
c635e13b
PP
2790=item Invalid conversion in %s: "%s"
2791
be771a83
GS
2792(W printf) Perl does not understand the given format conversion. See
2793L<perlfunc/sprintf>.
c635e13b 2794
e0e4a6e3
FC
2795=item Invalid escape in the specified encoding in regex; marked by
2796S<<-- HERE> in m/%s/
9e08bc66 2797
98d31c73 2798(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2799didn't correspond to a single character through the conversion
2800from the encoding specified by the encoding pragma.
98d31c73
FC
2801The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2802instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2803The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2804escape was discovered.
2805
8149aa9f
FC
2806=item Invalid hexadecimal number in \N{U+...}
2807
e0e4a6e3
FC
2808=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2809S<<-- HERE> in m/%s/
aec0ef10 2810
8149aa9f 2811(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2812number. Either it is empty, or you tried to use a character other than
28130 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2814
6651ba0b
FC
2815=item Invalid module name %s with -%c option: contains single ':'
2816
2817(F) The module argument to perl's B<-m> and B<-M> command-line options
2818cannot contain single colons in the module name, but only in the
2819arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2820B<-MFoo:Bar=baz> is not.
2821
2c7d6b9c
RGS
2822=item Invalid mro name: '%s'
2823
162a3e34
FC
2824(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2825where C<foo> is not a valid method resolution order (MRO). Currently,
2826the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2827a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2828
40e4140b
FC
2829=item Invalid negative number (%s) in chr
2830
2831(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2832not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2833character (U+FFFD).
2834
6651ba0b
FC
2835=item invalid option -D%c, use -D'' to see choices
2836
8ff21bfe
FC
2837(S debugging) Perl was called with invalid debugger flags. Call perl
2838with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2839See also L<perlrun/-Dletters>.
6651ba0b 2840
6e8a73f2 2841=item Invalid quantifier in {,} in regex; marked by S<<-- HERE> in m/%s/
35cd12d1
HS
2842
2843(F) The pattern looks like a {min,max} quantifier, but the min or max
2844could not be parsed as a valid number - either it has leading zeroes,
2845or it represents too big a number to cope with. The S<<-- HERE> shows
2846where in the regular expression the problem was discovered. See L<perlre>.
2847
e0e4a6e3 2848=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2849
2850(F) The range specified in a character class had a minimum character
7253e4e3
RK
2851greater than the maximum character. One possibility is that you forgot the
2852C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2853up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2854problem was discovered. See L<perlre>.
6df41af2 2855
d1573ac7 2856=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2857
2858(F) The range specified in the tr/// or y/// operator had a minimum
2859character greater than the maximum character. See L<perlop>.
2860
09bef843
SB
2861=item Invalid separator character %s in attribute list
2862
0120eecf 2863(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2864elements of an attribute list. If the previous attribute had a
2865parenthesised parameter list, perhaps that list was terminated too soon.
2866See L<attributes>.
09bef843 2867
b4581f09
JH
2868=item Invalid separator character %s in PerlIO layer specification %s
2869
2bfc5f71
FC
2870(W layer) When pushing layers onto the Perl I/O system, something other
2871than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2872If the previous attribute had a parenthesised parameter list, perhaps that
2873list was terminated too soon.
2874
2c86d456
DG
2875=item Invalid strict version format (%s)
2876
fa816bf3 2877(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2878A "strict" version number is a positive decimal number (integer or
2879decimal-fraction) without exponentiation or else a dotted-decimal
2880v-string with a leading 'v' character and at least three components.
a6485a24 2881The parenthesized text indicates which criteria were not met.
2c86d456
DG
2882See the L<version> module for more details on allowed version formats.
2883
49704364 2884=item Invalid type '%s' in %s
96e4d5b1 2885
49704364
LW
2886(F) The given character is not a valid pack or unpack type.
2887See L<perlfunc/pack>.
6728c851 2888
49704364 2889(W) The given character is not a valid pack or unpack type but used to be
75b44862 2890silently ignored.
96e4d5b1 2891
2c86d456
DG
2892=item Invalid version format (%s)
2893
fa816bf3 2894(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2895A "lax" version number is a positive decimal number (integer or
2896decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2897v-string. If the v-string has fewer than three components, it
2898must have a leading 'v' character. Otherwise, the leading 'v' is
2899optional. Both decimal and dotted-decimal versions may have a
2900trailing "alpha" component separated by an underscore character
2901after a fractional or dotted-decimal component. The parenthesized
2902text indicates which criteria were not met. See the L<version> module
2903for more details on allowed version formats.
46314c13 2904
798ae1b7
DG
2905=item Invalid version object
2906
fa816bf3
FC
2907(F) The internal structure of the version object was invalid.
2908Perhaps the internals were modified directly in some way or
2909an arbitrary reference was blessed into the "version" class.
798ae1b7 2910
cd209d9d 2911=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2912marked by S<<-- HERE> in m/%s/
675fa9ff 2913
cd209d9d 2914(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2915this context in a regular expression pattern should be an
2916indivisible token, with nothing intervening between the C<"(">
cd209d9d 2917and the C<"*">, but you separated them.
675fa9ff 2918
a0d0e21e
LW
2919=item ioctl is not implemented
2920
2921(F) Your machine apparently doesn't implement ioctl(), which is pretty
2922strange for a machine that supports C.
2923
c289d2f7
JH
2924=item ioctl() on unopened %s
2925
2926(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2927Check your control flow and number of arguments.
c289d2f7 2928
fe13d51d 2929=item IO layers (like '%s') unavailable
363c40c4
SB
2930
2931(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2932you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2933with 'useperlio'.
2934
80cbd5ad
JH
2935=item IO::Socket::atmark not implemented on this architecture
2936
2937(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2938neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2939
6e8a73f2 2940=item '%s' is an unknown bound type in regex; marked by S<<-- HERE> in m/%s/
64935bc6
KW
2941
2942(F) You used C<\b{...}> or C<\B{...}> and the C<...> is not known to
2943Perl. The current valid ones are given in
2944L<perlrebackslash/\b{}, \b, \B{}, \B>.
2945
6e8a73f2 2946=item "%s" is more clearly written simply as "%s" in regex; marked by S<<-- HERE> in m/%s/
acdfc3b6
KW
2947
2948(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
2949
2950You specified a character that has the given plainer way of writing it,
2951and which is also portable to platforms running with different character
2952sets.
2953
4f650b80 2954=item $* is no longer supported
b4581f09 2955
4f650b80 2956(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2957perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2958previous versions of perl the use of C<$*> enabled or disabled multi-line
2959matching within a string.
4fd19576
B
2960
2961Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2962modifiers. You can enable C</m> for a lexical scope (even a whole file)
2963with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2964then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2965
8ae1fe26
RGS
2966=item $# is no longer supported
2967
a58ac25e 2968(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2969perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2970should use the printf/sprintf functions instead.
8ae1fe26 2971
ccf3535a 2972=item '%s' is not a code reference
6ad11d81 2973
6903afa2
FC
2974(W overload) The second (fourth, sixth, ...) argument of
2975overload::constant needs to be a code reference. Either
2976an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2977
ccf3535a 2978=item '%s' is not an overloadable type
6ad11d81 2979
04a80ee0
RGS
2980(W overload) You tried to overload a constant type the overload package is
2981unaware of.
6ad11d81 2982
5a25739d
FC
2983=item -i used with no filenames on the command line, reading from STDIN
2984
2985(S inplace) The C<-i> option was passed on the command line, indicating
2986that the script is intended to edit files in place, but no files were
2987given. This is usually a mistake, since editing STDIN in place doesn't
2988make sense, and can be confusing because it can make perl look like
2989it is hanging when it is really just trying to read from STDIN. You
2990should either pass a filename to edit, or remove C<-i> from the command
2991line. See L<perlrun> for more details.
2992
aec0ef10 2993=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2994
2995(P) The regular expression parser is confused.
2996
2997=item Label not found for "last %s"
2998
be771a83
GS
2999(F) You named a loop to break out of, but you're not currently in a loop
3000of that name, not even if you count where you were called from. See
3001L<perlfunc/last>.
a0d0e21e
LW
3002
3003=item Label not found for "next %s"
3004
3005(F) You named a loop to continue, but you're not currently in a loop of
3006that name, not even if you count where you were called from. See
3007L<perlfunc/last>.
3008
3009=item Label not found for "redo %s"
3010
3011(F) You named a loop to restart, but you're not currently in a loop of
3012that name, not even if you count where you were called from. See
3013L<perlfunc/last>.
3014
85ab1d1d 3015=item leaving effective %s failed
5ff3f7a4 3016
85ab1d1d 3017(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
3018effective uids or gids failed.
3019
49704364
LW
3020=item length/code after end of string in unpack
3021
d7f8936a 3022(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
3023length/code combination tried to obtain more data. This results in
3024an undefined value for the length. See L<perlfunc/pack>.
49704364 3025
25e26107 3026=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 3027
0d46a4e7
FC
3028(W syntax) You used length() on either an array or a hash when you
3029probably wanted a count of the items.
e508c8a4
MH
3030
3031Array size can be obtained by doing:
3032
3033 scalar(@array);
3034
3035The number of items in a hash can be obtained by doing:
3036
3037 scalar(keys %hash);
3038
f0e67a1d
Z
3039=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
3040
d4fe7078
RS
3041(F) An extension is attempting to insert text into the current parse
3042(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
3043couldn't be part of the current input. This is an inherent pitfall
3044of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 3045it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
3046
3047=item Lexing code internal error (%s)
3048
3049(F) Lexing code supplied by an extension violated the lexer's API in a
3050detectable way.
3051
69282e91 3052=item listen() on closed socket %s
a0d0e21e 3053
be771a83
GS
3054(W closed) You tried to do a listen on a closed socket. Did you forget
3055to check the return value of your socket() call? See
3056L<perlfunc/listen>.
a0d0e21e 3057
6651ba0b
FC
3058=item List form of piped open not implemented
3059
3060(F) On some platforms, notably Windows, the three-or-more-arguments
3061form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
3062Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
3063
dc6bb7ba
FC
3064=item %s: loadable library and perl binaries are mismatched (got handshake key %p, needed %p)
3065
3066(P) A dynamic loading library C<.so> or C<.dll> was being loaded into the
3067process that was built against a different build of perl than the
3068said library was compiled against. Reinstalling the XS module will
3069likely fix this error.
3070
8c6180a9
KW
3071=item Locale '%s' may not work well.%s
3072
780fcc9f 3073(W locale) You are using the named locale, which is a non-UTF-8 one, and
dae67c56
KW
3074which perl has determined is not fully compatible with what it can
3075handle. The second C<%s> gives a reason.
8c6180a9
KW
3076
3077By far the most common reason is that the locale has characters in it
3078that are represented by more than one byte. The only such locales that
3079Perl can handle are the UTF-8 locales. Most likely the specified locale
3080is a non-UTF-8 one for an East Asian language such as Chinese or
3081Japanese. If the locale is a superset of ASCII, the ASCII portion of it
780fcc9f 3082may work in Perl.
8c6180a9
KW
3083
3084Some essentially obsolete locales that aren't supersets of ASCII, mainly
3085those in ISO 646 or other 7-bit locales, such as ASMO 449, can also have
3086problems, depending on what portions of the ASCII character set get
3087changed by the locale and are also used by the program.
3088The warning message lists the determinable conflicting characters.
3089
780fcc9f
KW
3090Note that not all incompatibilities are found.
3091
3092If this happens to you, there's not much you can do except switch to use a
3093different locale or use L<Encode> to translate from the locale into
3094UTF-8; if that's impracticable, you have been warned that some things
3095may break.
3096
3097This message is output once each time a bad locale is switched into
3098within the scope of C<S<use locale>>, or on the first possibly-affected
3099operation if the C<S<use locale>> inherits a bad one. It is not raised
3100for any operations from the L<POSIX> module.
3101
a2162cd9
FC
3102=item localtime(%f) failed
3103
3104(W overflow) You called C<localtime> with a number that it could not handle:
3105too large, too small, or NaN. The returned value is C<undef>.
3106
3107=item localtime(%f) too large
3108
3109(W overflow) You called C<localtime> with a number that was larger
3110than it can reliably handle and C<localtime> probably returned the
3111wrong date. This warning is also triggered with NaN (the special
3112not-a-number value).
3113
3114=item localtime(%f) too small
3115
3116(W overflow) You called C<localtime> with a number that was smaller
3117than it can reliably handle and C<localtime> probably returned the
3118wrong date.
3119
58e23c8d 3120=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
3121
3122(F) There is currently a limit on the length of string which lookbehind can
6903afa2 3123handle. This restriction may be eased in a future release.
2e50fd82 3124
b88df990
NC
3125=item Lost precision when %s %f by 1
3126
e63e8a91
FC
3127(W imprecision) The value you attempted to increment or decrement by one
3128is too large for the underlying floating point representation to store
3129accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
3130warning because it has already switched from integers to floating point
3131when values are too large for integers, and now even floating point is
3132insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 3133
93fad930 3134=item lstat() on filehandle%s
2f7da168
RK
3135
3136(W io) You tried to do an lstat on a filehandle. What did you mean
3137by that? lstat() makes sense only on filenames. (Perl did a fstat()
3138instead on the filehandle.)
3139
345d70e3 3140=item lvalue attribute %s already-defined subroutine
bb3abb05 3141
345d70e3
FC
3142(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
3143attribute on or off on a Perl subroutine that is already defined
3144does not always work properly. It may or may not do what you
3145want, depending on what code is inside the subroutine, with exact
3146details subject to change between Perl versions. Only do this
3147if you really know what you are doing.
bb3abb05 3148
885ef6f5
GG
3149=item lvalue attribute ignored after the subroutine has been defined
3150
345d70e3
FC
3151(W misc) Using the C<:lvalue> declarative syntax to make a Perl
3152subroutine an lvalue subroutine after it has been defined is
3153not permitted. To make the subroutine an lvalue subroutine,
3154add the lvalue attribute to the definition, or put the C<sub
3155foo :lvalue;> declaration before the definition.
3156
3157See also L<attributes.pm|attributes>.
885ef6f5 3158
6f1b3ab0
FC
3159=item Magical list constants are not supported
3160
3161(F) You assigned a magical array to a stash element, and then tried
3162to use the subroutine from the same slot. You are asking Perl to do
3163something it cannot do, details subject to change between Perl versions.
3164
2db62bbc 3165=item Malformed integer in [] in pack
49704364 3166
2db62bbc 3167(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
3168are permitted. See L<perlfunc/pack>.
3169
3170=item Malformed integer in [] in unpack
3171
2db62bbc 3172(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
3173are permitted. See L<perlfunc/pack>.
3174
6df41af2
GS
3175=item Malformed PERLLIB_PREFIX
3176
3177(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
3178
3179 prefix1;prefix2
3180
3181or
6df41af2
GS
3182 prefix1 prefix2
3183
be771a83
GS
3184with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
3185a builtin library search path, prefix2 is substituted. The error may
3186appear if components are not found, or are too long. See
fecfaeb8 3187"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 3188
2f758a16
ST
3189=item Malformed prototype for %s: %s
3190
d37a9538
ST
3191(F) You tried to use a function with a malformed prototype. The
3192syntax of function prototypes is given a brief compile-time check for
3193obvious errors like invalid characters. A more rigorous check is run
3194when the function is called.
30d9c59b
Z
3195Perhaps the function's author was trying to write a subroutine signature
3196but didn't enable that feature first (C<use feature 'signatures'>),
3197so the signature was instead interpreted as a bad prototype.
2f758a16 3198
ba210ebe
JH
3199=item Malformed UTF-8 character (%s)
3200
4d6f11e5 3201(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 3202encoding rules, even though it had the UTF8 flag on.
ba210ebe 3203
2575c402
JW
3204One possible cause is that you set the UTF8 flag yourself for data that
3205you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 32068-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
3207
3208If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
3209sequences are handled gracefully, but if you use C<:utf8>, the flag is
3210set without validating the data, possibly resulting in this error
3211message.
3212
3213See also L<Encode/"Handling Malformed Data">.
901b21bf 3214
107160e2
KW
3215=item Malformed UTF-8 character immediately after '%s'
3216
3217(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
3218encoding rules. The message prints out the properly encoded characters
3219just before the first bad one. If C<utf8> warnings are enabled, a
3220warning is generated that gives more details about the type of
3221malformation.
3222
bde9e88d 3223=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
3224
3225(F) The charnames handler returned malformed UTF-8.
3226
4a5d3a93
FC
3227=item Malformed UTF-8 string in '%c' format in unpack
3228
3229(F) You tried to unpack something that didn't comply with UTF-8 encoding
3230rules and perl was unable to guess how to make more progress.
3231
f337b084
TH
3232=item Malformed UTF-8 string in pack
3233
3234(F) You tried to pack something that didn't comply with UTF-8 encoding
3235rules and perl was unable to guess how to make more progress.
3236
3237=item Malformed UTF-8 string in unpack
3238
3239(F) You tried to unpack something that didn't comply with UTF-8 encoding
3240rules and perl was unable to guess how to make more progress.
3241
4a5d3a93 3242=item Malformed UTF-16 surrogate
f337b084 3243
4a5d3a93
FC
3244(F) Perl thought it was reading UTF-16 encoded character data but while
3245doing it Perl met a malformed Unicode surrogate.
3246
30d9c59b
Z
3247=item Mandatory parameter follows optional parameter
3248
3249(F) In a subroutine signature, you wrote something like "$a = undef,
3250$b", making an earlier parameter optional and a later one mandatory.
3251Parameters are filled from left to right, so it's impossible for the
3252caller to omit an earlier one and pass a later one. If you want to act
3253as if the parameters are filled from right to left, declare the rightmost
3254optional and then shuffle the parameters around in the subroutine's body.
3255
2d88a86a
KW
3256=item Matched non-Unicode code point 0x%X against Unicode property; may
3257not be portable
3258
3259(S non_unicode) Perl allows strings to contain a superset of
3260Unicode code points; each code point may be as large as what is storable
3261in an unsigned integer on your system, but these may not be accepted by
3262other languages/systems. This message occurs when you matched a string
3263containing such a code point against a regular expression pattern, and
3264the code point was matched against a Unicode property, C<\p{...}> or
3265C<\P{...}>. Unicode properties are only defined on Unicode code points,
3266so the result of this match is undefined by Unicode, but Perl (starting
3267in v5.20) treats non-Unicode code points as if they were typical
3268unassigned Unicode ones, and matched this one accordingly. Whether a
3269given property matches these code points or not is specified in
3270L<perluniprops/Properties accessible through \p{} and \P{}>.
3271
3272This message is suppressed (unless it has been made fatal) if it is
3273immaterial to the results of the match if the code point is Unicode or
3274not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
3275the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
3276Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
3277every code point except these 22.)
3278
3279Getting this message indicates that the outcome of the match arguably
3280should have been the opposite of what actually happened. If you think
3281that is the case, you may wish to make the C<non_unicode> warnings
3282category fatal; if you agree with Perl's decision, you may wish to turn
3283off this category.
3284
3285See L<perlunicode/Beyond Unicode code points> for more information.
3286
e0e4a6e3
FC
3287=item %s matches null string many times in regex; marked by S<<-- HERE> in
3288m/%s/
4a5d3a93
FC
3289
3290(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 3291regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 3292shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 3293See L<perlre>.
f337b084 3294
de42a5a9 3295=item Maximal count of pending signals (%u) exceeded
2563cec5 3296
6903afa2 3297(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
3298usually indicates that your operating system tried to deliver signals
3299too fast (with a very high priority), starving the perl process from
3300resources it would need to reach a point where it can process signals
6903afa2 3301safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 3302
25f58aea
PN
3303=item "%s" may clash with future reserved word
3304
3305(W) This warning may be due to running a perl5 script through a perl4
3306interpreter, especially if the word that is being warned about is
3307"use" or "my".
3308
0d2487cd 3309=item '%' may not be used in pack
6df41af2
GS
3310
3311(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
3312checksumming process loses information, and you can't go the other way.
3313See L<perlfunc/unpack>.
6df41af2 3314
a0d0e21e
LW
3315=item Method for operation %s not found in package %s during blessing
3316
3317(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 3318doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 3319
3cdd684c
TP
3320=item Method %s not permitted
3321
3322See Server error.
3323
a0d0e21e
LW
3324=item Might be a runaway multi-line %s string starting on line %d
3325
3326(S) An advisory indicating that the previous error may have been caused
3327by a missing delimiter on a string or pattern, because it eventually
3328ended earlier on the current line.
3329
3330=item Misplaced _ in number
3331
d4ced10d
JH
3332(W syntax) An underscore (underbar) in a numeric constant did not
3333separate two digits.
a0d0e21e 3334
7baa4690
HS
3335=item Missing argument in %s
3336
3664866e
AB
3337(W missing) You called a function with fewer arguments than other
3338arguments you supplied indicated would be needed.
3339
3340Currently only emitted when a printf-type format required more
3341arguments than were supplied, but might be used in the future for
3342other cases where we can statically determine that arguments to
3343functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3344
9e81e6a1
RGS
3345=item Missing argument to -%c
3346
3347(F) The argument to the indicated command line switch must follow
3348immediately after the switch, without intervening spaces.
3349
ff3f963a 3350=item Missing braces on \N{}
423cee85 3351
e0e4a6e3 3352=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3353
4a2d328f 3354(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3355double-quotish context. This can also happen when there is a space
3356(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3357This modifier does not change the requirement that the brace immediately
3358follow the C<\N>.
423cee85 3359
f0a2b745
KW
3360=item Missing braces on \o{}
3361
3362(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3363
a0d0e21e
LW
3364=item Missing comma after first argument to %s function
3365
3366(F) While certain functions allow you to specify a filehandle or an