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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
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75=item alpha->numify() is lossy
76
77(W numeric) An alpha version can not be numified without losing
78information.
79
6df41af2 80=item Ambiguous call resolved as CORE::%s(), qualify as such or use &
43192e07 81
75b44862 82(W ambiguous) A subroutine you have declared has the same name as a Perl
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83keyword, and you have used the name without qualification for calling
84one or the other. Perl decided to call the builtin because the
85subroutine is not imported.
43192e07 86
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87To force interpretation as a subroutine call, either put an ampersand
88before the subroutine name, or qualify the name with its package.
89Alternatively, you can import the subroutine (or pretend that it's
90imported with the C<use subs> pragma).
43192e07 91
6df41af2 92To silently interpret it as the Perl operator, use the C<CORE::> prefix
496a33f5 93on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
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94to be an object method (see L<perlsub/"Subroutine Attributes"> or
95L<attributes>).
43192e07 96
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97=item Ambiguous range in transliteration operator
98
99(F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
100all. To include a C<-> character in a transliteration, put it either
101first or last. (In the past, C<tr/a-z-0//> was synonymous with
102C<tr/a-y//>, which was probably not what you would have expected.)
103
6df41af2 104=item Ambiguous use of %s resolved as %s
43192e07 105
7c7af292 106(S ambiguous) You said something that may not be interpreted the way
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107you thought. Normally it's pretty easy to disambiguate it by supplying
108a missing quote, operator, parenthesis pair or declaration.
a0d0e21e 109
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110=item Ambiguous use of -%s resolved as -&%s()
111
112(S ambiguous) You wrote something like C<-foo>, which might be the
113string C<"-foo">, or a call to the function C<foo>, negated. If you meant
114the string, just write C<"-foo">. If you meant the function call,
115write C<-foo()>.
116
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117=item Ambiguous use of %c resolved as operator %c
118
7c7af292 119(S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
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120bitwise and, and multiplication) I<and> initial special characters
121(denoting hashes, subroutines and typeglobs), and you said something
122like C<*foo * foo> that might be interpreted as either of them. We
123assumed you meant the infix operator, but please try to make it more
124clear -- in the example given, you might write C<*foo * foo()> if you
125really meant to multiply a glob by the result of calling a function.
d8225693 126
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127=item Ambiguous use of %c{%s} resolved to %c%s
128
129(W ambiguous) You wrote something like C<@{foo}>, which might be
130asking for the variable C<@foo>, or it might be calling a function
131named foo, and dereferencing it as an array reference. If you wanted
1cecf2c0 132the variable, you can just write C<@foo>. If you wanted to call the
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133function, write C<@{foo()}> ... or you could just not have a variable
134and a function with the same name, and save yourself a lot of trouble.
135
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136=item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
137
138=item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
4da60377 139
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140(W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
141the name of a Perl keyword), which might be looking for element number
1422 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
143might have meant to pass an anonymous arrayref to the function named
144foo, and then do a scalar deref on the value it returns. If you meant
145that, write C<${foo([2])}>.
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146
147In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
148to disambiguate between array subscripts and character classes.
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149C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
150by the character class C<[2345]>. If an array subscript is what you
151want, you can avoid the warning by changing C</${length[2345]}/> to the
152unsightly C</${\$length[2345]}/>, by renaming your array to something
153that does not coincide with a built-in keyword, or by simply turning
154off warnings with C<no warnings 'ambiguous';>.
4da60377 155
6df41af2 156=item '|' and '<' may not both be specified on command line
a0d0e21e 157
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158(F) An error peculiar to VMS. Perl does its own command line
159redirection, and found that STDIN was a pipe, and that you also tried to
160redirect STDIN using '<'. Only one STDIN stream to a customer, please.
c9f97d15 161
6df41af2 162=item '|' and '>' may not both be specified on command line
1028017a 163
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164(F) An error peculiar to VMS. Perl does its own command line
165redirection, and thinks you tried to redirect stdout both to a file and
166into a pipe to another command. You need to choose one or the other,
167though nothing's stopping you from piping into a program or Perl script
168which 'splits' output into two streams, such as
1028017a 169
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170 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
171 while (<STDIN>) {
172 print;
173 print OUT;
174 }
175 close OUT;
c9f97d15 176
6df41af2 177=item Applying %s to %s will act on scalar(%s)
eb6e2d6f 178
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179(W misc) The pattern match (C<//>), substitution (C<s///>), and
180transliteration (C<tr///>) operators work on scalar values. If you apply
be771a83 181one of them to an array or a hash, it will convert the array or hash to
ac036724 182a scalar value (the length of an array, or the population info of a
183hash) and then work on that scalar value. This is probably not what
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184you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
185alternatives.
eb6e2d6f 186
6df41af2 187=item Arg too short for msgsnd
76cd736e 188
6df41af2 189(F) msgsnd() requires a string at least as long as sizeof(long).
76cd736e 190
f86702cc 191=item Argument "%s" isn't numeric%s
a0d0e21e 192
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193(W numeric) The indicated string was fed as an argument to an operator
194that expected a numeric value instead. If you're fortunate the message
195will identify which operator was so unfortunate.
a0d0e21e 196
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197Note that for the C<Inf> and C<NaN> (infinity and not-a-number) the
198definition of "numeric" is somewhat unusual: the strings themselves
199(like "Inf") are considered numeric, and anything following them is
200considered non-numeric.
201
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202=item Argument list not closed for PerlIO layer "%s"
203
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204(W layer) When pushing a layer with arguments onto the Perl I/O
205system you forgot the ) that closes the argument list. (Layers
206take care of transforming data between external and internal
207representations.) Perl stopped parsing the layer list at this
208point and did not attempt to push this layer. If your program
209didn't explicitly request the failing operation, it may be the
210result of the value of the environment variable PERLIO.
b4581f09 211
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212=item Argument "%s" treated as 0 in increment (++)
213
214(W numeric) The indicated string was fed as an argument to the C<++>
215operator which expects either a number or a string matching
216C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
217Auto-decrement> for details.
218
637494ac 219=item Array passed to stat will be coerced to a scalar%s
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220
221(W syntax) You called stat() on an array, but the array will be
222coerced to a scalar - the number of elements in the array.
223
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224=item A signature parameter must start with '$', '@' or '%'
225
226(F) Each subroutine signature parameter declaration must start with a valid
227sigil; for example:
228
229 sub foo ($a, $, $b = 1, @c) {}
230
231=item A slurpy parameter may not have a default value
232
233(F) Only scalar subroutine signature parameters may have a default value;
234for example:
235
236 sub foo ($a = 1) {} # legal
237 sub foo (@a = (1)) {} # invalid
238 sub foo (%a = (a => b)) {} # invalid
239
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240=item assertion botched: %s
241
21b5e840 242(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 243
0eacef8e 244=item Assertion %s failed: file "%s", line %d
a0d0e21e 245
21b5e840 246(X) A general assertion failed. The file in question must be examined.
a0d0e21e 247
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248=item Assigned value is not a reference
249
250(F) You tried to assign something that was not a reference to an lvalue
251reference (e.g., C<\$x = $y>). If you meant to make $x an alias to $y, use
252C<\$x = \$y>.
253
254=item Assigned value is not %s reference
255
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256(F) You tried to assign a reference to a reference constructor, but the
257two references were not of the same type. You cannot alias a scalar to
258an array, or an array to a hash; the two types must match.
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259
260 \$x = \@y; # error
261 \@x = \%y; # error
262 $y = [];
263 \$x = $y; # error; did you mean \$y?
264
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265=item Assigning non-zero to $[ is no longer possible
266
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267(F) When the "array_base" feature is disabled
268(e.g., and under C<use v5.16;>, and as of Perl 5.30)
7d345e3d 269the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 270
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271=item Assignment to both a list and a scalar
272
273(F) If you assign to a conditional operator, the 2nd and 3rd arguments
274must either both be scalars or both be lists. Otherwise Perl won't
275know which context to supply to the right side.
276
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277=item Assuming NOT a POSIX class since %s in regex; marked by S<<-- HERE> in m/%s/
278
279(W regexp) You had something like these:
280
281 [[:alnum]]
282 [[:digit:xyz]
283
284They look like they might have been meant to be the POSIX classes
285C<[:alnum:]> or C<[:digit:]>. If so, they should be written:
286
287 [[:alnum:]]
288 [[:digit:]xyz]
289
290Since these aren't legal POSIX class specifications, but are legal
291bracketed character classes, Perl treats them as the latter. In the
292first example, it matches the characters C<":">, C<"[">, C<"a">, C<"l">,
293C<"m">, C<"n">, and C<"u">.
294
295If these weren't meant to be POSIX classes, this warning message is
296spurious, and can be suppressed by reordering things, such as
297
298 [[al:num]]
299
300or
301
302 [[:munla]]
303
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304=item <> at require-statement should be quotes
305
306(F) You wrote C<< require <file> >> when you should have written
307C<require 'file'>.
308
2393f1b9 309=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 310
49293501 311(F) The failing code has attempted to get or set a key which is not in
2393f1b9 312the current set of allowed keys of a restricted hash.
49293501 313
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FC
314=item Attempt to bless into a freed package
315
316(F) You wrote C<bless $foo> with one argument after somehow causing
317the current package to be freed. Perl cannot figure out what to
0c5a5b27 318do, so it throws up its hands in despair.
dcdfe746 319
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320=item Attempt to bless into a reference
321
322(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 323the name of the package to bless the resulting object into. You've
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324supplied instead a reference to something: perhaps you wrote
325
326 bless $self, $proto;
327
328when you intended
329
330 bless $self, ref($proto) || $proto;
331
332If you actually want to bless into the stringified version
333of the reference supplied, you need to stringify it yourself, for
334example by:
335
336 bless $self, "$proto";
337
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FC
338=item Attempt to clear deleted array
339
340(S debugging) An array was assigned to when it was being freed.
341Freed values are not supposed to be visible to Perl code. This
342can also happen if XS code calls C<av_clear> from a custom magic
343callback on the array.
344
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345=item Attempt to delete disallowed key '%s' from a restricted hash
346
347(F) The failing code attempted to delete from a restricted hash a key
348which is not in its key set.
349
350=item Attempt to delete readonly key '%s' from a restricted hash
351
352(F) The failing code attempted to delete a key whose value has been
353declared readonly from a restricted hash.
354
de42a5a9 355=item Attempt to free non-arena SV: 0x%x
a0d0e21e 356
f84fe999 357(S internal) All SV objects are supposed to be allocated from arenas
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358that will be garbage collected on exit. An SV was discovered to be
359outside any of those arenas.
a0d0e21e 360
12578ffb 361=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 362
f84fe999 363(S internal) Perl maintains a reference-counted internal table of
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364strings to optimize the storage and access of hash keys and other
365strings. This indicates someone tried to decrement the reference count
366of a string that can no longer be found in the table.
bbce6d69 367
7d5b40b4 368=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 369
f84fe999 370(S debugging) Mortalized values are supposed to be freed by the
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371free_tmps() routine. This indicates that something else is freeing the
372SV before the free_tmps() routine gets a chance, which means that the
373free_tmps() routine will be freeing an unreferenced scalar when it does
374try to free it.
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375
376=item Attempt to free unreferenced glob pointers
377
f84fe999 378(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 379
7d5b40b4 380=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 381
8f7e4d2c 382(S internal) Perl went to decrement the reference count of a scalar to
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383see if it would go to 0, and discovered that it had already gone to 0
384earlier, and should have been freed, and in fact, probably was freed.
385This could indicate that SvREFCNT_dec() was called too many times, or
386that SvREFCNT_inc() was called too few times, or that the SV was
387mortalized when it shouldn't have been, or that memory has been
388corrupted.
a0d0e21e 389
84902520
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390=item Attempt to pack pointer to temporary value
391
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392(W pack) You tried to pass a temporary value (like the result of a
393function, or a computed expression) to the "p" pack() template. This
394means the result contains a pointer to a location that could become
395invalid anytime, even before the end of the current statement. Use
396literals or global values as arguments to the "p" pack() template to
397avoid this warning.
84902520 398
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399=item Attempt to reload %s aborted.
400
401(F) You tried to load a file with C<use> or C<require> that failed to
402compile once already. Perl will not try to compile this file again
403unless you delete its entry from %INC. See L<perlfunc/require> and
404L<perlvar/%INC>.
405
1b20cd17
NC
406=item Attempt to set length of freed array
407
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FC
408(W misc) You tried to set the length of an array which has
409been freed. You can do this by storing a reference to the
410scalar representing the last index of an array and later
411assigning through that reference. For example
1b20cd17
NC
412
413 $r = do {my @a; \$#a};
414 $$r = 503
415
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416=item Attempt to use reference as lvalue in substr
417
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418(W substr) You supplied a reference as the first argument to substr()
419used as an lvalue, which is pretty strange. Perhaps you forgot to
420dereference it first. See L<perlfunc/substr>.
b7a902f4 421
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FC
422=item Attribute prototype(%s) discards earlier prototype attribute in same sub
423
424(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
425example. Since each sub can only have one prototype, the earlier
426declaration(s) are discarded while the last one is applied.
427
ccce04a4
FC
428=item av_reify called on tied array
429
430(S debugging) This indicates that something went wrong and Perl got I<very>
431confused about C<@_> or C<@DB::args> being tied.
432
de42a5a9 433=item Bad arg length for %s, is %u, should be %d
a0d0e21e 434
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435(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
436or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 437S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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438S<sizeof(struct shmid_ds *)>.
439
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440=item Bad evalled substitution pattern
441
496a33f5 442(F) You've used the C</e> switch to evaluate the replacement for a
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443substitution, but perl found a syntax error in the code to evaluate,
444most likely an unexpected right brace '}'.
445
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446=item Bad filehandle: %s
447
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448(F) A symbol was passed to something wanting a filehandle, but the
449symbol has no filehandle associated with it. Perhaps you didn't do an
450open(), or did it in another package.
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451
452=item Bad free() ignored
453
be771a83 454(S malloc) An internal routine called free() on something that had never
fa816bf3 455been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 456setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 457
9ea8bc6d 458This message can be seen quite often with DB_File on systems with "hard"
6903afa2 459dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 460which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 461
aa689395
PP
462=item Bad hash
463
464(P) One of the internal hash routines was passed a null HV pointer.
465
6df41af2
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466=item Badly placed ()'s
467
468(A) You've accidentally run your script through B<csh> instead
469of Perl. Check the #! line, or manually feed your script into
470Perl yourself.
471
a7cb8dae 472=item Bad name after %s
a0d0e21e 473
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474(F) You started to name a symbol by using a package prefix, and then
475didn't finish the symbol. In particular, you can't interpolate outside
476of quotes, so
a0d0e21e
LW
477
478 $var = 'myvar';
479 $sym = mypack::$var;
480
481is not the same as
482
483 $var = 'myvar';
484 $sym = "mypack::$var";
485
88e1f1a2
JV
486=item Bad plugin affecting keyword '%s'
487
488(F) An extension using the keyword plugin mechanism violated the
489plugin API.
490
4ad56ec9
IZ
491=item Bad realloc() ignored
492
6903afa2
FC
493(S malloc) An internal routine called realloc() on something that
494had never been malloc()ed in the first place. Mandatory, but can
495be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 496
a0d0e21e
LW
497=item Bad symbol for array
498
499(P) An internal request asked to add an array entry to something that
500wasn't a symbol table entry.
501
4df3f177
SP
502=item Bad symbol for dirhandle
503
504(P) An internal request asked to add a dirhandle entry to something
505that wasn't a symbol table entry.
506
a0d0e21e
LW
507=item Bad symbol for filehandle
508
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509(P) An internal request asked to add a filehandle entry to something
510that wasn't a symbol table entry.
a0d0e21e
LW
511
512=item Bad symbol for hash
513
514(P) An internal request asked to add a hash entry to something that
515wasn't a symbol table entry.
516
e6d55c99
FC
517=item Bad symbol for scalar
518
519(P) An internal request asked to add a scalar entry to something that
520wasn't a symbol table entry.
521
34d09196
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522=item Bareword found in conditional
523
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524(W bareword) The compiler found a bareword where it expected a
525conditional, which often indicates that an || or && was parsed as part
526of the last argument of the previous construct, for example:
34d09196
GS
527
528 open FOO || die;
529
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530It may also indicate a misspelled constant that has been interpreted as
531a bareword:
34d09196
GS
532
533 use constant TYPO => 1;
534 if (TYOP) { print "foo" }
535
536The C<strict> pragma is useful in avoiding such errors.
537
a52f2cce
NC
538=item Bareword in require contains "%s"
539
a52f2cce
NC
540=item Bareword in require maps to disallowed filename "%s"
541
09eb1f39 542=item Bareword in require maps to empty filename
5bad2b39 543
a52f2cce 544(F) The bareword form of require has been invoked with a filename which could
d4e5761f 545not have been generated by a valid bareword permitted by the parser. You
a52f2cce
NC
546shouldn't be able to get this error from Perl code, but XS code may throw it
547if it passes an invalid module name to C<Perl_load_module>.
548
5bad2b39
DM
549=item Bareword in require must not start with a double-colon: "%s"
550
551(F) In C<require Bare::Word>, the bareword is not allowed to start with a
d4e5761f 552double-colon. Write C<require ::Foo::Bar> as C<require Foo::Bar> instead.
5bad2b39 553
6df41af2
GS
554=item Bareword "%s" not allowed while "strict subs" in use
555
556(F) With "strict subs" in use, a bareword is only allowed as a
be771a83
GS
557subroutine identifier, in curly brackets or to the left of the "=>"
558symbol. Perhaps you need to predeclare a subroutine?
6df41af2
GS
559
560=item Bareword "%s" refers to nonexistent package
561
be771a83
GS
562(W bareword) You used a qualified bareword of the form C<Foo::>, but the
563compiler saw no other uses of that namespace before that point. Perhaps
564you need to predeclare a package?
6df41af2 565
a0d0e21e
LW
566=item BEGIN failed--compilation aborted
567
be771a83
GS
568(F) An untrapped exception was raised while executing a BEGIN
569subroutine. Compilation stops immediately and the interpreter is
570exited.
a0d0e21e 571
68dc0745
PP
572=item BEGIN not safe after errors--compilation aborted
573
574(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
be771a83
GS
575implies a C<BEGIN {}>) after one or more compilation errors had already
576occurred. Since the intended environment for the C<BEGIN {}> could not
577be guaranteed (due to the errors), and since subsequent code likely
578depends on its correct operation, Perl just gave up.
68dc0745 579
c782d7ee 580=item \%d better written as $%d
6df41af2 581
be771a83
GS
582(W syntax) Outside of patterns, backreferences live on as variables.
583The use of backslashes is grandfathered on the right-hand side of a
584substitution, but stylistically it's better to use the variable form
585because other Perl programmers will expect it, and it works better if
586there are more than 9 backreferences.
6df41af2 587
252aa082
JH
588=item Binary number > 0b11111111111111111111111111111111 non-portable
589
e476b1b5 590(W portable) The binary number you specified is larger than 2**32-1
9e24b6e2
JH
591(4294967295) and therefore non-portable between systems. See
592L<perlport> for more on portability concerns.
252aa082 593
69282e91 594=item bind() on closed socket %s
a0d0e21e 595
be771a83
GS
596(W closed) You tried to do a bind on a closed socket. Did you forget to
597check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 598
c289d2f7
JH
599=item binmode() on closed filehandle %s
600
601(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 602Check your control flow and number of arguments.
c289d2f7 603
c5a0f51a
JH
604=item Bit vector size > 32 non-portable
605
e476b1b5 606(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 607
043c750c 608=item Bizarre copy of %s
4633a7c4 609
be771a83 610(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 611copiable.
4633a7c4 612
5a25739d
FC
613=item Bizarre SvTYPE [%d]
614
434f489b 615(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
616encountered an invalid data type.
617
b927b7e9 618=item Both or neither range ends should be Unicode in regex; marked by
6e8a73f2 619S<<-- HERE> in m/%s/
b927b7e9
KW
620
621(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
622
623In a bracketed character class in a regular expression pattern, you
624had a range which has exactly one end of it specified using C<\N{}>, and
625the other end is specified using a non-portable mechanism. Perl treats
626the range as a Unicode range, that is, all the characters in it are
627considered to be the Unicode characters, and which may be different code
628points on some platforms Perl runs on. For example, C<[\N{U+06}-\x08]>
629is treated as if you had instead said C<[\N{U+06}-\N{U+08}]>, that is it
630matches the characters whose code points in Unicode are 6, 7, and 8.
631But that C<\x08> might indicate that you meant something different, so
632the warning gets raised.
633
f675dbe5
CB
634=item Buffer overflow in prime_env_iter: %s
635
be771a83
GS
636(W internal) A warning peculiar to VMS. While Perl was preparing to
637iterate over %ENV, it encountered a logical name or symbol definition
638which was too long, so it was truncated to the string shown.
f675dbe5 639
a0d0e21e
LW
640=item Callback called exit
641
4929bf7b 642(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
643exited by calling exit.
644
6df41af2 645=item %s() called too early to check prototype
f675dbe5 646
be771a83
GS
647(W prototype) You've called a function that has a prototype before the
648parser saw a definition or declaration for it, and Perl could not check
649that the call conforms to the prototype. You need to either add an
650early prototype declaration for the subroutine in question, or move the
651subroutine definition ahead of the call to get proper prototype
652checking. Alternatively, if you are certain that you're calling the
653function correctly, you may put an ampersand before the name to avoid
654the warning. See L<perlsub>.
f675dbe5 655
0c7df902
JH
656=item Cannot chr %f
657
658(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
659
1b4d0d79
TC
660=item Cannot complete in-place edit of %s: %s
661
662(F) Your perl script appears to have changed directory while
663performing an in-place edit of a file specified by a relative path,
664and your system doesn't include the directory relative POSIX functions
665needed to handle that.
666
5dee29d4 667=item Cannot compress %f in pack
0c7df902 668
5dee29d4
JH
669(F) You tried compressing an infinity or not-a-number as an unsigned
670integer with BER, which makes no sense.
0c7df902 671
49704364 672=item Cannot compress integer in pack
0258719b 673
717feafc
JH
674(F) An argument to pack("w",...) was too large to compress.
675The BER compressed integer format can only be used with positive
676integers, and you attempted to compress a very large number (> 1e308).
677See L<perlfunc/pack>.
0258719b 678
49704364 679=item Cannot compress negative numbers in pack
0258719b
NC
680
681(F) An argument to pack("w",...) was negative. The BER compressed integer
682format can only be used with positive integers. See L<perlfunc/pack>.
683
5c1f4d79
NC
684=item Cannot convert a reference to %s to typeglob
685
6903afa2
FC
686(F) You manipulated Perl's symbol table directly, stored a reference
687in it, then tried to access that symbol via conventional Perl syntax.
688The access triggers Perl to autovivify that typeglob, but it there is
689no legal conversion from that type of reference to a typeglob.
5c1f4d79 690
4040665a 691=item Cannot copy to %s
ba2fdce6
NC
692
693(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 694be directly assigned to.
ba2fdce6 695
b5d97229
RGS
696=item Cannot find encoding "%s"
697
698(S io) You tried to apply an encoding that did not exist to a filehandle,
699either with open() or binmode().
700
714f94d1
FC
701=item Cannot open %s as a dirhandle: it is already open as a filehandle
702
703(F) You tried to use opendir() to associate a dirhandle to a symbol (glob
704or scalar) that already holds a filehandle. Since this idiom might render
705your code confusing, it was deprecated in Perl 5.10. As of Perl 5.28, it
706is a fatal error.
707
708=item Cannot open %s as a filehandle: it is already open as a dirhandle
709
710(F) You tried to use open() to associate a filehandle to a symbol (glob
711or scalar) that already holds a dirhandle. Since this idiom might render
712your code confusing, it was deprecated in Perl 5.10. As of Perl 5.28, it
713is a fatal error.
714
0c7df902
JH
715=item Cannot pack %f with '%c'
716
5dee29d4 717(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
718which makes no sense.
719
720=item Cannot printf %f with '%c'
721
722(F) You tried printing an infinity or not-a-number as a character (%c),
723which makes no sense. Maybe you meant '%s', or just stringifying it?
724
7355df7e
FC
725=item Cannot set tied @DB::args
726
727(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
728is not supported. (Before this error was added, it used to crash.)
729
ce65bc73
FC
730=item Cannot tie unreifiable array
731
732(P) You somehow managed to call C<tie> on an array that does not
733keep a reference count on its arguments and cannot be made to
734do so. Such arrays are not even supposed to be accessible to
735Perl code, but are only used internally.
736
26b0dc0c 737=item Cannot yet reorder sv_vcatpvfn() arguments from va_list
46e58bd2 738
26b0dc0c 739(F) Some XS code tried to use C<sv_vcatpvfn()> or a related function with a
46e58bd2 740format string that specifies explicit indexes for some of the elements, and
d4e5761f
FC
741using a C-style variable-argument list (a C<va_list>). This is not currently
742supported. XS authors wanting to do this must instead construct a C array
743of C<SV*> scalars containing the arguments.
46e58bd2 744
96ebfdd7
RK
745=item Can only compress unsigned integers in pack
746
747(F) An argument to pack("w",...) was not an integer. The BER compressed
748integer format can only be used with positive integers, and you attempted
749to compress something else. See L<perlfunc/pack>.
750
a0d0e21e
LW
751=item Can't bless non-reference value
752
753(F) Only hard references may be blessed. This is how Perl "enforces"
754encapsulation of objects. See L<perlobj>.
755
7896dde7
Z
756=item Can't "break" in a loop topicalizer
757
758(F) You called C<break>, but you're in a C<foreach> block rather than
759a C<given> block. You probably meant to use C<next> or C<last>.
760
761=item Can't "break" outside a given block
762
763(F) You called C<break>, but you're not inside a C<given> block.
764
6df41af2
GS
765=item Can't call method "%s" on an undefined value
766
767(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
768object reference or package name contains an undefined value. Something
769like this will reproduce the error:
6df41af2
GS
770
771 $BADREF = undef;
772 process $BADREF 1,2,3;
773 $BADREF->process(1,2,3);
774
a0d0e21e
LW
775=item Can't call method "%s" on unblessed reference
776
54310121 777(F) A method call must know in what package it's supposed to run. It
be771a83
GS
778ordinarily finds this out from the object reference you supply, but you
779didn't supply an object reference in this case. A reference isn't an
780object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
781
782=item Can't call method "%s" without a package or object reference
783
784(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
785object reference or package name contains an expression that returns a
786defined value which is neither an object reference nor a package name.
72b5445b
GS
787Something like this will reproduce the error:
788
789 $BADREF = 42;
790 process $BADREF 1,2,3;
791 $BADREF->process(1,2,3);
792
dfe378f1
FC
793=item Can't call mro_isa_changed_in() on anonymous symbol table
794
795(P) Perl got confused as to whether a hash was a plain hash or a
796symbol table hash when trying to update @ISA caches.
797
2bf7e7b2
FC
798=item Can't call mro_method_changed_in() on anonymous symbol table
799
800(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
801not attached to the symbol table.
802
a0d0e21e
LW
803=item Can't chdir to %s
804
f703fc96 805(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
806that you can chdir to, possibly because it doesn't exist.
807
0545a864 808=item Can't check filesystem of script "%s" for nosuid
104d25b7 809
be771a83
GS
810(P) For some reason you can't check the filesystem of the script for
811nosuid.
104d25b7 812
22e74366 813=item Can't coerce %s to %s in %s
a0d0e21e
LW
814
815(F) Certain types of SVs, in particular real symbol table entries
55497cff 816(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
817say things like:
818
819 *foo += 1;
820
821You CAN say
822
823 $foo = *foo;
824 $foo += 1;
825
826but then $foo no longer contains a glob.
827
7896dde7 828=item Can't "continue" outside a when block
dc57907a 829
7896dde7
Z
830(F) You called C<continue>, but you're not inside a C<when>
831or C<default> block.
0d863452 832
a0d0e21e
LW
833=item Can't create pipe mailbox
834
be771a83
GS
835(P) An error peculiar to VMS. The process is suffering from exhausted
836quotas or other plumbing problems.
a0d0e21e 837
eb64745e
GS
838=item Can't declare %s in "%s"
839
30c282f6
NC
840(F) Only scalar, array, and hash variables may be declared as "my", "our" or
841"state" variables. They must have ordinary identifiers as names.
a0d0e21e 842
7896dde7
Z
843=item Can't "default" outside a topicalizer
844
845(F) You have used a C<default> block that is neither inside a
846C<foreach> loop nor a C<given> block. (Note that this error is
847issued on exit from the C<default> block, so you won't get the
848error if you use an explicit C<continue>.)
849
1e85b658
DM
850=item Can't determine class of operator %s, assuming BASEOP
851
852(S) This warning indicates something wrong in the internals of perl.
853Perl was trying to find the class (e.g. LISTOP) of a particular OP,
854and was unable to do so. This is likely to be due to a bug in the perl
855internals, or due to a bug in XS code which manipulates perl optrees.
856
a2162cd9
FC
857=item Can't do inplace edit: %s is not a regular file
858
859(S inplace) You tried to use the B<-i> switch on a special file, such as
860a file in /dev, a FIFO or an uneditable directory. The file was ignored.
861
862=item Can't do inplace edit on %s: %s
863
864(S inplace) The creation of the new file failed for the indicated
865reason.
866
a2162cd9
FC
867=item Can't do inplace edit: %s would not be unique
868
869(S inplace) Your filesystem does not support filenames longer than 14
870characters and Perl was unable to create a unique filename during
871inplace editing with the B<-i> switch. The file was ignored.
872
ab0b796c
KW
873=item Can't do %s("%s") on non-UTF-8 locale; resolved to "%s".
874
875(W locale) You are 1) running under "C<use locale>"; 2) the current
876locale is not a UTF-8 one; 3) you tried to do the designated case-change
877operation on the specified Unicode character; and 4) the result of this
878operation would mix Unicode and locale rules, which likely conflict.
879Mixing of different rule types is forbidden, so the operation was not
880done; instead the result is the indicated value, which is the best
881available that uses entirely Unicode rules. That turns out to almost
882always be the original character, unchanged.
883
884It is generally a bad idea to mix non-UTF-8 locales and Unicode, and
885this issue is one of the reasons why. This warning is raised when
886Unicode rules would normally cause the result of this operation to
887contain a character that is in the range specified by the locale,
8880..255, and hence is subject to the locale's rules, not Unicode's.
889
890If you are using locale purely for its characteristics related to things
891like its numeric and time formatting (and not C<LC_CTYPE>), consider
892using a restricted form of the locale pragma (see L<perllocale/The "use
893locale" pragma>) like "S<C<use locale ':not_characters'>>".
894
895Note that failed case-changing operations done as a result of
896case-insensitive C</i> regular expression matching will show up in this
897warning as having the C<fc> operation (as that is what the regular
898expression engine calls behind the scenes.)
899
a0d0e21e
LW
900=item Can't do waitpid with flags
901
be771a83
GS
902(F) This machine doesn't have either waitpid() or wait4(), so only
903waitpid() without flags is emulated.
a0d0e21e 904
a0d0e21e
LW
905=item Can't emulate -%s on #! line
906
be771a83
GS
907(F) The #! line specifies a switch that doesn't make sense at this
908point. For example, it'd be kind of silly to put a B<-x> on the #!
909line.
a0d0e21e 910
1109a392
MHM
911=item Can't %s %s-endian %ss on this platform
912
913(F) Your platform's byte-order is neither big-endian nor little-endian,
914or it has a very strange pointer size. Packing and unpacking big- or
915little-endian floating point values and pointers may not be possible.
916See L<perlfunc/pack>.
917
a0d0e21e
LW
918=item Can't exec "%s": %s
919
d1be9408 920(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
921named program for the indicated reason. Typical reasons include: the
922permissions were wrong on the file, the file wasn't found in
923C<$ENV{PATH}>, the executable in question was compiled for another
924architecture, or the #! line in a script points to an interpreter that
925can't be run for similar reasons. (Or maybe your system doesn't support
926#! at all.)
a0d0e21e
LW
927
928=item Can't exec %s
929
be771a83
GS
930(F) Perl was trying to execute the indicated program for you because
931that's what the #! line said. If that's not what you wanted, you may
932need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
933
934=item Can't execute %s
935
be771a83
GS
936(F) You used the B<-S> switch, but the copies of the script to execute
937found in the PATH did not have correct permissions.
2a92aaa0 938
6df41af2 939=item Can't find an opnumber for "%s"
2a92aaa0 940
be771a83
GS
941(F) A string of a form C<CORE::word> was given to prototype(), but there
942is no builtin with the name C<word>.
6df41af2
GS
943
944=item Can't find label %s
945
be771a83
GS
946(F) You said to goto a label that isn't mentioned anywhere that it's
947possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
948
949=item Can't find %s on PATH
950
be771a83
GS
951(F) You used the B<-S> switch, but the script to execute could not be
952found in the PATH.
a0d0e21e 953
6df41af2 954=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 955
be771a83
GS
956(F) You used the B<-S> switch, but the script to execute could not be
957found in the PATH, or at least not with the correct permissions. The
958script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
959
960=item Can't find string terminator %s anywhere before EOF
961
be771a83
GS
962(F) Perl strings can stretch over multiple lines. This message means
963that the closing delimiter was omitted. Because bracketed quotes count
964nesting levels, the following is missing its final parenthesis:
a0d0e21e 965
fb73857a
PP
966 print q(The character '(' starts a side comment.);
967
97b3d10f 968If you're getting this error from a here-document, you may have
b6b8cb97
FC
969included unseen whitespace before or after your closing tag or there
970may not be a linebreak after it. A good programmer's editor will have
971a way to help you find these characters (or lack of characters). See
972L<perlop> for the full details on here-documents.
a0d0e21e 973
660a4616
ST
974=item Can't find Unicode property definition "%s"
975
29f52644
KW
976=item Can't find Unicode property definition "%s" in regex; marked by <-- HERE in m/%s/
977
978(F) The named property which you specified via C<\p> or C<\P> is not one
979known to Perl. Perhaps you misspelled the name? See
e1b711da 980L<perluniprops/Properties accessible through \p{} and \P{}>
29f52644
KW
981for a complete list of available official
982properties. If it is a
983L<user-defined property|perlunicode/User-Defined Character Properties>
984it must have been defined by the time the regular expression is
985matched.
986
987If you didn't mean to use a Unicode property, escape the C<\p>, either
988by C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 989until C<\E>).
660a4616 990
b3647a36 991=item Can't fork: %s
a0d0e21e 992
be771a83
GS
993(F) A fatal error occurred while trying to fork while opening a
994pipeline.
a0d0e21e 995
b3647a36
SR
996=item Can't fork, trying again in 5 seconds
997
c973c02e 998(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
999after five seconds.
1000
748a9306
LW
1001=item Can't get filespec - stale stat buffer?
1002
be771a83
GS
1003(S) A warning peculiar to VMS. This arises because of the difference
1004between access checks under VMS and under the Unix model Perl assumes.
1005Under VMS, access checks are done by filename, rather than by bits in
1006the stat buffer, so that ACLs and other protections can be taken into
1007account. Unfortunately, Perl assumes that the stat buffer contains all
1008the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 1009the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
1010the device name and FID present in the stat buffer, but this works only
1011if you haven't made a subsequent call to the CRTL stat() routine,
1012because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
1013appears, the name lookup failed, and the access-checking routine gave up
1014and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
1015routine knows about the Perl C<stat> operator and file tests, so you
1016shouldn't ever see this warning in response to a Perl command; it arises
1017only if some internal code takes stat buffers lightly.)
748a9306 1018
a0d0e21e
LW
1019=item Can't get pipe mailbox device name
1020
be771a83
GS
1021(P) An error peculiar to VMS. After creating a mailbox to act as a
1022pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
1023
1024=item Can't get SYSGEN parameter value for MAXBUF
1025
748a9306
LW
1026(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
1027mailbox buffers to be, and didn't get an answer.
a0d0e21e 1028
6d90e983
FC
1029=item Can't "goto" into a binary or list expression
1030
1031(F) A "goto" statement was executed to jump into the middle of a binary
1032or list expression. You can't get there from here. The reason for this
1033restriction is that the interpreter would get confused as to how many
1034arguments there are, resulting in stack corruption or crashes. This
1035error occurs in cases such as these:
1036
1037 goto F;
1038 print do { F: }; # Can't jump into the arguments to print
1039
1040 goto G;
1041 $x + do { G: $y }; # How is + supposed to get its first operand?
1042
a01f4640
FC
1043=item Can't "goto" into a "given" block
1044
1045(F) A "goto" statement was executed to jump into the middle of a C<given>
1046block. You can't get there from here. See L<perlfunc/goto>.
1047
6df41af2 1048=item Can't "goto" into the middle of a foreach loop
a0d0e21e 1049
be771a83
GS
1050(F) A "goto" statement was executed to jump into the middle of a foreach
1051loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
1052
1053=item Can't "goto" out of a pseudo block
1054
be771a83
GS
1055(F) A "goto" statement was executed to jump out of what might look like
1056a block, except that it isn't a proper block. This usually occurs if
1057you tried to jump out of a sort() block or subroutine, which is a no-no.
1058See L<perlfunc/goto>.
a0d0e21e 1059
5a25739d
FC
1060=item Can't goto subroutine from an eval-%s
1061
1062(F) The "goto subroutine" call can't be used to jump out of an eval
1063"string" or block.
1064
9850bf21 1065=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 1066
9850bf21
RH
1067(F) The "goto subroutine" call can't be used to jump out of the
1068comparison sub for a sort(), or from a similar callback (such
1069as the reduce() function in List::Util).
1070
6df41af2
GS
1071=item Can't goto subroutine outside a subroutine
1072
be771a83
GS
1073(F) The deeply magical "goto subroutine" call can only replace one
1074subroutine call for another. It can't manufacture one out of whole
1075cloth. In general you should be calling it out of only an AUTOLOAD
1076routine anyway. See L<perlfunc/goto>.
6df41af2 1077
0b5b802d
GS
1078=item Can't ignore signal CHLD, forcing to default
1079
be771a83
GS
1080(W signal) Perl has detected that it is being run with the SIGCHLD
1081signal (sometimes known as SIGCLD) disabled. Since disabling this
1082signal will interfere with proper determination of exit status of child
1083processes, Perl has reset the signal to its default value. This
1084situation typically indicates that the parent program under which Perl
1085may be running (e.g. cron) is being very careless.
0b5b802d 1086
e2c0f81f
DG
1087=item Can't kill a non-numeric process ID
1088
1089(F) Process identifiers must be (signed) integers. It is a fatal error to
1090attempt to kill() an undefined, empty-string or otherwise non-numeric
1091process identifier.
1092
6df41af2 1093=item Can't "last" outside a loop block
4633a7c4 1094
6df41af2 1095(F) A "last" statement was executed to break out of the current block,
be771a83
GS
1096except that there's this itty bitty problem called there isn't a current
1097block. Note that an "if" or "else" block doesn't count as a "loopish"
1098block, as doesn't a block given to sort(), map() or grep(). You can
1099usually double the curlies to get the same effect though, because the
1100inner curlies will be considered a block that loops once. See
1101L<perlfunc/last>.
4633a7c4 1102
2c7d6b9c
RGS
1103=item Can't linearize anonymous symbol table
1104
1105(F) Perl tried to calculate the method resolution order (MRO) of a
1106package, but failed because the package stash has no name.
1107
b8170e59
JB
1108=item Can't load '%s' for module %s
1109
6903afa2
FC
1110(F) The module you tried to load failed to load a dynamic extension.
1111This may either mean that you upgraded your version of perl to one
1112that is incompatible with your old dynamic extensions (which is known
1113to happen between major versions of perl), or (more likely) that your
1114dynamic extension was built against an older version of the library
1115that is installed on your system. You may need to rebuild your old
1116dynamic extensions.
b8170e59 1117
748a9306
LW
1118=item Can't localize lexical variable %s
1119
2ba9eb46 1120(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
1121lexical variable using "my" or "state". This is not allowed. If you
1122want to localize a package variable of the same name, qualify it with
1123the package name.
748a9306 1124
6df41af2 1125=item Can't localize through a reference
4727527e 1126
6df41af2
GS
1127(F) You said something like C<local $$ref>, which Perl can't currently
1128handle, because when it goes to restore the old value of whatever $ref
be771a83 1129pointed to after the scope of the local() is finished, it can't be sure
64977eb6 1130that $ref will still be a reference.
4727527e 1131
ea071790 1132=item Can't locate %s
ec889f3a 1133
fa816bf3
FC
1134(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
1135Perl looks for the file in all the locations mentioned in @INC, unless
1136the file name included the full path to the file. Perhaps you need
1137to set the PERL5LIB or PERL5OPT environment variable to say where the
1138extra library is, or maybe the script needs to add the library name
be771a83
GS
1139to @INC. Or maybe you just misspelled the name of the file. See
1140L<perlfunc/require> and L<lib>.
a0d0e21e 1141
6df41af2
GS
1142=item Can't locate auto/%s.al in @INC
1143
be771a83
GS
1144(F) A function (or method) was called in a package which allows
1145autoload, but there is no function to autoload. Most probable causes
1146are a misprint in a function/method name or a failure to C<AutoSplit>
1147the file, say, by doing C<make install>.
6df41af2 1148
b8170e59
JB
1149=item Can't locate loadable object for module %s in @INC
1150
1151(F) The module you loaded is trying to load an external library, like
d70d8e57 1152for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1153unable to locate this library. See L<DynaLoader>.
1154
a0d0e21e
LW
1155=item Can't locate object method "%s" via package "%s"
1156
1157(F) You called a method correctly, and it correctly indicated a package
1158functioning as a class, but that package doesn't define that particular
2ba9eb46 1159method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1160
8af56b9d
FC
1161=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1162to load "%s"?)
1163
1164(F) You called a method on a class that did not exist, and the method
1165could not be found in UNIVERSAL. This often means that a method
1166requires a package that has not been loaded.
1167
a0d0e21e
LW
1168=item Can't locate package %s for @%s::ISA
1169
be771a83
GS
1170(W syntax) The @ISA array contained the name of another package that
1171doesn't seem to exist.
a0d0e21e 1172
2f7da168
RK
1173=item Can't locate PerlIO%s
1174
1175(F) You tried to use in open() a PerlIO layer that does not exist,
1176e.g. open(FH, ">:nosuchlayer", "somefile").
1177
f4ad53f4 1178=item Can't make list assignment to %ENV on this system
3e3baf6d 1179
be771a83
GS
1180(F) List assignment to %ENV is not supported on some systems, notably
1181VMS.
3e3baf6d 1182
cd40cd58
NC
1183=item Can't make loaded symbols global on this platform while loading %s
1184
ff9c1ae8 1185(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1186that symbols from the stated file are made available globally within the
1187process, but that functionality is not available on this platform. Whilst
1188the module likely will still work, this may prevent the perl interpreter
1189from loading other XS-based extensions which need to link directly to
1190functions defined in the C or XS code in the stated file.
1191
a0d0e21e
LW
1192=item Can't modify %s in %s
1193
be771a83
GS
1194(F) You aren't allowed to assign to the item indicated, or otherwise try
1195to change it, such as with an auto-increment.
a0d0e21e 1196
54310121 1197=item Can't modify nonexistent substring
a0d0e21e
LW
1198
1199(P) The internal routine that does assignment to a substr() was handed
1200a NULL.
1201
0f948285 1202=item Can't modify non-lvalue subroutine call of &%s
6df41af2 1203
8d9d0498
FC
1204=item Can't modify non-lvalue subroutine call of &%s in %s
1205
6df41af2 1206(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1207such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1208
cf6e1fa1
FC
1209=item Can't modify reference to %s in %s assignment
1210
1211(F) Only a limited number of constructs can be used as the argument to a
1212reference constructor on the left-hand side of an assignment, and what
1213you used was not one of them. See L<perlref/Assigning to References>.
1214
1215=item Can't modify reference to localized parenthesized array in list
1216assignment
1217
1218(F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1219it is not clear exactly what it should do. If you meant to make @array
1220refer to some other array, use C<\@array = \@other_array>. If you want to
1221make the elements of @array aliases of the scalars referenced on the
1222right-hand side, use C<\(@array) = @scalar_refs>.
1223
1224=item Can't modify reference to parenthesized hash in list assignment
1225
1226(F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1227refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1228make the elements of %hash into aliases of the scalars referenced on the
1229right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1230
5f05dabc 1231=item Can't msgrcv to read-only var
a0d0e21e 1232
5f05dabc 1233(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1234buffer.
1235
6df41af2
GS
1236=item Can't "next" outside a loop block
1237
1238(F) A "next" statement was executed to reiterate the current block, but
1239there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1240count as a "loopish" block, as doesn't a block given to sort(), map() or
1241grep(). You can usually double the curlies to get the same effect
1242though, because the inner curlies will be considered a block that loops
1243once. See L<perlfunc/next>.
6df41af2 1244
a0d0e21e
LW
1245=item Can't open %s: %s
1246
c47ff5f1 1247(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1248filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1249switches, or explicitly, failed for the indicated reason. Usually
1250this is because you don't have read permission for a file which
1251you named on the command line.
1252
1253(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1254your operating system's equivalent) could not be opened.
a0d0e21e 1255
9a869a14
RGS
1256=item Can't open a reference
1257
1258(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1259using the 3-arg open() syntax:
9a869a14
RGS
1260
1261 open FH, '>', $ref;
1262
1263but your version of perl is compiled without perlio, and this form of
1264open is not supported.
1265
a0d0e21e
LW
1266=item Can't open bidirectional pipe
1267
be771a83
GS
1268(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1269You can try any of several modules in the Perl library to do this, such
1270as IPC::Open2. Alternately, direct the pipe's output to a file using
1271">", and then read it in under a different file handle.
a0d0e21e 1272
748a9306
LW
1273=item Can't open error file %s as stderr
1274
be771a83
GS
1275(F) An error peculiar to VMS. Perl does its own command line
1276redirection, and couldn't open the file specified after '2>' or '2>>' on
1277the command line for writing.
748a9306
LW
1278
1279=item Can't open input file %s as stdin
1280
be771a83
GS
1281(F) An error peculiar to VMS. Perl does its own command line
1282redirection, and couldn't open the file specified after '<' on the
1283command line for reading.
748a9306
LW
1284
1285=item Can't open output file %s as stdout
1286
be771a83
GS
1287(F) An error peculiar to VMS. Perl does its own command line
1288redirection, and couldn't open the file specified after '>' or '>>' on
1289the command line for writing.
748a9306
LW
1290
1291=item Can't open output pipe (name: %s)
1292
be771a83
GS
1293(P) An error peculiar to VMS. Perl does its own command line
1294redirection, and couldn't open the pipe into which to send data destined
1295for stdout.
748a9306 1296
3b1cf97d 1297=item Can't open perl script "%s": %s
a0d0e21e
LW
1298
1299(F) The script you specified can't be opened for the indicated reason.
1300
fa3aa65a
JC
1301If you're debugging a script that uses #!, and normally relies on the
1302shell's $PATH search, the -S option causes perl to do that search, so
1303you don't have to type the path or C<`which $scriptname`>.
1304
6df41af2
GS
1305=item Can't read CRTL environ
1306
1307(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1308from the CRTL's internal environment array and discovered the array was
1309missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1310or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1311searched.
6df41af2 1312
f3106bc8
LM
1313=item Can't redeclare "%s" in "%s"
1314
1315(F) A "my", "our" or "state" declaration was found within another declaration,
1316such as C<my ($x, my($y), $z)> or C<our (my $x)>.
1317
6df41af2
GS
1318=item Can't "redo" outside a loop block
1319
1320(F) A "redo" statement was executed to restart the current block, but
1321there isn't a current block. Note that an "if" or "else" block doesn't
1322count as a "loopish" block, as doesn't a block given to sort(), map()
1323or grep(). You can usually double the curlies to get the same effect
1324though, because the inner curlies will be considered a block that
1325loops once. See L<perlfunc/redo>.
1326
64977eb6 1327=item Can't remove %s: %s, skipping file
10f9c03d 1328
be771a83
GS
1329(S inplace) You requested an inplace edit without creating a backup
1330file. Perl was unable to remove the original file to replace it with
1331the modified file. The file was left unmodified.
10f9c03d 1332
e0d4aead
TC
1333=item Can't rename in-place work file '%s' to '%s': %s
1334
1335(F) When closed implicitly, the temporary file for in-place editing
1336couldn't be renamed to the original filename.
1337
ecc6274e
FC
1338=item Can't rename %s to %s: %s, skipping file
1339
1340(F) The rename done by the B<-i> switch failed for some reason,
1341probably because you don't have write permission to the directory.
1342
748a9306
LW
1343=item Can't reopen input pipe (name: %s) in binary mode
1344
be771a83
GS
1345(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1346to reopen it to accept binary data. Alas, it failed.
748a9306 1347
9415f659
KW
1348=item Can't represent character for Ox%X on this platform
1349
1350(F) There is a hard limit to how big a character code point can be due
1351to the fundamental properties of UTF-8, especially on EBCDIC
1352platforms. The given code point exceeds that. The only work-around is
1353to not use such a large code point.
1354
4f12ec0e
FC
1355=item Can't reset %ENV on this system
1356
1357(F) You called C<reset('E')> or similar, which tried to reset
1358all variables in the current package beginning with "E". In
1359the main package, that includes %ENV. Resetting %ENV is not
1360supported on some systems, notably VMS.
1361
fe13d51d 1362=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1363
1fa582fa
FC
1364(F)(P) Error resolving overloading specified by a method name (as
1365opposed to a subroutine reference): no such method callable via the
1366package. If the method name is C<???>, this is an internal error.
6df41af2 1367
cd06dffe
GS
1368=item Can't return %s from lvalue subroutine
1369
be771a83
GS
1370(F) Perl detected an attempt to return illegal lvalues (such as
1371temporary or readonly values) from a subroutine used as an lvalue. This
1372is not allowed.
cd06dffe 1373
96ebfdd7
RK
1374=item Can't return outside a subroutine
1375
1376(F) The return statement was executed in mainline code, that is, where
1377there was no subroutine call to return out of. See L<perlsub>.
1378
78f9721b
SM
1379=item Can't return %s to lvalue scalar context
1380
6903afa2
FC
1381(F) You tried to return a complete array or hash from an lvalue
1382subroutine, but you called the subroutine in a way that made Perl
1383think you meant to return only one value. You probably meant to
1384write parentheses around the call to the subroutine, which tell
1385Perl that the call should be in list context.
78f9721b 1386
a0d0e21e
LW
1387=item Can't stat script "%s"
1388
be771a83
GS
1389(P) For some reason you can't fstat() the script even though you have it
1390open already. Bizarre.
a0d0e21e 1391
a0d0e21e
LW
1392=item Can't take log of %g
1393
fb73857a 1394(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1395negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1396standard with Perl, though, if you really want to do that for the
1397negative numbers.
a0d0e21e
LW
1398
1399=item Can't take sqrt of %g
1400
1401(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1402negative number. There's a Math::Complex package that comes standard
1403with Perl, though, if you really want to do that.
a0d0e21e
LW
1404
1405=item Can't undef active subroutine
1406
1407(F) You can't undefine a routine that's currently running. You can,
1408however, redefine it while it's running, and you can even undef the
1409redefined subroutine while the old routine is running. Go figure.
1410
ecc6274e
FC
1411=item Can't unweaken a nonreference
1412
1413(F) You attempted to unweaken something that was not a reference. Only
1414references can be unweakened.
1415
c81225bc 1416=item Can't upgrade %s (%d) to %d
a0d0e21e 1417
be771a83
GS
1418(P) The internal sv_upgrade routine adds "members" to an SV, making it
1419into a more specialized kind of SV. The top several SV types are so
1420specialized, however, that they cannot be interconverted. This message
1421indicates that such a conversion was attempted.
a0d0e21e 1422
6651ba0b
FC
1423=item Can't use '%c' after -mname
1424
1425(F) You tried to call perl with the B<-m> switch, but you put something
1426other than "=" after the module name.
1427
1f1ec7b5
KW
1428=item Can't use a hash as a reference
1429
1430(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1431C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1432<= 5.22.0 used to allow this syntax, but shouldn't
1433have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1434
1435=item Can't use an array as a reference
1436
1437(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1438C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1439used to allow this syntax, but shouldn't have. This
1440was deprecated in perl 5.6.1.
1f1ec7b5 1441
1db89ea5
BS
1442=item Can't use anonymous symbol table for method lookup
1443
e27ad1f2 1444(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1445table that doesn't have a name. Symbol tables can become anonymous
1446for example by undefining stashes: C<undef %Some::Package::>.
1447
96ebfdd7
RK
1448=item Can't use an undefined value as %s reference
1449
1450(F) A value used as either a hard reference or a symbolic reference must
1451be a defined value. This helps to delurk some insidious errors.
1452
6df41af2
GS
1453=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1454
be771a83
GS
1455(F) Only hard references are allowed by "strict refs". Symbolic
1456references are disallowed. See L<perlref>.
6df41af2 1457
90b75b61 1458=item Can't use %! because Errno.pm is not available
1d2dff63 1459
20561843 1460(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1461Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1462provide symbolic names for C<$!> errno values.
1463
1109a392
MHM
1464=item Can't use both '<' and '>' after type '%c' in %s
1465
1466(F) A type cannot be forced to have both big-endian and little-endian
1467byte-order at the same time, so this combination of modifiers is not
1468allowed. See L<perlfunc/pack>.
1469
e35475de
KW
1470=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1471
1472(F) defined() is not useful on arrays because it
1473checks for an undefined I<scalar> value. If you want to see if the
1474array is empty, just use C<if (@array) { # not empty }> for example.
1475
1476=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1477
1478(F) C<defined()> is not usually right on hashes.
1479
1480Although C<defined %hash> is false on a plain not-yet-used hash, it
1481becomes true in several non-obvious circumstances, including iterators,
1482weak references, stash names, even remaining true after C<undef %hash>.
1483These things make C<defined %hash> fairly useless in practice, so it now
1484generates a fatal error.
1485
1486If a check for non-empty is what you wanted then just put it in boolean
1487context (see L<perldata/Scalar values>):
1488
1489 if (%hash) {
1490 # not empty
1491 }
1492
1493If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1494variable exists then that's never really been reliable, and isn't
1495a good way to enquire about the features of a package, or whether
1496it's loaded, etc.
1497
6df41af2
GS
1498=item Can't use %s for loop variable
1499
c1f06047 1500(P) The parser got confused when trying to parse a C<foreach> loop.
6df41af2 1501
f27832e7 1502=item Can't use global %s in %s
6df41af2 1503
be771a83
GS
1504(F) You tried to declare a magical variable as a lexical variable. This
1505is not allowed, because the magic can be tied to only one location
1506(namely the global variable) and it would be incredibly confusing to
1507have variables in your program that looked like magical variables but
6df41af2
GS
1508weren't.
1509
6d3b25aa
RGS
1510=item Can't use '%c' in a group with different byte-order in %s
1511
1512(F) You attempted to force a different byte-order on a type
1513that is already inside a group with a byte-order modifier.
1514For example you cannot force little-endianness on a type that
1515is inside a big-endian group.
1516
c07a80fd
PP
1517=item Can't use "my %s" in sort comparison
1518
1519(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1520You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1521and the variable had earlier been declared as a lexical variable.
1522Either qualify the sort variable with the package name, or rename the
1523lexical variable.
1524
a0d0e21e
LW
1525=item Can't use %s ref as %s ref
1526
1527(F) You've mixed up your reference types. You have to dereference a
1528reference of the type needed. You can use the ref() function to
1529test the type of the reference, if need be.
1530
748a9306 1531=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1532
5e634d20
FC
1533=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1534
b41bf23f
FC
1535(F) You've told Perl to dereference a string, something which
1536C<use strict> blocks to prevent it happening accidentally. See
1537L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1538in a double-quoted string immediately before interpolating a variable,
1539for example in C<"user @$twitter_id">, which says to treat the contents
1540of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1541symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1542
748a9306
LW
1543=item Can't use subscript on %s
1544
1545(F) The compiler tried to interpret a bracketed expression as a
1546subscript. But to the left of the brackets was an expression that
209e7cf1 1547didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1548
6df41af2
GS
1549=item Can't use \%c to mean $%c in expression
1550
75b44862
GS
1551(W syntax) In an ordinary expression, backslash is a unary operator that
1552creates a reference to its argument. The use of backslash to indicate a
1553backreference to a matched substring is valid only as part of a regular
be771a83
GS
1554expression pattern. Trying to do this in ordinary Perl code produces a
1555value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1556instead.
6df41af2 1557
810b8aa5
GS
1558=item Can't weaken a nonreference
1559
1560(F) You attempted to weaken something that was not a reference. Only
1561references can be weakened.
1562
7896dde7
Z
1563=item Can't "when" outside a topicalizer
1564
1565(F) You have used a when() block that is neither inside a C<foreach>
1566loop nor a C<given> block. (Note that this error is issued on exit
1567from the C<when> block, so you won't get the error if the match fails,
1568or if you use an explicit C<continue>.)
1569
5f05dabc 1570=item Can't x= to read-only value
a0d0e21e 1571
be771a83
GS
1572(F) You tried to repeat a constant value (often the undefined value)
1573with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1574Perhaps you need to copy the value to a temporary, and repeat that.
1575
a04e6aad 1576=item Character following "\c" must be printable ASCII
f9d13529 1577
7357bd17 1578(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1579
727b6379 1580Note that ASCII characters that don't map to control characters are
7357bd17 1581discouraged, and will generate the warning (when enabled)
d4360efa 1582L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1583
163a633c
KW
1584=item Character following \%c must be '{' or a single-character Unicode property name in regex; marked by <-- HERE in m/%s/
1585
1586(F) (In the above the C<%c> is replaced by either C<p> or C<P>.) You
1587specified something that isn't a legal Unicode property name. Most
1588Unicode properties are specified by C<\p{...}>. But if the name is a
1589single character one, the braces may be omitted.
1590
f337b084 1591=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1592
1593(W pack) You said
1594
1595 pack("C", $x)
1596
1597where $x is either less than 0 or more than 255; the C<"C"> format is
1598only for encoding native operating system characters (ASCII, EBCDIC,
1599and so on) and not for Unicode characters, so Perl behaved as if you meant
1600
1601 pack("C", $x & 255)
1602
1603If you actually want to pack Unicode codepoints, use the C<"U"> format
1604instead.
1605
f337b084 1606=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1607
1608(W pack) You said
1609
1610 pack("c", $x)
1611
1612where $x is either less than -128 or more than 127; the C<"c"> format
1613is only for encoding native operating system characters (ASCII, EBCDIC,
1614and so on) and not for Unicode characters, so Perl behaved as if you meant
1615
1616 pack("c", $x & 255);
1617
1618If you actually want to pack Unicode codepoints, use the C<"U"> format
1619instead.
1620
f337b084
TH
1621=item Character in '%c' format wrapped in unpack
1622
1623(W unpack) You tried something like
1624
1625 unpack("H", "\x{2a1}")
1626
1a147d38 1627where the format expects to process a byte (a character with a value
6903afa2
FC
1628below 256), but a higher value was provided instead. Perl uses the
1629value modulus 256 instead, as if you had provided:
f337b084
TH
1630
1631 unpack("H", "\x{a1}")
1632
5a25739d
FC
1633=item Character in 'W' format wrapped in pack
1634
1635(W pack) You said
1636
1637 pack("U0W", $x)
1638
1639where $x is either less than 0 or more than 255. However, C<U0>-mode
1640expects all values to fall in the interval [0, 255], so Perl behaved
1641as if you meant:
1642
1643 pack("U0W", $x & 255)
1644
f337b084
TH
1645=item Character(s) in '%c' format wrapped in pack
1646
1647(W pack) You tried something like
1648
1649 pack("u", "\x{1f3}b")
1650
1a147d38 1651where the format expects to process a sequence of bytes (character with a
6903afa2 1652value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1653uses the character values modulus 256 instead, as if you had provided:
1654
1655 pack("u", "\x{f3}b")
1656
1657=item Character(s) in '%c' format wrapped in unpack
1658
1659(W unpack) You tried something like
1660
1661 unpack("s", "\x{1f3}b")
1662
1a147d38 1663where the format expects to process a sequence of bytes (character with a
6903afa2 1664value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1665uses the character values modulus 256 instead, as if you had provided:
1666
1667 unpack("s", "\x{f3}b")
1668
8d9d0498
FC
1669=item charnames alias definitions may not contain a sequence of multiple
1670spaces; marked by S<<-- HERE> in %s
f51551f7
FC
1671
1672(F) You defined a character name which had multiple space characters
1673in a row. Change them to single spaces. Usually these names are
1674defined in the C<:alias> import argument to C<use charnames>, but they
1675could be defined by a translator installed into C<$^H{charnames}>. See
1676L<charnames/CUSTOM ALIASES>.
1677
8d9d0498
FC
1678=item charnames alias definitions may not contain trailing white-space;
1679marked by S<<-- HERE> in %s
f51551f7
FC
1680
1681(F) You defined a character name which ended in a space
1682character. Remove the trailing space(s). Usually these names are
1683defined in the C<:alias> import argument to C<use charnames>, but they
1684could be defined by a translator installed into C<$^H{charnames}>.
1685See L<charnames/CUSTOM ALIASES>.
1686
60121127
TC
1687=item chdir() on unopened filehandle %s
1688
1689(W unopened) You tried chdir() on a filehandle that was never opened.
1690
d4360efa 1691=item "\c%c" is more clearly written simply as "%s"
f866a7cd 1692
d4360efa
S
1693(W syntax) The C<\cI<X>> construct is intended to be a way to specify
1694non-printable characters. You used it for a printable one, which
1695is better written as simply itself, perhaps preceded by a backslash
1696for non-word characters. Doing it the way you did is not portable
1697between ASCII and EBCDIC platforms.
f866a7cd 1698
6651ba0b
FC
1699=item Cloning substitution context is unimplemented
1700
1701(F) Creating a new thread inside the C<s///> operator is not supported.
1702
abc7ecad
SP
1703=item closedir() attempted on invalid dirhandle %s
1704
1705(W io) The dirhandle you tried to close is either closed or not really
1706a dirhandle. Check your control flow.
1707
5a25739d
FC
1708=item close() on unopened filehandle %s
1709
1710(W unopened) You tried to close a filehandle that was never opened.
1711
541ed3a9
FC
1712=item Closure prototype called
1713
1714(F) If a closure has attributes, the subroutine passed to an attribute
1715handler is the prototype that is cloned when a new closure is created.
1716This subroutine cannot be called.
1717
74d1b2e4
FC
1718=item \C no longer supported in regex; marked by S<<-- HERE> in m/%s/
1719
1720(F) The \C character class used to allow a match of single byte
1721within a multi-byte utf-8 character, but was removed in v5.24 as
1722it broke encapsulation and its implementation was extremely buggy.
1723If you really need to process the individual bytes, you probably
1724want to convert your string to one where each underlying byte is
1725stored as a character, with utf8::encode().
1726
49704364
LW
1727=item Code missing after '/'
1728
6903afa2
FC
1729(F) You had a (sub-)template that ends with a '/'. There must be
1730another template code following the slash. See L<perlfunc/pack>.
49704364 1731
c0236afe
KW
1732=item Code point 0x%X is not Unicode, and not portable
1733
dc4a6683 1734(S non_unicode portable) You had a code point that has never been in any
c0236afe 1735standard, so it is likely that languages other than Perl will NOT
dc4a6683
KW
1736understand it. This code point also will not fit in a 32-bit word on
1737ASCII platforms and therefore is non-portable between systems.
1738
1739At one time, it was legal in some standards to have code points up to
17400x7FFF_FFFF, but not higher, and this code point is higher.
c0236afe
KW
1741
1742Acceptance of these code points is a Perl extension, and you should
1743expect that nothing other than Perl can handle them; Perl itself on
1744EBCDIC platforms before v5.24 does not handle them.
1745
c0236afe
KW
1746Perl also makes no guarantees that the representation of these code
1747points won't change at some point in the future, say when machines
1748become available that have larger than a 64-bit word. At that time,
aaa9d2b4
KW
1749files containing any of these, written by an older Perl might require
1750conversion before being readable by a newer Perl.
c0236afe 1751
5a25739d
FC
1752=item Code point 0x%X is not Unicode, may not be portable
1753
2d88a86a 1754(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1755of U+10FFFF.
1756
c0236afe
KW
1757Perl allows strings to contain a superset of Unicode code points, but
1758these may not be accepted by other languages/systems. Further, even if
1759these languages/systems accept these large code points, they may have
1760chosen a different representation for them than the UTF-8-like one that
1761Perl has, which would mean files are not exchangeable between them and
1762Perl.
1763
1764On EBCDIC platforms, code points above 0x3FFF_FFFF have a different
1765representation in Perl v5.24 than before, so any file containing these
1766that was written before that version will require conversion before
1767being readable by a later Perl.
0876b9a0 1768
6df41af2
GS
1769=item %s: Command not found
1770
a892b81a 1771(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1772instead of Perl. Check the #! line, or manually feed your script into
1773Perl yourself. The #! line at the top of your file could look like
8f721816 1774
3bcfc7b3
LM
1775 #!/usr/bin/perl
1776
1777=item %s: command not found
1778
1779(A) You've accidentally run your script through B<bash> or another shell
1780instead of Perl. Check the #! line, or manually feed your script into
1781Perl yourself. The #! line at the top of your file could look like
1782
1783 #!/usr/bin/perl
1784
1785=item %s: command not found: %s
1786
1787(A) You've accidentally run your script through B<zsh> or another shell
1788instead of Perl. Check the #! line, or manually feed your script into
1789Perl yourself. The #! line at the top of your file could look like
1790
1791 #!/usr/bin/perl
6df41af2 1792
7a2e2cd6
PP
1793=item Compilation failed in require
1794
1795(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1796Perl uses this generic message when none of the errors that it
1797encountered were severe enough to halt compilation immediately.
7a2e2cd6 1798
c3464db5
DD
1799=item Complex regular subexpression recursion limit (%d) exceeded
1800
be771a83
GS
1801(W regexp) The regular expression engine uses recursion in complex
1802situations where back-tracking is required. Recursion depth is limited
1803to 32766, or perhaps less in architectures where the stack cannot grow
1804arbitrarily. ("Simple" and "medium" situations are handled without
1805recursion and are not subject to a limit.) Try shortening the string
1806under examination; looping in Perl code (e.g. with C<while>) rather than
1807in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1808that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1809on I<Mastering Regular Expressions>.)
c3464db5 1810
69282e91 1811=item connect() on closed socket %s
a0d0e21e 1812
be771a83
GS
1813(W closed) You tried to do a connect on a closed socket. Did you forget
1814to check the return value of your socket() call? See
1815L<perlfunc/connect>.
a0d0e21e 1816
e21e7c6a
FC
1817=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1818
1819(F) The subroutine registered to handle constant overloading
1820(see L<overload>) or a custom charnames handler (see
1821L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1822
1823=item Constant(%s): $^H{%s} is not defined
1824
1825(F) The parser found inconsistencies while attempting to define an
1826overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1827L<overload> pragma?
e21e7c6a 1828
779c5bc9
GS
1829=item Constant is not %s reference
1830
1831(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1832is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1833The message indicates the type of reference that was expected. This
be771a83 1834usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1835See L<perlsub/"Constant Functions"> and L<constant>.
1836
30fc7a28 1837=item Constants from lexical variables potentially modified elsewhere are no longer permitted
0ac016fc 1838
30fc7a28 1839(F) You wrote something like
0ac016fc
FC
1840
1841 my $var;
1842 $sub = sub () { $var };
1843
1844but $var is referenced elsewhere and could be modified after the C<sub>
1845expression is evaluated. Either it is explicitly modified elsewhere
1846(C<$var = 3>) or it is passed to a subroutine or to an operator like
1847C<printf> or C<map>, which may or may not modify the variable.
1848
1849Traditionally, Perl has captured the value of the variable at that
1850point and turned the subroutine into a constant eligible for inlining.
1851In those cases where the variable can be modified elsewhere, this
1852breaks the behavior of closures, in which the subroutine captures
1853the variable itself, rather than its value, so future changes to the
1854variable are reflected in the subroutine's return value.
1855
30fc7a28 1856This usage was deprecated, and as of Perl 5.32 is no longer allowed,
9840d1d6 1857making it possible to change the behavior in the future.
0ac016fc
FC
1858
1859If you intended for the subroutine to be eligible for inlining, then
1860make sure the variable is not referenced elsewhere, possibly by
1861copying it:
1862
1863 my $var2 = $var;
1864 $sub = sub () { $var2 };
1865
1866If you do want this subroutine to be a closure that reflects future
1867changes to the variable that it closes over, add an explicit C<return>:
1868
1869 my $var;
1870 $sub = sub () { return $var };
1871
4cee8e80
CS
1872=item Constant subroutine %s redefined
1873
aeb94125
FC
1874(W redefine)(S) You redefined a subroutine which had previously
1875been eligible for inlining. See L<perlsub/"Constant Functions">
1876for commentary and workarounds.
4cee8e80 1877
9607fc9c
PP
1878=item Constant subroutine %s undefined
1879
be771a83
GS
1880(W misc) You undefined a subroutine which had previously been eligible
1881for inlining. See L<perlsub/"Constant Functions"> for commentary and
1882workarounds.
9607fc9c 1883
5a25739d
FC
1884=item Constant(%s) unknown
1885
1886(F) The parser found inconsistencies either while attempting
1887to define an overloaded constant, or when trying to find the
1888character name specified in the C<\N{...}> escape. Perhaps you
3ee1a09c 1889forgot to load the corresponding L<overload> pragma?
5a25739d 1890
4a873d7a
FC
1891=item :const is experimental
1892
1893(S experimental::const_attr) The "const" attribute is experimental.
1894If you want to use the feature, disable the warning with C<no warnings
1895'experimental::const_attr'>, but know that in doing so you are taking
1896the risk that your code may break in a future Perl version.
1897
b77472f9
FC
1898=item :const is not permitted on named subroutines
1899
1900(F) The "const" attribute causes an anonymous subroutine to be run and
465068b9 1901its value captured at the time that it is cloned. Named subroutines are
b77472f9
FC
1902not cloned like this, so the attribute does not make sense on them.
1903
e7ea3e70
IZ
1904=item Copy method did not return a reference
1905
6903afa2 1906(F) The method which overloads "=" is buggy. See
13a2d996 1907L<overload/Copy Constructor>.
e7ea3e70 1908
4aaa4757
FC
1909=item &CORE::%s cannot be called directly
1910
1911(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1912with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1913in this package cannot yet be called that way, but must be
1914called as barewords. Something like this will work:
1915
1916 BEGIN { *shove = \&CORE::push; }
1917 shove @array, 1,2,3; # pushes on to @array
1918
6798c92b
GS
1919=item CORE::%s is not a keyword
1920
1921(F) The CORE:: namespace is reserved for Perl keywords.
1922
675fa9ff
FC
1923=item Corrupted regexp opcode %d > %d
1924
1925(P) This is either an error in Perl, or, if you're using
1926one, your L<custom regular expression engine|perlreapi>. If not the
8166b4e0 1927latter, report the problem to L<https://github.com/Perl/perl5/issues>.
675fa9ff 1928
a0d0e21e
LW
1929=item corrupted regexp pointers
1930
1931(P) The regular expression engine got confused by what the regular
1932expression compiler gave it.
1933
1934=item corrupted regexp program
1935
be771a83
GS
1936(P) The regular expression engine got passed a regexp program without a
1937valid magic number.
a0d0e21e 1938
de42a5a9 1939=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1940
1941(P) The malloc package that comes with Perl had an internal failure.
1942
49704364
LW
1943=item Count after length/code in unpack
1944
1945(F) You had an unpack template indicating a counted-length string, but
1946you have also specified an explicit size for the string. See
1947L<perlfunc/pack>.
1948
3f645a4e
FC
1949=item Declaring references is experimental
1950
1951(S experimental::declared_refs) This warning is emitted if you use
1952a reference constructor on the right-hand side of C<my>, C<state>, C<our>, or
1953C<local>. Simply suppress the warning if you want to use the feature, but
1954know that in doing so you are taking the risk of using an experimental
1955feature which may change or be removed in a future Perl version:
1956
1957 no warnings "experimental::declared_refs";
1958 use feature "declared_refs";
1959 $fooref = my \$foo;
1960
f2cccb4c
KW
1961=for comment
1962The following are used in lib/diagnostics.t for testing two =items that
1963share the same description. Changes here need to be propagated to there
1964
6651ba0b
FC
1965=item Deep recursion on anonymous subroutine
1966
a0d0e21e
LW
1967=item Deep recursion on subroutine "%s"
1968
be771a83
GS
1969(W recursion) This subroutine has called itself (directly or indirectly)
1970100 times more than it has returned. This probably indicates an
1971infinite recursion, unless you're writing strange benchmark programs, in
1972which case it indicates something else.
a0d0e21e 1973
aad1d01f
NC
1974This threshold can be changed from 100, by recompiling the F<perl> binary,
1975setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1976
e0e4a6e3
FC
1977=item (?(DEFINE)....) does not allow branches in regex; marked by
1978S<<-- HERE> in m/%s/
bcb95744 1979
6903afa2 1980(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1981most likely cause of this error is that you left out a parenthesis inside
1982of the C<....> part.
1983
6e8a73f2 1984The S<<-- HERE> shows whereabouts in the regular expression the problem was
bcb95744
FC
1985discovered.
1986
62658f4d
PM
1987=item %s defines neither package nor VERSION--version check failed
1988
1989(F) You said something like "use Module 42" but in the Module file
1990there are neither package declarations nor a C<$VERSION>.
1991
0ffcbc25
FC
1992=item delete argument is not a HASH or ARRAY element or slice
1993
4a0af295 1994(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1995such as:
1996
1997 $foo{$bar}
1998 $ref->{"susie"}[12]
1999
2000or a hash or array slice, such as:
2001
2002 @foo[$bar, $baz, $xyzzy]
2003 @{$ref->[12]}{"susie", "queue"}
2004
cc0776d6
DIM
2005or a hash key/value or array index/value slice, such as:
2006
2007 %foo[$bar, $baz, $xyzzy]
2008 %{$ref->[12]}{"susie", "queue"}
2009
fc36a67e
PP
2010=item Delimiter for here document is too long
2011
be771a83
GS
2012(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
2013long for Perl to handle. You have to be seriously twisted to write code
2014that triggers this error.
fc36a67e 2015
c437f7ac 2016=item Deprecated use of my() in false conditional. This will be a fatal error in Perl 5.30
6d3b25aa 2017
fa816bf3
FC
2018(D deprecated) You used a declaration similar to C<my $x if 0>. There
2019has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 2020not to be cleared at scope exit when its declaration includes a false
6903afa2 2021conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 2022static variable. Since we intend to fix this bug, we don't want people
6903afa2 2023relying on this behavior. You can achieve a similar static effect by
6d3b25aa 2024declaring the variable in a separate block outside the function, eg
36fb85f3 2025
6d3b25aa
RGS
2026 sub f { my $x if 0; return $x++ }
2027
2028becomes
2029
2030 { my $x; sub f { return $x++ } }
2031
ea9d9ebc 2032Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 2033lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
2034
2035 sub f { state $x; return $x++ }
2036
c437f7ac
A
2037This use of C<my()> in a false conditional has been deprecated since
2038Perl 5.10, and it will become a fatal error in Perl 5.30.
2039
500ab966
RGS
2040=item DESTROY created new reference to dead object '%s'
2041
2042(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
2043just being DESTROYed. Perl is confused, and prefers to abort rather
2044than to create a dangling reference.
500ab966 2045
3cdd684c
TP
2046=item Did not produce a valid header
2047
3de20fbe 2048See L</500 Server error>.
3cdd684c 2049
6df41af2
GS
2050=item %s did not return a true value
2051
2052(F) A required (or used) file must return a true value to indicate that
2053it compiled correctly and ran its initialization code correctly. It's
2054traditional to end such a file with a "1;", though any true value would
2055do. See L<perlfunc/require>.
2056
cc507455 2057=item (Did you mean &%s instead?)
4633a7c4 2058
413ff9f6
FC
2059(W misc) You probably referred to an imported subroutine &FOO as $FOO or
2060some such.
4633a7c4 2061
cc507455 2062=item (Did you mean "local" instead of "our"?)
33633739 2063
52e3acf8 2064(W shadow) Remember that "our" does not localize the declared global
be771a83
GS
2065variable. You have declared it again in the same lexical scope, which
2066seems superfluous.
33633739 2067
cc507455 2068=item (Did you mean $ or @ instead of %?)
a0d0e21e 2069
be771a83
GS
2070(W) You probably said %hash{$key} when you meant $hash{$key} or
2071@hash{@keys}. On the other hand, maybe you just meant %hash and got
2072carried away.
748a9306 2073
7e1af8bc 2074=item Died
5f05dabc
PP
2075
2076(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 2077you called it with no args and C<$@> was empty.
5f05dabc 2078
3cdd684c
TP
2079=item Document contains no data
2080
3de20fbe 2081See L</500 Server error>.
3cdd684c 2082
62658f4d
PM
2083=item %s does not define %s::VERSION--version check failed
2084
2085(F) You said something like "use Module 42" but the Module did not
943fc58e 2086define a C<$VERSION>.
62658f4d 2087
49704364
LW
2088=item '/' does not take a repeat count
2089
2090(F) You cannot put a repeat count of any kind right after the '/' code.
2091See L<perlfunc/pack>.
2092
1c99110e 2093=item do "%s" failed, '.' is no longer in @INC; did you mean do "./%s"?
2a0461a3 2094
b28683c9 2095(D deprecated) Previously C< do "somefile"; > would search the current
1c99110e
DM
2096directory for the specified file. Since perl v5.26.0, F<.> has been
2097removed from C<@INC> by default, so this is no longer true. To search the
2098current directory (and only the current directory) you can write
2099C< do "./somefile"; >.
2a0461a3 2100
95cb0d72
FC
2101=item Don't know how to get file name
2102
2103(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
2104somehow called on another platform. This should not happen.
2105
4021c788 2106=item Don't know how to handle magic of type \%o
a0d0e21e
LW
2107
2108(P) The internal handling of magical variables has been cursed.
2109
2110=item do_study: out of memory
2111
2112(P) This should have been caught by safemalloc() instead.
2113
6df41af2
GS
2114=item (Do you need to predeclare %s?)
2115
56da5a46
RGS
2116(S syntax) This is an educated guess made in conjunction with the message
2117"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
2118name is being referenced that hasn't been declared yet. This may be
2119because of ordering problems in your file, or because of a missing
be771a83
GS
2120"sub", "package", "require", or "use" statement. If you're referencing
2121something that isn't defined yet, you don't actually have to define the
2122subroutine or package before the current location. You can use an empty
2123"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 2124
d8ff3e95 2125=item dump() must be written as CORE::dump() as of Perl 5.30
ac206dc8 2126
d8ff3e95
JK
2127(F) You used the obsolete C<dump()> built-in function. That was deprecated in
2128Perl 5.8.0. As of Perl 5.30 it must be written in fully qualified format:
2129C<CORE::dump()>.
30b17cc1
A
2130
2131See L<perlfunc/dump>.
ac206dc8 2132
84d78eb7
YO
2133=item dump is not supported
2134
2135(F) Your machine doesn't support dump/undump.
2136
a0d0e21e
LW
2137=item Duplicate free() ignored
2138
be771a83
GS
2139(S malloc) An internal routine called free() on something that had
2140already been freed.
a0d0e21e 2141
1109a392
MHM
2142=item Duplicate modifier '%c' after '%c' in %s
2143
35f0cd76
FC
2144(W unpack) You have applied the same modifier more than once after a
2145type in a pack template. See L<perlfunc/pack>.
1109a392 2146
4633a7c4
LW
2147=item elseif should be elsif
2148
fa816bf3
FC
2149(S syntax) There is no keyword "elseif" in Perl because Larry thinks
2150it's ugly. Your code will be interpreted as an attempt to call a method
2151named "elseif" for the class returned by the following block. This is
4633a7c4
LW
2152unlikely to be what you want.
2153
c30c479a
KW
2154=item Empty \%c in regex; marked by S<<-- HERE> in m/%s/
2155
ccad8842
KW
2156=item Empty \%c{}
2157
e0e4a6e3 2158=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 2159
e750debb
KW
2160(F) You used something like C<\b{}>, C<\B{}>, C<\o{}>, C<\p>, C<\P>, or
2161C<\x> without specifying anything for it to operate on.
2162
2163Unfortunately, for backwards compatibility reasons, an empty C<\x> is
2164legal outside S<C<use re 'strict'>> and expands to a NUL character.
ab13f0c7 2165
d9a91485
KW
2166=item Empty (?) without any modifiers in regex; marked by <-- HERE in m/%s/
2167
2168(W regexp) (only under C<S<use re 'strict'>>)
2169C<(?)> does nothing, so perhaps this is a typo.
2170
fd503f5c 2171=item ${^ENCODING} is no longer supported
a15a3d9b 2172
fd503f5c 2173(F) The special variable C<${^ENCODING}>, formerly used to implement
a15a3d9b
FC
2174the C<encoding> pragma, is no longer supported as of Perl 5.26.0.
2175
fd503f5c
DIM
2176Setting it to anything other than C<undef> is a fatal error as of Perl
21775.28.
ac641426 2178
85ab1d1d 2179=item entering effective %s failed
5ff3f7a4 2180
85ab1d1d 2181(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2182effective uids or gids failed.
2183
c038024b
RGS
2184=item %ENV is aliased to %s
2185
2186(F) You're running under taint mode, and the C<%ENV> variable has been
2187aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 2188program's environment. This is potentially insecure.
c038024b 2189
748a9306
LW
2190=item Error converting file specification %s
2191
5f05dabc 2192(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 2193specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
2194single form when it must operate on them directly. Either you've passed
2195an invalid file specification to Perl, or you've found a case the
2196conversion routines don't handle. Drat.
748a9306 2197
ad19ef22 2198=item Eval-group in insecure regular expression
e4d48cc9 2199
be771a83
GS
2200(F) Perl detected tainted data when trying to compile a regular
2201expression that contains the C<(?{ ... })> zero-width assertion, which
2202is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 2203
ad19ef22 2204=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 2205
be771a83
GS
2206(F) Perl tried to compile a regular expression containing the
2207C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
2208pattern contains interpolated values. Since that is a security risk,
2209it is not allowed. If you insist, you may still do this by using the
2210C<re 'eval'> pragma or by explicitly building the pattern from an
2211interpolated string at run time and using that in an eval(). See
2212L<perlre/(?{ code })>.
e4d48cc9 2213
ad19ef22 2214=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 2215
be771a83
GS
2216(F) A regular expression contained the C<(?{ ... })> zero-width
2217assertion, but that construct is only allowed when the C<use re 'eval'>
2218pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 2219
e0e4a6e3
FC
2220=item EVAL without pos change exceeded limit in regex; marked by
2221S<<-- HERE> in m/%s/
1a147d38
YO
2222
2223(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 2224any text. Restructure the pattern so that text is consumed.
1a147d38 2225
6e8a73f2 2226The S<<-- HERE> shows whereabouts in the regular expression the problem was
1a147d38
YO
2227discovered.
2228
fc36a67e
PP
2229=item Excessively long <> operator
2230
2231(F) The contents of a <> operator may not exceed the maximum size of a
2232Perl identifier. If you're just trying to glob a long list of
2233filenames, try using the glob() operator, or put the filenames into a
2234variable and glob that.
2235
ed9aa3b7
SG
2236=item exec? I'm not *that* kind of operating system
2237
af8bb25a 2238(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 2239OS. See L<perlport>.
ed9aa3b7 2240
c77da5ff 2241=item %sExecution of %s aborted due to compilation errors.
a0d0e21e
LW
2242
2243(F) The final summary message when a Perl compilation fails.
2244
0ffcbc25
FC
2245=item exists argument is not a HASH or ARRAY element or a subroutine
2246
4a0af295 2247(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
2248subroutine with an ampersand, such as:
2249
2250 $foo{$bar}
2251 $ref->{"susie"}[12]
2252 &do_something
2253
2254=item exists argument is not a subroutine name
2255
ccfc2567
FC
2256(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
2257and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 2258
a0d0e21e
LW
2259=item Exiting eval via %s
2260
be771a83
GS
2261(W exiting) You are exiting an eval by unconventional means, such as a
2262goto, or a loop control statement.
e476b1b5
GS
2263
2264=item Exiting format via %s
2265
9a2ff54b 2266(W exiting) You are exiting a format by unconventional means, such as a
be771a83 2267goto, or a loop control statement.
a0d0e21e 2268
0a753a76
PP
2269=item Exiting pseudo-block via %s
2270
be771a83
GS
2271(W exiting) You are exiting a rather special block construct (like a
2272sort block or subroutine) by unconventional means, such as a goto, or a
2273loop control statement. See L<perlfunc/sort>.
0a753a76 2274
a0d0e21e
LW
2275=item Exiting subroutine via %s
2276
be771a83
GS
2277(W exiting) You are exiting a subroutine by unconventional means, such
2278as a goto, or a loop control statement.
a0d0e21e
LW
2279
2280=item Exiting substitution via %s
2281
be771a83
GS
2282(W exiting) You are exiting a substitution by unconventional means, such
2283as a return, a goto, or a loop control statement.
a0d0e21e 2284
e0e4a6e3 2285=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 2286
675fa9ff 2287(F) You wrote something like
c608e803
KW
2288
2289 (?13
2290
2291to denote a capturing group of the form
2292L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
2293but omitted the C<")">.
2294
d8d1dede
KW
2295=item Expecting interpolated extended charclass in regex; marked by <--
2296HERE in m/%s/
c9ffefcc 2297
d8d1dede
KW
2298(F) It looked like you were attempting to interpolate an
2299already-compiled extended character class, like so:
c9ffefcc 2300
d8d1dede
KW
2301 my $thai_or_lao = qr/(?[ \p{Thai} + \p{Lao} ])/;
2302 ...
2303 qr/(?[ \p{Digit} & $thai_or_lao ])/;
c9ffefcc 2304
d8d1dede
KW
2305But the marked code isn't syntactically correct to be such an
2306interpolated class.
27350048 2307
baabe3fb 2308=item Experimental aliasing via reference not enabled
1f8155a2 2309
baabe3fb 2310(F) To do aliasing via references, you must first enable the feature:
1f8155a2 2311
baabe3fb
FC
2312 no warnings "experimental::refaliasing";
2313 use feature "refaliasing";
1f8155a2
FC
2314 \$x = \$y;
2315
74d1b2e4
FC
2316=item Experimental %s on scalar is now forbidden
2317
2318(F) An experimental feature added in Perl 5.14 allowed C<each>, C<keys>,
2319C<push>, C<pop>, C<shift>, C<splice>, C<unshift>, and C<values> to be called with a
2320scalar argument. This experiment is considered unsuccessful, and
2321has been removed. The C<postderef> feature may meet your needs better.
2322
30d9c59b
Z
2323=item Experimental subroutine signatures not enabled
2324
2325(F) To use subroutine signatures, you must first enable them:
2326
caa35032 2327 no warnings "experimental::signatures";
30d9c59b
Z
2328 use feature "signatures";
2329 sub foo ($left, $right) { ... }
2330
7b8d334a
GS
2331=item Explicit blessing to '' (assuming package main)
2332
be771a83
GS
2333(W misc) You are blessing a reference to a zero length string. This has
2334the effect of blessing the reference into the package main. This is
2335usually not what you want. Consider providing a default target package,
2336e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2337
6df41af2
GS
2338=item %s: Expression syntax
2339
be771a83
GS
2340(A) You've accidentally run your script through B<csh> instead of Perl.
2341Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2342
2343=item %s failed--call queue aborted
2344
3c10abe3
AG
2345(F) An untrapped exception was raised while executing a UNITCHECK,
2346CHECK, INIT, or END subroutine. Processing of the remainder of the
2347queue of such routines has been prematurely ended.
6df41af2 2348
e0d4aead 2349=item Failed to close in-place work file %s: %s
502aca56
TC
2350
2351(F) Closing an output file from in-place editing, as with the C<-i>
2352command-line switch, failed.
2353
e0e4a6e3 2354=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2355
98d31c73 2356(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2357character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2358in your false range is interpreted as a literal "-". In a C<(?[...])>
2359construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2360the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2361the problem was discovered. See L<perlre>.
73b437c8 2362
1b1ee2ef 2363=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2364
be771a83
GS
2365(P) An error peculiar to VMS. Something untoward happened in a VMS
2366system service or RTL routine; Perl's exit status should provide more
2367details. The filename in "at %s" and the line number in "line %d" tell
2368you which section of the Perl source code is distressed.
a0d0e21e
LW
2369
2370=item fcntl is not implemented
2371
2372(F) Your machine apparently doesn't implement fcntl(). What is this, a
2373PDP-11 or something?
2374
22846ab4
AB
2375=item FETCHSIZE returned a negative value
2376
2377(F) A tied array claimed to have a negative number of elements, which
2378is not possible.
2379
f337b084
TH
2380=item Field too wide in 'u' format in pack
2381
d8b5cc61 2382(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2383which can't encode values above 63. So there is no point in asking for
2384a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2385C<u63> as the format.
f337b084 2386
a0e213fc
A
2387=item File::Glob::glob() will disappear in perl 5.30. Use File::Glob::bsd_glob() instead.
2388
2389(D deprecated) C<< File::Glob >> has a function called C<< glob >>, which
2390just calls C<< bsd_glob >>. However, its prototype is different from the
2391prototype of C<< CORE::glob >>, and hence, C<< File::Glob::glob >> should
2392not be used.
2393
2394C<< File::Glob::glob() >> was deprecated in perl 5.8.0. A deprecation
2395message was issued from perl 5.26.0 onwards, and the function will
2396disappear in perl 5.30.0.
2397
2398Code using C<< File::Glob::glob() >> should call
2399C<< File::Glob::bsd_glob() >> instead.
2400
af8c498a 2401=item Filehandle %s opened only for input
a0d0e21e 2402
6c8d78fb
HS
2403(W io) You tried to write on a read-only filehandle. If you intended
2404it to be a read-write filehandle, you needed to open it with "+<" or
2405"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2406write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2407
af8c498a 2408=item Filehandle %s opened only for output
a0d0e21e 2409
6c8d78fb
HS
2410(W io) You tried to read from a filehandle opened only for writing, If
2411you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2412with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2413read from the file, use "<". See L<perlfunc/open>. Another possibility
2414is that you attempted to open filedescriptor 0 (also known as STDIN) for
2415output (maybe you closed STDIN earlier?).
97828cef
RGS
2416
2417=item Filehandle %s reopened as %s only for input
2418
2419(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2420as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2421previously.
2422
2423=item Filehandle STDIN reopened as %s only for output
2424
2425(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2426as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2427
2428=item Final $ should be \$ or $name
2429
2430(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2431a literal dollar sign, or was meant to introduce a variable name that
2432happens to be missing. So you have to put either the backslash or the
2433name.
a0d0e21e 2434
56e90b21
GS
2435=item flock() on closed filehandle %s
2436
be771a83 2437(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2438some time before now. Check your control flow. flock() operates on
be771a83
GS
2439filehandles. Are you attempting to call flock() on a dirhandle by the
2440same name?
56e90b21 2441
6df41af2
GS
2442=item Format not terminated
2443
2444(F) A format must be terminated by a line with a solitary dot. Perl got
2445to the end of your file without finding such a line.
2446
a0d0e21e
LW
2447=item Format %s redefined
2448
e476b1b5 2449(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2450
2451 {
271595cc 2452 no warnings 'redefine';
a0d0e21e
LW
2453 eval "format NAME =...";
2454 }
2455
a0d0e21e
LW
2456=item Found = in conditional, should be ==
2457
e476b1b5 2458(W syntax) You said
a0d0e21e
LW
2459
2460 if ($foo = 123)
2461
2462when you meant
2463
2464 if ($foo == 123)
2465
2466(or something like that).
2467
6df41af2
GS
2468=item %s found where operator expected
2469
56da5a46
RGS
2470(S syntax) The Perl lexer knows whether to expect a term or an operator.
2471If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2472operator, it gives you this warning. Usually it indicates that an
2473operator or delimiter was omitted, such as a semicolon.
6df41af2 2474
a0d0e21e
LW
2475=item gdbm store returned %d, errno %d, key "%s"
2476
2477(S) A warning from the GDBM_File extension that a store failed.
2478
2479=item gethostent not implemented
2480
2481(F) Your C library apparently doesn't implement gethostent(), probably
2482because if it did, it'd feel morally obligated to return every hostname
2483on the Internet.
2484
69282e91 2485=item get%sname() on closed socket %s
a0d0e21e 2486
be771a83
GS
2487(W closed) You tried to get a socket or peer socket name on a closed
2488socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2489
748a9306
LW
2490=item getpwnam returned invalid UIC %#o for user "%s"
2491
2492(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2493C<getpwnam> operator returned an invalid UIC.
2494
6df41af2
GS
2495=item getsockopt() on closed socket %s
2496
be771a83
GS
2497(W closed) You tried to get a socket option on a closed socket. Did you
2498forget to check the return value of your socket() call? See
6df41af2
GS
2499L<perlfunc/getsockopt>.
2500
0f539b13
BF
2501=item given is experimental
2502
7896dde7
Z
2503(S experimental::smartmatch) C<given> depends on smartmatch, which
2504is experimental, so its behavior may change or even be removed
2505in any future release of perl. See the explanation under
2506L<perlsyn/Experimental Details on given and when>.
0f539b13 2507
68567d27
FC
2508=item Global symbol "%s" requires explicit package name (did you forget to
2509declare "my %s"?)
6df41af2 2510
a4edf47d 2511(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2512that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2513declared beforehand using "our", or explicitly qualified to say
2514which package the global variable is in (using "::").
6df41af2 2515
e476b1b5
GS
2516=item glob failed (%s)
2517
5ead438e 2518(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2519for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2520pattern that caused the external program to fail and exit with a
be771a83 2521nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2522resulted in a coredump, this may also mean that your csh (C shell)
2523is broken. If so, you should change all of the csh-related variables
2524in config.sh: If you have tcsh, make the variables refer to it as
2525if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2526all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2527think csh is missing. In either case, after editing config.sh, run
75b44862 2528C<./Configure -S> and rebuild Perl.
e476b1b5 2529
a0d0e21e
LW
2530=item Glob not terminated
2531
2532(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2533a term, so it's looking for the corresponding right angle bracket, and
2534not finding it. Chances are you left some needed parentheses out
2535earlier in the line, and you really meant a "less than".
a0d0e21e 2536
b35b96b6
JH
2537=item gmtime(%f) failed
2538
2539(W overflow) You called C<gmtime> with a number that it could not handle:
2540too large, too small, or NaN. The returned value is C<undef>.
2541
bcd05b94 2542=item gmtime(%f) too large
8b56d6ff 2543
e9200be3 2544(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2545it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2546date. This warning is also triggered with NaN (the special
fc003d4b
MS
2547not-a-number value).
2548
bcd05b94 2549=item gmtime(%f) too small
fc003d4b 2550
e9200be3 2551(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2552it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2553
6df41af2 2554=item Got an error from DosAllocMem
a0d0e21e 2555
6df41af2
GS
2556(P) An error peculiar to OS/2. Most probably you're using an obsolete
2557version of Perl, and this should not happen anyway.
a0d0e21e
LW
2558
2559=item goto must have label
2560
2561(F) Unlike with "next" or "last", you're not allowed to goto an
2562unspecified destination. See L<perlfunc/goto>.
2563
6651ba0b
FC
2564=item Goto undefined subroutine%s
2565
2566(F) You tried to call a subroutine with C<goto &sub> syntax, but
2567the indicated subroutine hasn't been defined, or if it was, it
2568has since been undefined.
2569
6fbc9859 2570=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2571S<<-- HERE> in m/%s/
1f4f6bf1
YO
2572
2573(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2574they must start with a non-digit word character. A common cause of
2575this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2576
5a25739d
FC
2577=item ()-group starts with a count
2578
2579(F) A ()-group started with a count. A count is supposed to follow
2580something: a template character or a ()-group. See L<perlfunc/pack>.
2581
fe13d51d 2582=item %s had compilation errors.
6df41af2
GS
2583
2584(F) The final summary message when a C<perl -c> fails.
2585
a0d0e21e
LW
2586=item Had to create %s unexpectedly
2587
be771a83
GS
2588(S internal) A routine asked for a symbol from a symbol table that ought
2589to have existed already, but for some reason it didn't, and had to be
2590created on an emergency basis to prevent a core dump.
a0d0e21e 2591
6df41af2
GS
2592=item %s has too many errors
2593
2594(F) The parser has given up trying to parse the program after 10 errors.
2595Further error messages would likely be uninformative.
2596
61e61fbc
JH
2597=item Hexadecimal float: exponent overflow
2598
d8f2b442 2599(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2600than the floating point supports.
2601
2602=item Hexadecimal float: exponent underflow
2603
d8f2b442 2604(W overflow) The hexadecimal floating point has a smaller exponent
b6d9b423
JH
2605than the floating point supports. With the IEEE 754 floating point,
2606this may also mean that the subnormals (formerly known as denormals)
2607are being used, which may or may not be an error.
61e61fbc 2608
5488d373 2609=item Hexadecimal float: internal error (%s)
cf4f6003
JH
2610
2611(F) Something went horribly bad in hexadecimal float handling.
2612
61e61fbc
JH
2613=item Hexadecimal float: mantissa overflow
2614
2615(W overflow) The hexadecimal floating point literal had more bits in
2616the mantissa (the part between the 0x and the exponent, also known as
2617the fraction or the significand) than the floating point supports.
2618
40bca5ae
JH
2619=item Hexadecimal float: precision loss
2620
2621(W overflow) The hexadecimal floating point had internally more
2622digits than could be output. This can be caused by unsupported
2623long double formats, or by 64-bit integers not being available
2624(needed to retrieve the digits under some configurations).
2625
2626=item Hexadecimal float: unsupported long double format
2627
2628(F) You have configured Perl to use long doubles but
d8f2b442 2629the internals of the long double format are unknown;
40bca5ae
JH
2630therefore the hexadecimal float output is impossible.
2631
252aa082
JH
2632=item Hexadecimal number > 0xffffffff non-portable
2633
e476b1b5 2634(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2635(4294967295) and therefore non-portable between systems. See
2636L<perlport> for more on portability concerns.
252aa082 2637
8903cb82
PP
2638=item Identifier too long
2639
2640(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2641about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2642names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2643of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2644
e0e4a6e3
FC
2645=item Ignoring zero length \N{} in character class in regex; marked by
2646S<<-- HERE> in m/%s/
fc8cd66c 2647
f3ba6905 2648(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
0f44b2a5
FC
2649zero-length sequence. When such an escape is used in a character
2650class its behavior is not well defined. Check that the correct
2651escape has been used, and the correct charname handler is in scope.
fc8cd66c 2652
bcfb98ec 2653=item Illegal %s digit '%c' ignored
f675dbe5 2654
bcfb98ec
KW
2655(W digit) Here C<%s> is one of "binary", "octal", or "hex".
2656You may have tried to use a digit other than one that is legal for the
2657given type, such as only 0 and 1 for binary. For octals, this is raised
2658only if the illegal character is an '8' or '9'. For hex, 'A' - 'F' and
2659'a' - 'f' are legal.
2660Interpretation of the number stopped just before the offending digit or
2661character.
f675dbe5 2662
bcfb98ec 2663=item Illegal binary digit '%c'
a0d0e21e 2664
bcfb98ec 2665(F) You used a digit other than 0 or 1 in a binary number.
a0d0e21e 2666
6597eb22
FC
2667=item Illegal character after '_' in prototype for %s : %s
2668
e4d150f1
FC
2669(W illegalproto) An illegal character was found in a prototype
2670declaration. The '_' in a prototype must be followed by a ';',
2671indicating the rest of the parameters are optional, or one of '@'
2672or '%', since those two will accept 0 or more final parameters.
6597eb22 2673
b913d0b8
FC
2674=item Illegal character \%o (carriage return)
2675
2676(F) Perl normally treats carriage returns in the program text as
2677it would any other whitespace, which means you should never see
2678this error when Perl was built using standard options. For some
2679reason, your version of Perl appears to have been built without
2680this support. Talk to your Perl administrator.
2681
bb6b75cd 2682=item Illegal character following sigil in a subroutine signature
d3d9da4a
DM
2683
2684(F) A parameter in a subroutine signature contained an unexpected character
d4e5761f
FC
2685following the C<$>, C<@> or C<%> sigil character. Normally the sigil
2686should be followed by the variable name or C<=> etc. Perhaps you are
d3d9da4a
DM
2687trying use a prototype while in the scope of C<use feature 'signatures'>?
2688For example:
2689
2690 sub foo ($$) {} # legal - a prototype
2691
2692 use feature 'signatures;
2693 sub foo ($$) {} # illegal - was expecting a signature
2694 sub foo ($a, $b)
2695 :prototype($$) {} # legal
2696
2697
d37a9538
ST
2698=item Illegal character in prototype for %s : %s
2699
197afce1 2700(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2701Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2702Perhaps you were trying to write a subroutine signature but didn't enable
2703that feature first (C<use feature 'signatures'>), so your signature was
2704instead interpreted as a bad prototype.
d37a9538 2705
904d85c5
RGS
2706=item Illegal declaration of anonymous subroutine
2707
2708(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2709you must always specify a block of code. See L<perlsub>.
904d85c5 2710
8e742a20
MHM
2711=item Illegal declaration of subroutine %s
2712
6903afa2 2713(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2714
a0d0e21e
LW
2715=item Illegal division by zero
2716
be771a83
GS
2717(F) You tried to divide a number by 0. Either something was wrong in
2718your logic, or you need to put a conditional in to guard against
2719meaningless input.
a0d0e21e
LW
2720
2721=item Illegal modulus zero
2722
be771a83
GS
2723(F) You tried to divide a number by 0 to get the remainder. Most
2724numbers don't take to this kindly.
a0d0e21e 2725
6df41af2 2726=item Illegal number of bits in vec
399388f4 2727
6df41af2
GS
2728(F) The number of bits in vec() (the third argument) must be a power of
2729two from 1 to 32 (or 64, if your platform supports that).
399388f4 2730
283151b7 2731=item Illegal octal digit '%c'
a0d0e21e 2732
d1be9408 2733(F) You used an 8 or 9 in an octal number.
a0d0e21e 2734
ecc6274e
FC
2735=item Illegal operator following parameter in a subroutine signature
2736
2737(F) A parameter in a subroutine signature, was followed by something
2738other than C<=> introducing a default, C<,> or C<)>.
2739
2740 use feature 'signatures';
2741 sub foo ($=1) {} # legal
2742 sub foo ($a = 1) {} # legal
2743 sub foo ($a += 1) {} # illegal
2744 sub foo ($a == 1) {} # illegal
2745
e0e4a6e3 2746=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2747
675fa9ff 2748(F) You wrote something like
c608e803
KW
2749
2750 (?+foo)
2751
2752The C<"+"> is valid only when followed by digits, indicating a
2753capturing group. See
2754L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2755
375ed12a
JH
2756=item Illegal suidscript
2757
2758(F) The script run under suidperl was somehow illegal.
2759
fe13d51d 2760=item Illegal switch in PERL5OPT: -%c
6ff81951 2761
6df41af2 2762(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2763following switches: B<-[CDIMUdmtw]>.
6ff81951 2764
4003ea29
KW
2765=item Illegal user-defined property name
2766
2767(F) You specified a Unicode-like property name in a regular expression
2768pattern (using C<\p{}> or C<\P{}>) that Perl knows isn't an official
2769Unicode property, and was likely meant to be a user-defined property
2770name, but it can't be one of those, as they must begin with either C<In>
2771or C<Is>. Check the spelling. See also
2772L</Can't find Unicode property definition "%s">.
2773
6df41af2 2774=item Ill-formed CRTL environ value "%s"
81e118e0 2775
75b44862 2776(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2777internal environ array, and encountered an element without the C<=>
2778delimiter used to separate keys from values. The element is ignored.
09bef843 2779
6df41af2 2780=item Ill-formed message in prime_env_iter: |%s|
54310121 2781
be771a83
GS
2782(W internal) A warning peculiar to VMS. Perl tried to read a logical
2783name or CLI symbol definition when preparing to iterate over %ENV, and
2784didn't see the expected delimiter between key and value, so the line was
2785ignored.
54310121 2786
6df41af2 2787=item (in cleanup) %s
9607fc9c 2788
be771a83
GS
2789(W misc) This prefix usually indicates that a DESTROY() method raised
2790the indicated exception. Since destructors are usually called by the
2791system at arbitrary points during execution, and often a vast number of
2792times, the warning is issued only once for any number of failures that
2793would otherwise result in the same message being repeated.
6df41af2 2794
be771a83
GS
2795Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2796also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2797
e0e4a6e3
FC
2798=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2799in m/%s/
0d0b4b3b 2800
675fa9ff 2801(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2802expression inside the construct was completely empty, or if there are
2803too many or few operands for the number of operators. Perl is not smart
2804enough to give you a more precise indication as to what is wrong.
2805
6fbc9859
MH
2806=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2807parent '%s'
2c7d6b9c
RGS
2808
2809(F) The method resolution order (MRO) of the given class is not
2810C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2811documentation in L<mro> for more information.
2812
cdd6375d
MH
2813=item Indentation on line %d of here-doc doesn't match delimiter
2814
2815(F) You have an indented here-document where one or more of its lines
2816have whitespace at the beginning that does not match the closing
2817delimiter.
2818
2819For example, line 2 below is wrong because it does not have at least
28202 spaces, but lines 1 and 3 are fine because they have at least 2:
2821
2822 if ($something) {
2823 print <<~EOF;
2824 Line 1
2825 Line 2 not
2826 Line 3
2827 EOF
2828 }
2829
2830Note that tabs and spaces are compared strictly, meaning 1 tab will
2831not match 8 spaces.
2832
6a2ed79a 2833=item Infinite recursion in regex
1a147d38
YO
2834
2835(F) You used a pattern that references itself without consuming any input
6903afa2 2836text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2837either consume text or fail.
2838
714f94d1
FC
2839=item Infinite recursion via empty pattern
2840
2841(F) You tried to use the empty pattern inside of a regex code block,
2842for instance C</(?{ s!!! })/>, which resulted in re-executing
2843the same pattern, which is an infinite loop which is broken by
2844throwing an exception.
2845
f99042c8 2846=item Initialization of state variables in list currently forbidden
6dbe9451 2847
f99042c8
Z
2848(F) C<state> only permits initializing a single variable, specified
2849without parentheses. So C<state $a = 42> and C<state @a = qw(a b c)> are
2850allowed, but not C<state ($a) = 42> or C<(state $a) = 42>. To initialize
2851more than one C<state> variable, initialize them one at a time.
6dbe9451 2852
2186f873
FC
2853=item %%s[%s] in scalar context better written as $%s[%s]
2854
2855(W syntax) In scalar context, you've used an array index/value slice
2856(indicated by %) to select a single element of an array. Generally
2857it's better to ask for a scalar value (indicated by $). The difference
2858is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2859returns and when evaluating its argument, while C<%foo[&bar]> provides
2860a list context to its subscript, which can do weird things if you're
2861expecting only one subscript. When called in list context, it also
2862returns the index (what C<&bar> returns) in addition to the value.
2863
2864=item %%s{%s} in scalar context better written as $%s{%s}
2865
2866(W syntax) In scalar context, you've used a hash key/value slice
2867(indicated by %) to select a single element of a hash. Generally it's
2868better to ask for a scalar value (indicated by $). The difference
2869is that C<$foo{&bar}> always behaves like a scalar, both in the value
2870it returns and when evaluating its argument, while C<@foo{&bar}> and
2871provides a list context to its subscript, which can do weird things
2872if you're expecting only one subscript. When called in list context,
2873it also returns the key in addition to the value.
2874
a0d0e21e
LW
2875=item Insecure dependency in %s
2876
8b1a09fc 2877(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2878The tainting mechanism is turned on when you're running setuid or
2879setgid, or when you specify B<-T> to turn it on explicitly. The
2880tainting mechanism labels all data that's derived directly or indirectly
2881from the user, who is considered to be unworthy of your trust. If any
2882such data is used in a "dangerous" operation, you get this error. See
2883L<perlsec> for more information.
a0d0e21e
LW
2884
2885=item Insecure directory in %s
2886
be771a83
GS
2887(F) You can't use system(), exec(), or a piped open in a setuid or
2888setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2889the world. Also, the PATH must not contain any relative directory.
2890See L<perlsec>.
a0d0e21e 2891
62f468fc 2892=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2893
2894(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2895setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2896C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2897supplied (or potentially supplied) by the user. The script must set
2898the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2899
0e9be77f
DM
2900=item Insecure user-defined property %s
2901
2902(F) Perl detected tainted data when trying to compile a regular
2903expression that contains a call to a user-defined character property
2904function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2905See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2906
b9ef414d
FC
2907=item Integer overflow in format string for %s
2908
2909(F) The indexes and widths specified in the format string of C<printf()>
2910or C<sprintf()> are too large. The numbers must not overflow the size of
2911integers for your architecture.
2912
a7ae9550
GS
2913=item Integer overflow in %s number
2914
35928bc5 2915(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2916either as a literal or as an argument to hex() or oct() is too big for
2917your architecture, and has been converted to a floating point number.
2918On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2919representable without overflow is 0xFFFFFFFF, 037777777777, or
29200b11111111111111111111111111111111 respectively. Note that Perl
2921transparently promotes all numbers to a floating point representation
2922internally--subject to loss of precision errors in subsequent
2923operations.
bbce6d69 2924
fc89ca81
FC
2925=item Integer overflow in srand
2926
2927(S overflow) The number you have passed to srand is too big to fit
2928in your architecture's integer representation. The number has been
2929replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2930architectures). This means you may be getting less randomness than
2931you expect, because different random seeds above the maximum will
2932return the same sequence of random numbers.
2933
46314c13
JP
2934=item Integer overflow in version
2935
18da5252
FC
2936=item Integer overflow in version %d
2937
784d71ed
FC
2938(W overflow) Some portion of a version initialization is too large for
2939the size of integers for your architecture. This is not a warning
f084e84f 2940because there is no rational reason for a version to try and use an
784d71ed
FC
2941element larger than typically 2**32. This is usually caused by trying
2942to use some odd mathematical operation as a version, like 100/9.
46314c13 2943
e0e4a6e3 2944=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2945
2946(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2947The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2948discovered.
2949
748a9306
LW
2950=item Internal inconsistency in tracking vforks
2951
be771a83
GS
2952(S) A warning peculiar to VMS. Perl keeps track of the number of times
2953you've called C<fork> and C<exec>, to determine whether the current call
2954to C<exec> should affect the current script or a subprocess (see
2955L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2956Perl is making a guess and treating this C<exec> as a request to
2957terminate the Perl script and execute the specified command.
748a9306 2958
870978ae
FC
2959=item internal %<num>p might conflict with future printf extensions
2960
2961(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2962formatting follows a slightly different set of rules when called from
2963C or XS code. Specifically, formats consisting of digits followed
2964by "p" (e.g., "%7p") are reserved for future use. If you see this
2965message, then an XS module tried to call that routine with one such
2966reserved format.
2967
e0e4a6e3 2968=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2969
fa816bf3 2970(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2971S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2972discovered.
a0d0e21e 2973
6df41af2
GS
2974=item %s (...) interpreted as function
2975
75b44862 2976(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2977followed by parentheses turns into a function, with all the list
64977eb6 2978operators arguments found inside the parentheses. See
13a2d996 2979L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2980
f51551f7
FC
2981=item In '(?...)', the '(' and '?' must be adjacent in regex;
2982marked by S<<-- HERE> in m/%s/
2983
2984(F) The two-character sequence C<"(?"> in this context in a regular
2985expression pattern should be an indivisible token, with nothing
2986intervening between the C<"("> and the C<"?">, but you separated them
2987with whitespace.
2988
d9790612 2989=item In '(*...)', the '(' and '*' must be adjacent in regex;
edf23316
FC
2990marked by S<<-- HERE> in m/%s/
2991
d9790612 2992(F) The two-character sequence C<"(*"> in this context in a regular
edf23316 2993expression pattern should be an indivisible token, with nothing
d9790612
KW
2994intervening between the C<"("> and the C<"*">, but you separated them.
2995Fix the pattern and retry.
edf23316 2996
09bef843
SB
2997=item Invalid %s attribute: %s
2998
a4a4c9e2 2999(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
3000by Perl or by a user-supplied handler. See L<attributes>.
3001
3002=item Invalid %s attributes: %s
3003
a4a4c9e2 3004(F) The indicated attributes for a subroutine or variable were not
be771a83 3005recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 3006
e0e4a6e3
FC
3007=item Invalid character in charnames alias definition; marked by
3008S<<-- HERE> in '%s
225fb84f
KW
3009
3010(F) You tried to create a custom alias for a character name, with
3011the C<:alias> option to C<use charnames> and the specified character in
3012the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
3013
c8028aa6
TC
3014=item Invalid \0 character in %s for %s: %s\0%s
3015
fa3234e3
FC
3016(W syscalls) Embedded \0 characters in pathnames or other system call
3017arguments produce a warning as of 5.20. The parts after the \0 were
3018formerly ignored by system calls.
c8028aa6 3019
e0e4a6e3 3020=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
3021
3022(F) Only certain characters are valid for character names. The
3023indicated one isn't. See L<charnames/CUSTOM ALIASES>.
3024
c635e13b
PP
3025=item Invalid conversion in %s: "%s"
3026
be771a83
GS
3027(W printf) Perl does not understand the given format conversion. See
3028L<perlfunc/sprintf>.
c635e13b 3029
e0e4a6e3
FC
3030=item Invalid escape in the specified encoding in regex; marked by
3031S<<-- HERE> in m/%s/
9e08bc66 3032
98d31c73 3033(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
3034didn't correspond to a single character through the conversion
3035from the encoding specified by the encoding pragma.
98d31c73
FC
3036The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
3037instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 3038The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
3039escape was discovered.
3040
8149aa9f
FC
3041=item Invalid hexadecimal number in \N{U+...}
3042
e0e4a6e3
FC
3043=item Invalid hexadecimal number in \N{U+...} in regex; marked by
3044S<<-- HERE> in m/%s/
aec0ef10 3045
8149aa9f 3046(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
3047number. Either it is empty, or you tried to use a character other than
30480 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 3049
6651ba0b
FC
3050=item Invalid module name %s with -%c option: contains single ':'
3051
3052(F) The module argument to perl's B<-m> and B<-M> command-line options
3053cannot contain single colons in the module name, but only in the
3054arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
3055B<-MFoo:Bar=baz> is not.
3056
2c7d6b9c
RGS
3057=item Invalid mro name: '%s'
3058
162a3e34
FC
3059(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
3060where C<foo> is not a valid method resolution order (MRO). Currently,
3061the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
3062a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 3063
40e4140b
FC
3064=item Invalid negative number (%s) in chr
3065
3066(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 3067not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
3068character (U+FFFD).
3069
74d1b2e4
FC
3070=item Invalid number '%s' for -C option.
3071
3072(F) You supplied a number to the -C option that either has extra leading
3073zeroes or overflows perl's unsigned integer representation.
3074
6651ba0b
FC
3075=item invalid option -D%c, use -D'' to see choices
3076
8ff21bfe
FC
3077(S debugging) Perl was called with invalid debugger flags. Call perl
3078with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 3079See also L<perlrun/-Dletters>.
6651ba0b 3080
6e8a73f2 3081=item Invalid quantifier in {,} in regex; marked by S<<-- HERE> in m/%s/
35cd12d1
HS
3082
3083(F) The pattern looks like a {min,max} quantifier, but the min or max
3084could not be parsed as a valid number - either it has leading zeroes,
3085or it represents too big a number to cope with. The S<<-- HERE> shows
3086where in the regular expression the problem was discovered. See L<perlre>.
3087
e0e4a6e3 3088=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
3089
3090(F) The range specified in a character class had a minimum character
7253e4e3
RK
3091greater than the maximum character. One possibility is that you forgot the
3092C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 3093up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 3094problem was discovered. See L<perlre>.
6df41af2 3095
d1573ac7 3096=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
3097
3098(F) The range specified in the tr/// or y/// operator had a minimum
3099character greater than the maximum character. See L<perlop>.
3100
09bef843
SB
3101=item Invalid separator character %s in attribute list
3102
0120eecf 3103(F) Something other than a colon or whitespace was seen between the
be771a83
GS
3104elements of an attribute list. If the previous attribute had a
3105parenthesised parameter list, perhaps that list was terminated too soon.
3106See L<attributes>.
09bef843 3107
b4581f09
JH
3108=item Invalid separator character %s in PerlIO layer specification %s
3109
2bfc5f71
FC
3110(W layer) When pushing layers onto the Perl I/O system, something other
3111than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
3112If the previous attribute had a parenthesised parameter list, perhaps that
3113list was terminated too soon.
3114
2c86d456
DG
3115=item Invalid strict version format (%s)
3116
fa816bf3 3117(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
3118A "strict" version number is a positive decimal number (integer or
3119decimal-fraction) without exponentiation or else a dotted-decimal
3120v-string with a leading 'v' character and at least three components.
a6485a24 3121The parenthesized text indicates which criteria were not met.
2c86d456
DG
3122See the L<version> module for more details on allowed version formats.
3123
49704364 3124=item Invalid type '%s' in %s
96e4d5b1 3125
49704364
LW
3126(F) The given character is not a valid pack or unpack type.
3127See L<perlfunc/pack>.
6728c851 3128
49704364 3129(W) The given character is not a valid pack or unpack type but used to be
75b44862 3130silently ignored.
96e4d5b1 3131
2c86d456
DG
3132=item Invalid version format (%s)
3133
fa816bf3 3134(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
3135A "lax" version number is a positive decimal number (integer or
3136decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
3137v-string. If the v-string has fewer than three components, it
3138must have a leading 'v' character. Otherwise, the leading 'v' is
3139optional. Both decimal and dotted-decimal versions may have a
3140trailing "alpha" component separated by an underscore character
3141after a fractional or dotted-decimal component. The parenthesized
3142text indicates which criteria were not met. See the L<version> module
3143for more details on allowed version formats.
46314c13 3144
798ae1b7
DG
3145=item Invalid version object
3146
fa816bf3
FC
3147(F) The internal structure of the version object was invalid.
3148Perhaps the internals were modified directly in some way or
3149an arbitrary reference was blessed into the "version" class.
798ae1b7 3150
cd209d9d 3151=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 3152marked by S<<-- HERE> in m/%s/
675fa9ff 3153
edf23316
FC
3154(F) The two-character sequence C<"(*"> in this context in a regular
3155expression pattern should be an indivisible token, with nothing
3156intervening between the C<"("> and the C<"*">, but you separated them.
675fa9ff 3157
a0d0e21e
LW
3158=item ioctl is not implemented
3159
3160(F) Your machine apparently doesn't implement ioctl(), which is pretty
3161strange for a machine that supports C.
3162
c289d2f7
JH
3163=item ioctl() on unopened %s
3164
3165(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 3166Check your control flow and number of arguments.
c289d2f7 3167
fe13d51d 3168=item IO layers (like '%s') unavailable
363c40c4
SB
3169
3170(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 3171you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
3172with 'useperlio'.
3173
80cbd5ad
JH
3174=item IO::Socket::atmark not implemented on this architecture
3175
3176(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 3177neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 3178
6e8a73f2 3179=item '%s' is an unknown bound type in regex; marked by S<<-- HERE> in m/%s/
64935bc6
KW
3180
3181(F) You used C<\b{...}> or C<\B{...}> and the C<...> is not known to
3182Perl. The current valid ones are given in
3183L<perlrebackslash/\b{}, \b, \B{}, \B>.
3184
ac3afc4b
YO
3185=item %s is forbidden - matches null string many times in regex; marked by S<<-- HERE> in
3186m/%s/
3187
3188(F) The pattern you've specified might cause the regular expression to
3189infinite loop so it is forbidden. The S<<-- HERE>
3190shows whereabouts in the regular expression the problem was discovered.
3191See L<perlre>.
3192
1ed4b776 3193=item %s() isn't allowed on :utf8 handles
74d1b2e4 3194
1ed4b776
TC
3195(F) The sysread(), recv(), syswrite() and send() operators are
3196not allowed on handles that have the C<:utf8> layer, either explicitly, or
74d1b2e4
FC
3197implicitly, eg., with the C<:encoding(UTF-16LE)> layer.
3198
1ed4b776
TC
3199Previously sysread() and recv() currently use only the C<:utf8> flag for the stream,
3200ignoring the actual layers. Since sysread() and recv() did no UTF-8
74d1b2e4
FC
3201validation they can end up creating invalidly encoded scalars.
3202
1ed4b776
TC
3203Similarly, syswrite() and send() used only the C<:utf8> flag, otherwise ignoring
3204any layers. If the flag is set, both wrote the value UTF-8 encoded, even if
74d1b2e4
FC
3205the layer is some different encoding, such as the example above.
3206
3207Ideally, all of these operators would completely ignore the C<:utf8> state,
3208working only with bytes, but this would result in silently breaking existing
1972ac5c
A
3209code.
3210
d4360efa 3211=item "%s" is more clearly written simply as "%s" in regex; marked by S<<-- HERE> in m/%s/
acdfc3b6 3212
d4360efa 3213(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
30b17cc1 3214
3f673807
FC
3215You specified a character that has the given plainer way of writing it, and
3216which is also portable to platforms running with different character sets.
acdfc3b6 3217
dcb414ac 3218=item $* is no longer supported as of Perl 5.30
a678626e 3219
dcb414ac
JK
3220(F) The special variable C<$*>, deprecated in older perls, was removed in
32215.10.0, is no longer supported and is a fatal error as of Perl 5.30. In
a678626e
A
3222previous versions of perl the use of C<$*> enabled or disabled multi-line
3223matching within a string.
3224
3225Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
3226modifiers. You can enable C</m> for a lexical scope (even a whole file)
3227with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
3228then all regular expressions behaved as if they were written using C</m>.)
3229
37398dc1
A
3230Use of this variable will be a fatal error in Perl 5.30.
3231
dcb414ac 3232=item $# is no longer supported as of Perl 5.30
a678626e 3233
dcb414ac
JK
3234(F) The special variable C<$#>, deprecated in older perls, was removed as of
32355.10.0, is no longer supported and is a fatal error as of Perl 5.30. You
a678626e
A
3236should use the printf/sprintf functions instead.
3237
ccf3535a 3238=item '%s' is not a code reference
6ad11d81 3239
6903afa2
FC
3240(W overload) The second (fourth, sixth, ...) argument of
3241overload::constant needs to be a code reference. Either
3242an anonymous subroutine, or a reference to a subroutine.
6ad11d81 3243
ccf3535a 3244=item '%s' is not an overloadable type
6ad11d81 3245
04a80ee0
RGS
3246(W overload) You tried to overload a constant type the overload package is
3247unaware of.
6ad11d81 3248
813e85a0
PLE
3249=item isa is experimental
3250
3251(S experimental::isa) This warning is emitted if you use the (C<isa>)
3252operator. This operator is currently experimental and its behaviour may
3253change in future releases of Perl.
3254
5a25739d
FC
3255=item -i used with no filenames on the command line, reading from STDIN
3256
3257(S inplace) The C<-i> option was passed on the command line, indicating
3258that the script is intended to edit files in place, but no files were
3259given. This is usually a mistake, since editing STDIN in place doesn't
3260make sense, and can be confusing because it can make perl look like
3261it is hanging when it is really just trying to read from STDIN. You
3262should either pass a filename to edit, or remove C<-i> from the command
028611fa 3263line. See L<perlrun|perlrun/-i[extension]> for more details.
5a25739d 3264
aec0ef10 3265=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
3266
3267(P) The regular expression parser is confused.
3268
105c827d
TC
3269=item \K not permitted in lookahead/lookbehind in regex; marked by <-- HERE in m/%s/
3270
3271(F) Your regular expression used C<\K> in a lookhead or lookbehind
3272assertion, which isn't permitted.
3273
a0d0e21e
LW
3274=item Label not found for "last %s"
3275
be771a83
GS
3276(F) You named a loop to break out of, but you're not currently in a loop
3277of that name, not even if you count where you were called from. See
3278L<perlfunc/last>.
a0d0e21e
LW
3279
3280=item Label not found for "next %s"
3281
3282(F) You named a loop to continue, but you're not currently in a loop of
3283that name, not even if you count where you were called from. See
3284L<perlfunc/last>.
3285
3286=item Label not found for "redo %s"
3287
3288(F) You named a loop to restart, but you're not currently in a loop of
3289that name, not even if you count where you were called from. See
3290L<perlfunc/last>.
3291
85ab1d1d 3292=item leaving effective %s failed
5ff3f7a4 3293
85ab1d1d 3294(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
3295effective uids or gids failed.
3296
49704364
LW
3297=item length/code after end of string in unpack
3298
d7f8936a 3299(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
3300length/code combination tried to obtain more data. This results in
3301an undefined value for the length. See L<perlfunc/pack>.
49704364 3302
25e26107 3303=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 3304
0d46a4e7
FC
3305(W syntax) You used length() on either an array or a hash when you
3306probably wanted a count of the items.
e508c8a4
MH
3307
3308Array size can be obtained by doing:
3309
3310 scalar(@array);
3311
3312The number of items in a hash can be obtained by doing:
3313
3314 scalar(keys %hash);
3315
f0e67a1d
Z
3316=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
3317
d4fe7078
RS
3318(F) An extension is attempting to insert text into the current parse
3319(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
3320couldn't be part of the current input. This is an inherent pitfall
3321of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 3322it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
3323
3324=item Lexing code internal error (%s)
3325
3326(F) Lexing code supplied by an extension violated the lexer's API in a
3327detectable way.
3328
69282e91 3329=item listen() on closed socket %s
a0d0e21e 3330
be771a83
GS
3331(W closed) You tried to do a listen on a closed socket. Did you forget
3332to check the return value of your socket() call? See
3333L<perlfunc/listen>.
a0d0e21e 3334
6651ba0b
FC
3335=item List form of piped open not implemented
3336
3337(F) On some platforms, notably Windows, the three-or-more-arguments
3338form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
3339Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
3340
2a6971a9
KW
3341=item Literal vertical space in [] is illegal except under /x in regex;
3342marked by S<<-- HERE> in m/%s/
3343
3344(F) (only under C<S<use re 'strict'>> or within C<(?[...])>)
3345
3346Likely you forgot the C</x> modifier or there was a typo in the pattern.
3347For example, did you really mean to match a form-feed? If so, all the
3348ASCII vertical space control characters are representable by escape
3349sequences which won't present such a jarring appearance as your pattern
3350does when displayed.
3351
3352 \r carriage return
3353 \f form feed
3354 \n line feed
3355 \cK vertical tab
3356
dc6bb7ba
FC
3357=item %s: loadable library and perl binaries are mismatched (got handshake key %p, needed %p)
3358
3359(P) A dynamic loading library C<.so> or C<.dll> was being loaded into the
3360process that was built against a different build of perl than the
3361said library was compiled against. Reinstalling the XS module will
3362likely fix this error.
3363
8b7358b9 3364=item Locale '%s' contains (at least) the following characters which
f03e1e3a 3365have unexpected meanings: %s The Perl program will use the expected
8b7358b9
KW
3366meanings
3367
3368(W locale) You are using the named UTF-8 locale. UTF-8 locales are
578a6a87
KW
3369expected to have very particular behavior, which most do. This message
3370arises when perl found some departures from the expectations, and is
3371notifying you that the expected behavior overrides these differences.
3372In some cases the differences are caused by the locale definition being
3373defective, but the most common causes of this warning are when there are
3374ambiguities and conflicts in following the Standard, and the locale has
3375chosen an approach that differs from Perl's.
3376
3377One of these is because that, contrary to the claims, Unicode is not
a2d13ee0
FC
3378completely locale insensitive. Turkish and some related languages
3379have two types of C<"I"> characters. One is dotted in both upper- and
578a6a87
KW
3380lowercase, and the other is dotless in both cases. Unicode allows a
3381locale to use either the Turkish rules, or the rules used in all other
<