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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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FC
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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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
a730510a
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.
a0d0e21e
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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
087b5369
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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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PP
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
a0d0e21e
LW
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
7a95317d
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443substitution, but perl found a syntax error in the code to evaluate,
444most likely an unexpected right brace '}'.
445
a0d0e21e
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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.
a0d0e21e
LW
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
GS
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
GS
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
867=item Can't do inplace edit without backup
868
869(F) You're on a system such as MS-DOS that gets confused if you try
870reading from a deleted (but still opened) file. You have to say
871C<-i.bak>, or some such.
872
873=item Can't do inplace edit: %s would not be unique
874
875(S inplace) Your filesystem does not support filenames longer than 14
876characters and Perl was unable to create a unique filename during
877inplace editing with the B<-i> switch. The file was ignored.
878
ab0b796c
KW
879=item Can't do %s("%s") on non-UTF-8 locale; resolved to "%s".
880
881(W locale) You are 1) running under "C<use locale>"; 2) the current
882locale is not a UTF-8 one; 3) you tried to do the designated case-change
883operation on the specified Unicode character; and 4) the result of this
884operation would mix Unicode and locale rules, which likely conflict.
885Mixing of different rule types is forbidden, so the operation was not
886done; instead the result is the indicated value, which is the best
887available that uses entirely Unicode rules. That turns out to almost
888always be the original character, unchanged.
889
890It is generally a bad idea to mix non-UTF-8 locales and Unicode, and
891this issue is one of the reasons why. This warning is raised when
892Unicode rules would normally cause the result of this operation to
893contain a character that is in the range specified by the locale,
8940..255, and hence is subject to the locale's rules, not Unicode's.
895
896If you are using locale purely for its characteristics related to things
897like its numeric and time formatting (and not C<LC_CTYPE>), consider
898using a restricted form of the locale pragma (see L<perllocale/The "use
899locale" pragma>) like "S<C<use locale ':not_characters'>>".
900
901Note that failed case-changing operations done as a result of
902case-insensitive C</i> regular expression matching will show up in this
903warning as having the C<fc> operation (as that is what the regular
904expression engine calls behind the scenes.)
905
a0d0e21e
LW
906=item Can't do waitpid with flags
907
be771a83
GS
908(F) This machine doesn't have either waitpid() or wait4(), so only
909waitpid() without flags is emulated.
a0d0e21e 910
a0d0e21e
LW
911=item Can't emulate -%s on #! line
912
be771a83
GS
913(F) The #! line specifies a switch that doesn't make sense at this
914point. For example, it'd be kind of silly to put a B<-x> on the #!
915line.
a0d0e21e 916
1109a392
MHM
917=item Can't %s %s-endian %ss on this platform
918
919(F) Your platform's byte-order is neither big-endian nor little-endian,
920or it has a very strange pointer size. Packing and unpacking big- or
921little-endian floating point values and pointers may not be possible.
922See L<perlfunc/pack>.
923
a0d0e21e
LW
924=item Can't exec "%s": %s
925
d1be9408 926(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
927named program for the indicated reason. Typical reasons include: the
928permissions were wrong on the file, the file wasn't found in
929C<$ENV{PATH}>, the executable in question was compiled for another
930architecture, or the #! line in a script points to an interpreter that
931can't be run for similar reasons. (Or maybe your system doesn't support
932#! at all.)
a0d0e21e
LW
933
934=item Can't exec %s
935
be771a83
GS
936(F) Perl was trying to execute the indicated program for you because
937that's what the #! line said. If that's not what you wanted, you may
938need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
939
940=item Can't execute %s
941
be771a83
GS
942(F) You used the B<-S> switch, but the copies of the script to execute
943found in the PATH did not have correct permissions.
2a92aaa0 944
6df41af2 945=item Can't find an opnumber for "%s"
2a92aaa0 946
be771a83
GS
947(F) A string of a form C<CORE::word> was given to prototype(), but there
948is no builtin with the name C<word>.
6df41af2
GS
949
950=item Can't find label %s
951
be771a83
GS
952(F) You said to goto a label that isn't mentioned anywhere that it's
953possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
954
955=item Can't find %s on PATH
956
be771a83
GS
957(F) You used the B<-S> switch, but the script to execute could not be
958found in the PATH.
a0d0e21e 959
6df41af2 960=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 961
be771a83
GS
962(F) You used the B<-S> switch, but the script to execute could not be
963found in the PATH, or at least not with the correct permissions. The
964script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
965
966=item Can't find string terminator %s anywhere before EOF
967
be771a83
GS
968(F) Perl strings can stretch over multiple lines. This message means
969that the closing delimiter was omitted. Because bracketed quotes count
970nesting levels, the following is missing its final parenthesis:
a0d0e21e 971
fb73857a
PP
972 print q(The character '(' starts a side comment.);
973
97b3d10f 974If you're getting this error from a here-document, you may have
b6b8cb97
FC
975included unseen whitespace before or after your closing tag or there
976may not be a linebreak after it. A good programmer's editor will have
977a way to help you find these characters (or lack of characters). See
978L<perlop> for the full details on here-documents.
a0d0e21e 979
660a4616
ST
980=item Can't find Unicode property definition "%s"
981
29f52644
KW
982=item Can't find Unicode property definition "%s" in regex; marked by <-- HERE in m/%s/
983
984(F) The named property which you specified via C<\p> or C<\P> is not one
985known to Perl. Perhaps you misspelled the name? See
e1b711da 986L<perluniprops/Properties accessible through \p{} and \P{}>
29f52644
KW
987for a complete list of available official
988properties. If it is a
989L<user-defined property|perlunicode/User-Defined Character Properties>
990it must have been defined by the time the regular expression is
991matched.
992
993If you didn't mean to use a Unicode property, escape the C<\p>, either
994by C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 995until C<\E>).
660a4616 996
b3647a36 997=item Can't fork: %s
a0d0e21e 998
be771a83
GS
999(F) A fatal error occurred while trying to fork while opening a
1000pipeline.
a0d0e21e 1001
b3647a36
SR
1002=item Can't fork, trying again in 5 seconds
1003
c973c02e 1004(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
1005after five seconds.
1006
748a9306
LW
1007=item Can't get filespec - stale stat buffer?
1008
be771a83
GS
1009(S) A warning peculiar to VMS. This arises because of the difference
1010between access checks under VMS and under the Unix model Perl assumes.
1011Under VMS, access checks are done by filename, rather than by bits in
1012the stat buffer, so that ACLs and other protections can be taken into
1013account. Unfortunately, Perl assumes that the stat buffer contains all
1014the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 1015the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
1016the device name and FID present in the stat buffer, but this works only
1017if you haven't made a subsequent call to the CRTL stat() routine,
1018because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
1019appears, the name lookup failed, and the access-checking routine gave up
1020and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
1021routine knows about the Perl C<stat> operator and file tests, so you
1022shouldn't ever see this warning in response to a Perl command; it arises
1023only if some internal code takes stat buffers lightly.)
748a9306 1024
a0d0e21e
LW
1025=item Can't get pipe mailbox device name
1026
be771a83
GS
1027(P) An error peculiar to VMS. After creating a mailbox to act as a
1028pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
1029
1030=item Can't get SYSGEN parameter value for MAXBUF
1031
748a9306
LW
1032(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
1033mailbox buffers to be, and didn't get an answer.
a0d0e21e 1034
6d90e983
FC
1035=item Can't "goto" into a binary or list expression
1036
1037(F) A "goto" statement was executed to jump into the middle of a binary
1038or list expression. You can't get there from here. The reason for this
1039restriction is that the interpreter would get confused as to how many
1040arguments there are, resulting in stack corruption or crashes. This
1041error occurs in cases such as these:
1042
1043 goto F;
1044 print do { F: }; # Can't jump into the arguments to print
1045
1046 goto G;
1047 $x + do { G: $y }; # How is + supposed to get its first operand?
1048
a01f4640
FC
1049=item Can't "goto" into a "given" block
1050
1051(F) A "goto" statement was executed to jump into the middle of a C<given>
1052block. You can't get there from here. See L<perlfunc/goto>.
1053
6df41af2 1054=item Can't "goto" into the middle of a foreach loop
a0d0e21e 1055
be771a83
GS
1056(F) A "goto" statement was executed to jump into the middle of a foreach
1057loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
1058
1059=item Can't "goto" out of a pseudo block
1060
be771a83
GS
1061(F) A "goto" statement was executed to jump out of what might look like
1062a block, except that it isn't a proper block. This usually occurs if
1063you tried to jump out of a sort() block or subroutine, which is a no-no.
1064See L<perlfunc/goto>.
a0d0e21e 1065
5a25739d
FC
1066=item Can't goto subroutine from an eval-%s
1067
1068(F) The "goto subroutine" call can't be used to jump out of an eval
1069"string" or block.
1070
9850bf21 1071=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 1072
9850bf21
RH
1073(F) The "goto subroutine" call can't be used to jump out of the
1074comparison sub for a sort(), or from a similar callback (such
1075as the reduce() function in List::Util).
1076
6df41af2
GS
1077=item Can't goto subroutine outside a subroutine
1078
be771a83
GS
1079(F) The deeply magical "goto subroutine" call can only replace one
1080subroutine call for another. It can't manufacture one out of whole
1081cloth. In general you should be calling it out of only an AUTOLOAD
1082routine anyway. See L<perlfunc/goto>.
6df41af2 1083
0b5b802d
GS
1084=item Can't ignore signal CHLD, forcing to default
1085
be771a83
GS
1086(W signal) Perl has detected that it is being run with the SIGCHLD
1087signal (sometimes known as SIGCLD) disabled. Since disabling this
1088signal will interfere with proper determination of exit status of child
1089processes, Perl has reset the signal to its default value. This
1090situation typically indicates that the parent program under which Perl
1091may be running (e.g. cron) is being very careless.
0b5b802d 1092
e2c0f81f
DG
1093=item Can't kill a non-numeric process ID
1094
1095(F) Process identifiers must be (signed) integers. It is a fatal error to
1096attempt to kill() an undefined, empty-string or otherwise non-numeric
1097process identifier.
1098
6df41af2 1099=item Can't "last" outside a loop block
4633a7c4 1100
6df41af2 1101(F) A "last" statement was executed to break out of the current block,
be771a83
GS
1102except that there's this itty bitty problem called there isn't a current
1103block. Note that an "if" or "else" block doesn't count as a "loopish"
1104block, as doesn't a block given to sort(), map() or grep(). You can
1105usually double the curlies to get the same effect though, because the
1106inner curlies will be considered a block that loops once. See
1107L<perlfunc/last>.
4633a7c4 1108
2c7d6b9c
RGS
1109=item Can't linearize anonymous symbol table
1110
1111(F) Perl tried to calculate the method resolution order (MRO) of a
1112package, but failed because the package stash has no name.
1113
b8170e59
JB
1114=item Can't load '%s' for module %s
1115
6903afa2
FC
1116(F) The module you tried to load failed to load a dynamic extension.
1117This may either mean that you upgraded your version of perl to one
1118that is incompatible with your old dynamic extensions (which is known
1119to happen between major versions of perl), or (more likely) that your
1120dynamic extension was built against an older version of the library
1121that is installed on your system. You may need to rebuild your old
1122dynamic extensions.
b8170e59 1123
748a9306
LW
1124=item Can't localize lexical variable %s
1125
2ba9eb46 1126(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
1127lexical variable using "my" or "state". This is not allowed. If you
1128want to localize a package variable of the same name, qualify it with
1129the package name.
748a9306 1130
6df41af2 1131=item Can't localize through a reference
4727527e 1132
6df41af2
GS
1133(F) You said something like C<local $$ref>, which Perl can't currently
1134handle, because when it goes to restore the old value of whatever $ref
be771a83 1135pointed to after the scope of the local() is finished, it can't be sure
64977eb6 1136that $ref will still be a reference.
4727527e 1137
ea071790 1138=item Can't locate %s
ec889f3a 1139
fa816bf3
FC
1140(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
1141Perl looks for the file in all the locations mentioned in @INC, unless
1142the file name included the full path to the file. Perhaps you need
1143to set the PERL5LIB or PERL5OPT environment variable to say where the
1144extra library is, or maybe the script needs to add the library name
be771a83
GS
1145to @INC. Or maybe you just misspelled the name of the file. See
1146L<perlfunc/require> and L<lib>.
a0d0e21e 1147
6df41af2
GS
1148=item Can't locate auto/%s.al in @INC
1149
be771a83
GS
1150(F) A function (or method) was called in a package which allows
1151autoload, but there is no function to autoload. Most probable causes
1152are a misprint in a function/method name or a failure to C<AutoSplit>
1153the file, say, by doing C<make install>.
6df41af2 1154
b8170e59
JB
1155=item Can't locate loadable object for module %s in @INC
1156
1157(F) The module you loaded is trying to load an external library, like
d70d8e57 1158for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1159unable to locate this library. See L<DynaLoader>.
1160
a0d0e21e
LW
1161=item Can't locate object method "%s" via package "%s"
1162
1163(F) You called a method correctly, and it correctly indicated a package
1164functioning as a class, but that package doesn't define that particular
2ba9eb46 1165method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1166
8af56b9d
FC
1167=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1168to load "%s"?)
1169
1170(F) You called a method on a class that did not exist, and the method
1171could not be found in UNIVERSAL. This often means that a method
1172requires a package that has not been loaded.
1173
a0d0e21e
LW
1174=item Can't locate package %s for @%s::ISA
1175
be771a83
GS
1176(W syntax) The @ISA array contained the name of another package that
1177doesn't seem to exist.
a0d0e21e 1178
2f7da168
RK
1179=item Can't locate PerlIO%s
1180
1181(F) You tried to use in open() a PerlIO layer that does not exist,
1182e.g. open(FH, ">:nosuchlayer", "somefile").
1183
f4ad53f4 1184=item Can't make list assignment to %ENV on this system
3e3baf6d 1185
be771a83
GS
1186(F) List assignment to %ENV is not supported on some systems, notably
1187VMS.
3e3baf6d 1188
cd40cd58
NC
1189=item Can't make loaded symbols global on this platform while loading %s
1190
ff9c1ae8 1191(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1192that symbols from the stated file are made available globally within the
1193process, but that functionality is not available on this platform. Whilst
1194the module likely will still work, this may prevent the perl interpreter
1195from loading other XS-based extensions which need to link directly to
1196functions defined in the C or XS code in the stated file.
1197
a0d0e21e
LW
1198=item Can't modify %s in %s
1199
be771a83
GS
1200(F) You aren't allowed to assign to the item indicated, or otherwise try
1201to change it, such as with an auto-increment.
a0d0e21e 1202
54310121 1203=item Can't modify nonexistent substring
a0d0e21e
LW
1204
1205(P) The internal routine that does assignment to a substr() was handed
1206a NULL.
1207
0f948285 1208=item Can't modify non-lvalue subroutine call of &%s
6df41af2 1209
8d9d0498
FC
1210=item Can't modify non-lvalue subroutine call of &%s in %s
1211
6df41af2 1212(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1213such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1214
cf6e1fa1
FC
1215=item Can't modify reference to %s in %s assignment
1216
1217(F) Only a limited number of constructs can be used as the argument to a
1218reference constructor on the left-hand side of an assignment, and what
1219you used was not one of them. See L<perlref/Assigning to References>.
1220
1221=item Can't modify reference to localized parenthesized array in list
1222assignment
1223
1224(F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1225it is not clear exactly what it should do. If you meant to make @array
1226refer to some other array, use C<\@array = \@other_array>. If you want to
1227make the elements of @array aliases of the scalars referenced on the
1228right-hand side, use C<\(@array) = @scalar_refs>.
1229
1230=item Can't modify reference to parenthesized hash in list assignment
1231
1232(F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1233refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1234make the elements of %hash into aliases of the scalars referenced on the
1235right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1236
5f05dabc 1237=item Can't msgrcv to read-only var
a0d0e21e 1238
5f05dabc 1239(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1240buffer.
1241
6df41af2
GS
1242=item Can't "next" outside a loop block
1243
1244(F) A "next" statement was executed to reiterate the current block, but
1245there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1246count as a "loopish" block, as doesn't a block given to sort(), map() or
1247grep(). You can usually double the curlies to get the same effect
1248though, because the inner curlies will be considered a block that loops
1249once. See L<perlfunc/next>.
6df41af2 1250
a0d0e21e
LW
1251=item Can't open %s: %s
1252
c47ff5f1 1253(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1254filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1255switches, or explicitly, failed for the indicated reason. Usually
1256this is because you don't have read permission for a file which
1257you named on the command line.
1258
1259(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1260your operating system's equivalent) could not be opened.
a0d0e21e 1261
9a869a14
RGS
1262=item Can't open a reference
1263
1264(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1265using the 3-arg open() syntax:
9a869a14
RGS
1266
1267 open FH, '>', $ref;
1268
1269but your version of perl is compiled without perlio, and this form of
1270open is not supported.
1271
a0d0e21e
LW
1272=item Can't open bidirectional pipe
1273
be771a83
GS
1274(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1275You can try any of several modules in the Perl library to do this, such
1276as IPC::Open2. Alternately, direct the pipe's output to a file using
1277">", and then read it in under a different file handle.
a0d0e21e 1278
748a9306
LW
1279=item Can't open error file %s as stderr
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 '2>' or '2>>' on
1283the command line for writing.
748a9306
LW
1284
1285=item Can't open input file %s as stdin
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 '<' on the
1289command line for reading.
748a9306
LW
1290
1291=item Can't open output file %s as stdout
1292
be771a83
GS
1293(F) An error peculiar to VMS. Perl does its own command line
1294redirection, and couldn't open the file specified after '>' or '>>' on
1295the command line for writing.
748a9306
LW
1296
1297=item Can't open output pipe (name: %s)
1298
be771a83
GS
1299(P) An error peculiar to VMS. Perl does its own command line
1300redirection, and couldn't open the pipe into which to send data destined
1301for stdout.
748a9306 1302
3b1cf97d 1303=item Can't open perl script "%s": %s
a0d0e21e
LW
1304
1305(F) The script you specified can't be opened for the indicated reason.
1306
fa3aa65a
JC
1307If you're debugging a script that uses #!, and normally relies on the
1308shell's $PATH search, the -S option causes perl to do that search, so
1309you don't have to type the path or C<`which $scriptname`>.
1310
6df41af2
GS
1311=item Can't read CRTL environ
1312
1313(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1314from the CRTL's internal environment array and discovered the array was
1315missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1316or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1317searched.
6df41af2 1318
f3106bc8
LM
1319=item Can't redeclare "%s" in "%s"
1320
1321(F) A "my", "our" or "state" declaration was found within another declaration,
1322such as C<my ($x, my($y), $z)> or C<our (my $x)>.
1323
6df41af2
GS
1324=item Can't "redo" outside a loop block
1325
1326(F) A "redo" statement was executed to restart the current block, but
1327there isn't a current block. Note that an "if" or "else" block doesn't
1328count as a "loopish" block, as doesn't a block given to sort(), map()
1329or grep(). You can usually double the curlies to get the same effect
1330though, because the inner curlies will be considered a block that
1331loops once. See L<perlfunc/redo>.
1332
64977eb6 1333=item Can't remove %s: %s, skipping file
10f9c03d 1334
be771a83
GS
1335(S inplace) You requested an inplace edit without creating a backup
1336file. Perl was unable to remove the original file to replace it with
1337the modified file. The file was left unmodified.
10f9c03d 1338
e0d4aead
TC
1339=item Can't rename in-place work file '%s' to '%s': %s
1340
1341(F) When closed implicitly, the temporary file for in-place editing
1342couldn't be renamed to the original filename.
1343
ecc6274e
FC
1344=item Can't rename %s to %s: %s, skipping file
1345
1346(F) The rename done by the B<-i> switch failed for some reason,
1347probably because you don't have write permission to the directory.
1348
748a9306
LW
1349=item Can't reopen input pipe (name: %s) in binary mode
1350
be771a83
GS
1351(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1352to reopen it to accept binary data. Alas, it failed.
748a9306 1353
9415f659
KW
1354=item Can't represent character for Ox%X on this platform
1355
1356(F) There is a hard limit to how big a character code point can be due
1357to the fundamental properties of UTF-8, especially on EBCDIC
1358platforms. The given code point exceeds that. The only work-around is
1359to not use such a large code point.
1360
4f12ec0e
FC
1361=item Can't reset %ENV on this system
1362
1363(F) You called C<reset('E')> or similar, which tried to reset
1364all variables in the current package beginning with "E". In
1365the main package, that includes %ENV. Resetting %ENV is not
1366supported on some systems, notably VMS.
1367
fe13d51d 1368=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1369
1fa582fa
FC
1370(F)(P) Error resolving overloading specified by a method name (as
1371opposed to a subroutine reference): no such method callable via the
1372package. If the method name is C<???>, this is an internal error.
6df41af2 1373
cd06dffe
GS
1374=item Can't return %s from lvalue subroutine
1375
be771a83
GS
1376(F) Perl detected an attempt to return illegal lvalues (such as
1377temporary or readonly values) from a subroutine used as an lvalue. This
1378is not allowed.
cd06dffe 1379
96ebfdd7
RK
1380=item Can't return outside a subroutine
1381
1382(F) The return statement was executed in mainline code, that is, where
1383there was no subroutine call to return out of. See L<perlsub>.
1384
78f9721b
SM
1385=item Can't return %s to lvalue scalar context
1386
6903afa2
FC
1387(F) You tried to return a complete array or hash from an lvalue
1388subroutine, but you called the subroutine in a way that made Perl
1389think you meant to return only one value. You probably meant to
1390write parentheses around the call to the subroutine, which tell
1391Perl that the call should be in list context.
78f9721b 1392
a0d0e21e
LW
1393=item Can't stat script "%s"
1394
be771a83
GS
1395(P) For some reason you can't fstat() the script even though you have it
1396open already. Bizarre.
a0d0e21e 1397
a0d0e21e
LW
1398=item Can't take log of %g
1399
fb73857a 1400(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1401negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1402standard with Perl, though, if you really want to do that for the
1403negative numbers.
a0d0e21e
LW
1404
1405=item Can't take sqrt of %g
1406
1407(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1408negative number. There's a Math::Complex package that comes standard
1409with Perl, though, if you really want to do that.
a0d0e21e
LW
1410
1411=item Can't undef active subroutine
1412
1413(F) You can't undefine a routine that's currently running. You can,
1414however, redefine it while it's running, and you can even undef the
1415redefined subroutine while the old routine is running. Go figure.
1416
ecc6274e
FC
1417=item Can't unweaken a nonreference
1418
1419(F) You attempted to unweaken something that was not a reference. Only
1420references can be unweakened.
1421
c81225bc 1422=item Can't upgrade %s (%d) to %d
a0d0e21e 1423
be771a83
GS
1424(P) The internal sv_upgrade routine adds "members" to an SV, making it
1425into a more specialized kind of SV. The top several SV types are so
1426specialized, however, that they cannot be interconverted. This message
1427indicates that such a conversion was attempted.
a0d0e21e 1428
6651ba0b
FC
1429=item Can't use '%c' after -mname
1430
1431(F) You tried to call perl with the B<-m> switch, but you put something
1432other than "=" after the module name.
1433
1f1ec7b5
KW
1434=item Can't use a hash as a reference
1435
1436(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1437C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1438<= 5.22.0 used to allow this syntax, but shouldn't
1439have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1440
1441=item Can't use an array as a reference
1442
1443(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1444C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1445used to allow this syntax, but shouldn't have. This
1446was deprecated in perl 5.6.1.
1f1ec7b5 1447
1db89ea5
BS
1448=item Can't use anonymous symbol table for method lookup
1449
e27ad1f2 1450(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1451table that doesn't have a name. Symbol tables can become anonymous
1452for example by undefining stashes: C<undef %Some::Package::>.
1453
96ebfdd7
RK
1454=item Can't use an undefined value as %s reference
1455
1456(F) A value used as either a hard reference or a symbolic reference must
1457be a defined value. This helps to delurk some insidious errors.
1458
6df41af2
GS
1459=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1460
be771a83
GS
1461(F) Only hard references are allowed by "strict refs". Symbolic
1462references are disallowed. See L<perlref>.
6df41af2 1463
90b75b61 1464=item Can't use %! because Errno.pm is not available
1d2dff63 1465
20561843 1466(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1467Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1468provide symbolic names for C<$!> errno values.
1469
1109a392
MHM
1470=item Can't use both '<' and '>' after type '%c' in %s
1471
1472(F) A type cannot be forced to have both big-endian and little-endian
1473byte-order at the same time, so this combination of modifiers is not
1474allowed. See L<perlfunc/pack>.
1475
e35475de
KW
1476=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1477
1478(F) defined() is not useful on arrays because it
1479checks for an undefined I<scalar> value. If you want to see if the
1480array is empty, just use C<if (@array) { # not empty }> for example.
1481
1482=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1483
1484(F) C<defined()> is not usually right on hashes.
1485
1486Although C<defined %hash> is false on a plain not-yet-used hash, it
1487becomes true in several non-obvious circumstances, including iterators,
1488weak references, stash names, even remaining true after C<undef %hash>.
1489These things make C<defined %hash> fairly useless in practice, so it now
1490generates a fatal error.
1491
1492If a check for non-empty is what you wanted then just put it in boolean
1493context (see L<perldata/Scalar values>):
1494
1495 if (%hash) {
1496 # not empty
1497 }
1498
1499If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1500variable exists then that's never really been reliable, and isn't
1501a good way to enquire about the features of a package, or whether
1502it's loaded, etc.
1503
6df41af2
GS
1504=item Can't use %s for loop variable
1505
c1f06047 1506(P) The parser got confused when trying to parse a C<foreach> loop.
6df41af2 1507
aab6a793 1508=item Can't use global %s in "%s"
6df41af2 1509
be771a83
GS
1510(F) You tried to declare a magical variable as a lexical variable. This
1511is not allowed, because the magic can be tied to only one location
1512(namely the global variable) and it would be incredibly confusing to
1513have variables in your program that looked like magical variables but
6df41af2
GS
1514weren't.
1515
6d3b25aa
RGS
1516=item Can't use '%c' in a group with different byte-order in %s
1517
1518(F) You attempted to force a different byte-order on a type
1519that is already inside a group with a byte-order modifier.
1520For example you cannot force little-endianness on a type that
1521is inside a big-endian group.
1522
c07a80fd
PP
1523=item Can't use "my %s" in sort comparison
1524
1525(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1526You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1527and the variable had earlier been declared as a lexical variable.
1528Either qualify the sort variable with the package name, or rename the
1529lexical variable.
1530
a0d0e21e
LW
1531=item Can't use %s ref as %s ref
1532
1533(F) You've mixed up your reference types. You have to dereference a
1534reference of the type needed. You can use the ref() function to
1535test the type of the reference, if need be.
1536
748a9306 1537=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1538
5e634d20
FC
1539=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1540
b41bf23f
FC
1541(F) You've told Perl to dereference a string, something which
1542C<use strict> blocks to prevent it happening accidentally. See
1543L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1544in a double-quoted string immediately before interpolating a variable,
1545for example in C<"user @$twitter_id">, which says to treat the contents
1546of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1547symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1548
748a9306
LW
1549=item Can't use subscript on %s
1550
1551(F) The compiler tried to interpret a bracketed expression as a
1552subscript. But to the left of the brackets was an expression that
209e7cf1 1553didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1554
6df41af2
GS
1555=item Can't use \%c to mean $%c in expression
1556
75b44862
GS
1557(W syntax) In an ordinary expression, backslash is a unary operator that
1558creates a reference to its argument. The use of backslash to indicate a
1559backreference to a matched substring is valid only as part of a regular
be771a83
GS
1560expression pattern. Trying to do this in ordinary Perl code produces a
1561value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1562instead.
6df41af2 1563
810b8aa5
GS
1564=item Can't weaken a nonreference
1565
1566(F) You attempted to weaken something that was not a reference. Only
1567references can be weakened.
1568
7896dde7
Z
1569=item Can't "when" outside a topicalizer
1570
1571(F) You have used a when() block that is neither inside a C<foreach>
1572loop nor a C<given> block. (Note that this error is issued on exit
1573from the C<when> block, so you won't get the error if the match fails,
1574or if you use an explicit C<continue>.)
1575
5f05dabc 1576=item Can't x= to read-only value
a0d0e21e 1577
be771a83
GS
1578(F) You tried to repeat a constant value (often the undefined value)
1579with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1580Perhaps you need to copy the value to a temporary, and repeat that.
1581
a04e6aad 1582=item Character following "\c" must be printable ASCII
f9d13529 1583
7357bd17 1584(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1585
727b6379 1586Note that ASCII characters that don't map to control characters are
7357bd17 1587discouraged, and will generate the warning (when enabled)
d4360efa 1588L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1589
163a633c
KW
1590=item Character following \%c must be '{' or a single-character Unicode property name in regex; marked by <-- HERE in m/%s/
1591
1592(F) (In the above the C<%c> is replaced by either C<p> or C<P>.) You
1593specified something that isn't a legal Unicode property name. Most
1594Unicode properties are specified by C<\p{...}>. But if the name is a
1595single character one, the braces may be omitted.
1596
f337b084 1597=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1598
1599(W pack) You said
1600
1601 pack("C", $x)
1602
1603where $x is either less than 0 or more than 255; the C<"C"> format is
1604only for encoding native operating system characters (ASCII, EBCDIC,
1605and so on) and not for Unicode characters, so Perl behaved as if you meant
1606
1607 pack("C", $x & 255)
1608
1609If you actually want to pack Unicode codepoints, use the C<"U"> format
1610instead.
1611
f337b084 1612=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1613
1614(W pack) You said
1615
1616 pack("c", $x)
1617
1618where $x is either less than -128 or more than 127; the C<"c"> format
1619is only for encoding native operating system characters (ASCII, EBCDIC,
1620and so on) and not for Unicode characters, so Perl behaved as if you meant
1621
1622 pack("c", $x & 255);
1623
1624If you actually want to pack Unicode codepoints, use the C<"U"> format
1625instead.
1626
f337b084
TH
1627=item Character in '%c' format wrapped in unpack
1628
1629(W unpack) You tried something like
1630
1631 unpack("H", "\x{2a1}")
1632
1a147d38 1633where the format expects to process a byte (a character with a value
6903afa2
FC
1634below 256), but a higher value was provided instead. Perl uses the
1635value modulus 256 instead, as if you had provided:
f337b084
TH
1636
1637 unpack("H", "\x{a1}")
1638
5a25739d
FC
1639=item Character in 'W' format wrapped in pack
1640
1641(W pack) You said
1642
1643 pack("U0W", $x)
1644
1645where $x is either less than 0 or more than 255. However, C<U0>-mode
1646expects all values to fall in the interval [0, 255], so Perl behaved
1647as if you meant:
1648
1649 pack("U0W", $x & 255)
1650
f337b084
TH
1651=item Character(s) in '%c' format wrapped in pack
1652
1653(W pack) You tried something like
1654
1655 pack("u", "\x{1f3}b")
1656
1a147d38 1657where the format expects to process a sequence of bytes (character with a
6903afa2 1658value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1659uses the character values modulus 256 instead, as if you had provided:
1660
1661 pack("u", "\x{f3}b")
1662
1663=item Character(s) in '%c' format wrapped in unpack
1664
1665(W unpack) You tried something like
1666
1667 unpack("s", "\x{1f3}b")
1668
1a147d38 1669where the format expects to process a sequence of bytes (character with a
6903afa2 1670value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1671uses the character values modulus 256 instead, as if you had provided:
1672
1673 unpack("s", "\x{f3}b")
1674
8d9d0498
FC
1675=item charnames alias definitions may not contain a sequence of multiple
1676spaces; marked by S<<-- HERE> in %s
f51551f7
FC
1677
1678(F) You defined a character name which had multiple space characters
1679in a row. Change them to single spaces. Usually these names are
1680defined in the C<:alias> import argument to C<use charnames>, but they
1681could be defined by a translator installed into C<$^H{charnames}>. See
1682L<charnames/CUSTOM ALIASES>.
1683
8d9d0498
FC
1684=item charnames alias definitions may not contain trailing white-space;
1685marked by S<<-- HERE> in %s
f51551f7
FC
1686
1687(F) You defined a character name which ended in a space
1688character. Remove the trailing space(s). Usually these names are
1689defined in the C<:alias> import argument to C<use charnames>, but they
1690could be defined by a translator installed into C<$^H{charnames}>.
1691See L<charnames/CUSTOM ALIASES>.
1692
60121127
TC
1693=item chdir() on unopened filehandle %s
1694
1695(W unopened) You tried chdir() on a filehandle that was never opened.
1696
d4360efa 1697=item "\c%c" is more clearly written simply as "%s"
f866a7cd 1698
d4360efa
S
1699(W syntax) The C<\cI<X>> construct is intended to be a way to specify
1700non-printable characters. You used it for a printable one, which
1701is better written as simply itself, perhaps preceded by a backslash
1702for non-word characters. Doing it the way you did is not portable
1703between ASCII and EBCDIC platforms.
f866a7cd 1704
6651ba0b
FC
1705=item Cloning substitution context is unimplemented
1706
1707(F) Creating a new thread inside the C<s///> operator is not supported.
1708
abc7ecad
SP
1709=item closedir() attempted on invalid dirhandle %s
1710
1711(W io) The dirhandle you tried to close is either closed or not really
1712a dirhandle. Check your control flow.
1713
5a25739d
FC
1714=item close() on unopened filehandle %s
1715
1716(W unopened) You tried to close a filehandle that was never opened.
1717
541ed3a9
FC
1718=item Closure prototype called
1719
1720(F) If a closure has attributes, the subroutine passed to an attribute
1721handler is the prototype that is cloned when a new closure is created.
1722This subroutine cannot be called.
1723
74d1b2e4
FC
1724=item \C no longer supported in regex; marked by S<<-- HERE> in m/%s/
1725
1726(F) The \C character class used to allow a match of single byte
1727within a multi-byte utf-8 character, but was removed in v5.24 as
1728it broke encapsulation and its implementation was extremely buggy.
1729If you really need to process the individual bytes, you probably
1730want to convert your string to one where each underlying byte is
1731stored as a character, with utf8::encode().
1732
49704364
LW
1733=item Code missing after '/'
1734
6903afa2
FC
1735(F) You had a (sub-)template that ends with a '/'. There must be
1736another template code following the slash. See L<perlfunc/pack>.
49704364 1737
c0236afe
KW
1738=item Code point 0x%X is not Unicode, and not portable
1739
1740(S non_unicode) You had a code point that has never been in any
1741standard, so it is likely that languages other than Perl will NOT
1742understand it. At one time, it was legal in some standards to have code
1743points up to 0x7FFF_FFFF, but not higher, and this code point is higher.
1744
1745Acceptance of these code points is a Perl extension, and you should
1746expect that nothing other than Perl can handle them; Perl itself on
1747EBCDIC platforms before v5.24 does not handle them.
1748
1749Code points above 0xFFFF_FFFF require larger than a 32 bit word.
1750
1751Perl also makes no guarantees that the representation of these code
1752points won't change at some point in the future, say when machines
1753become available that have larger than a 64-bit word. At that time,
1754files written by an older Perl would require conversion before being
1755readable by a newer Perl.
1756
5a25739d
FC
1757=item Code point 0x%X is not Unicode, may not be portable
1758
2d88a86a 1759(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1760of U+10FFFF.
1761
c0236afe
KW
1762Perl allows strings to contain a superset of Unicode code points, but
1763these may not be accepted by other languages/systems. Further, even if
1764these languages/systems accept these large code points, they may have
1765chosen a different representation for them than the UTF-8-like one that
1766Perl has, which would mean files are not exchangeable between them and
1767Perl.
1768
1769On EBCDIC platforms, code points above 0x3FFF_FFFF have a different
1770representation in Perl v5.24 than before, so any file containing these
1771that was written before that version will require conversion before
1772being readable by a later Perl.
0876b9a0 1773
6df41af2
GS
1774=item %s: Command not found
1775
a892b81a 1776(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1777instead of Perl. Check the #! line, or manually feed your script into
1778Perl yourself. The #! line at the top of your file could look like
8f721816 1779
3bcfc7b3
LM
1780 #!/usr/bin/perl
1781
1782=item %s: command not found
1783
1784(A) You've accidentally run your script through B<bash> or another shell
1785instead of Perl. Check the #! line, or manually feed your script into
1786Perl yourself. The #! line at the top of your file could look like
1787
1788 #!/usr/bin/perl
1789
1790=item %s: command not found: %s
1791
1792(A) You've accidentally run your script through B<zsh> or another shell
1793instead of Perl. Check the #! line, or manually feed your script into
1794Perl yourself. The #! line at the top of your file could look like
1795
1796 #!/usr/bin/perl
6df41af2 1797
7a2e2cd6
PP
1798=item Compilation failed in require
1799
1800(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1801Perl uses this generic message when none of the errors that it
1802encountered were severe enough to halt compilation immediately.
7a2e2cd6 1803
c3464db5
DD
1804=item Complex regular subexpression recursion limit (%d) exceeded
1805
be771a83
GS
1806(W regexp) The regular expression engine uses recursion in complex
1807situations where back-tracking is required. Recursion depth is limited
1808to 32766, or perhaps less in architectures where the stack cannot grow
1809arbitrarily. ("Simple" and "medium" situations are handled without
1810recursion and are not subject to a limit.) Try shortening the string
1811under examination; looping in Perl code (e.g. with C<while>) rather than
1812in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1813that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1814on I<Mastering Regular Expressions>.)
c3464db5 1815
69282e91 1816=item connect() on closed socket %s
a0d0e21e 1817
be771a83
GS
1818(W closed) You tried to do a connect on a closed socket. Did you forget
1819to check the return value of your socket() call? See
1820L<perlfunc/connect>.
a0d0e21e 1821
e21e7c6a
FC
1822=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1823
1824(F) The subroutine registered to handle constant overloading
1825(see L<overload>) or a custom charnames handler (see
1826L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1827
1828=item Constant(%s): $^H{%s} is not defined
1829
1830(F) The parser found inconsistencies while attempting to define an
1831overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1832L<overload> pragma?
e21e7c6a 1833
779c5bc9
GS
1834=item Constant is not %s reference
1835
1836(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1837is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1838The message indicates the type of reference that was expected. This
be771a83 1839usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1840See L<perlsub/"Constant Functions"> and L<constant>.
1841
0ac016fc 1842=item Constants from lexical variables potentially modified elsewhere are
9840d1d6 1843deprecated. This will not be allowed in Perl 5.32
0ac016fc
FC
1844
1845(D deprecated) You wrote something like
1846
1847 my $var;
1848 $sub = sub () { $var };
1849
1850but $var is referenced elsewhere and could be modified after the C<sub>
1851expression is evaluated. Either it is explicitly modified elsewhere
1852(C<$var = 3>) or it is passed to a subroutine or to an operator like
1853C<printf> or C<map>, which may or may not modify the variable.
1854
1855Traditionally, Perl has captured the value of the variable at that
1856point and turned the subroutine into a constant eligible for inlining.
1857In those cases where the variable can be modified elsewhere, this
1858breaks the behavior of closures, in which the subroutine captures
1859the variable itself, rather than its value, so future changes to the
1860variable are reflected in the subroutine's return value.
1861
9840d1d6
A
1862This usage is deprecated, and will no longer be allowed in Perl 5.32,
1863making it possible to change the behavior in the future.
0ac016fc
FC
1864
1865If you intended for the subroutine to be eligible for inlining, then
1866make sure the variable is not referenced elsewhere, possibly by
1867copying it:
1868
1869 my $var2 = $var;
1870 $sub = sub () { $var2 };
1871
1872If you do want this subroutine to be a closure that reflects future
1873changes to the variable that it closes over, add an explicit C<return>:
1874
1875 my $var;
1876 $sub = sub () { return $var };
1877
4cee8e80
CS
1878=item Constant subroutine %s redefined
1879
aeb94125
FC
1880(W redefine)(S) You redefined a subroutine which had previously
1881been eligible for inlining. See L<perlsub/"Constant Functions">
1882for commentary and workarounds.
4cee8e80 1883
9607fc9c
PP
1884=item Constant subroutine %s undefined
1885
be771a83
GS
1886(W misc) You undefined a subroutine which had previously been eligible
1887for inlining. See L<perlsub/"Constant Functions"> for commentary and
1888workarounds.
9607fc9c 1889
5a25739d
FC
1890=item Constant(%s) unknown
1891
1892(F) The parser found inconsistencies either while attempting
1893to define an overloaded constant, or when trying to find the
1894character name specified in the C<\N{...}> escape. Perhaps you
3ee1a09c 1895forgot to load the corresponding L<overload> pragma?
5a25739d 1896
4a873d7a
FC
1897=item :const is experimental
1898
1899(S experimental::const_attr) The "const" attribute is experimental.
1900If you want to use the feature, disable the warning with C<no warnings
1901'experimental::const_attr'>, but know that in doing so you are taking
1902the risk that your code may break in a future Perl version.
1903
b77472f9
FC
1904=item :const is not permitted on named subroutines
1905
1906(F) The "const" attribute causes an anonymous subroutine to be run and
465068b9 1907its value captured at the time that it is cloned. Named subroutines are
b77472f9
FC
1908not cloned like this, so the attribute does not make sense on them.
1909
e7ea3e70
IZ
1910=item Copy method did not return a reference
1911
6903afa2 1912(F) The method which overloads "=" is buggy. See
13a2d996 1913L<overload/Copy Constructor>.
e7ea3e70 1914
4aaa4757
FC
1915=item &CORE::%s cannot be called directly
1916
1917(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1918with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1919in this package cannot yet be called that way, but must be
1920called as barewords. Something like this will work:
1921
1922 BEGIN { *shove = \&CORE::push; }
1923 shove @array, 1,2,3; # pushes on to @array
1924
6798c92b
GS
1925=item CORE::%s is not a keyword
1926
1927(F) The CORE:: namespace is reserved for Perl keywords.
1928
675fa9ff
FC
1929=item Corrupted regexp opcode %d > %d
1930
1931(P) This is either an error in Perl, or, if you're using
1932one, your L<custom regular expression engine|perlreapi>. If not the
1933latter, report the problem through the L<perlbug> utility.
1934
a0d0e21e
LW
1935=item corrupted regexp pointers
1936
1937(P) The regular expression engine got confused by what the regular
1938expression compiler gave it.
1939
1940=item corrupted regexp program
1941
be771a83
GS
1942(P) The regular expression engine got passed a regexp program without a
1943valid magic number.
a0d0e21e 1944
de42a5a9 1945=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1946
1947(P) The malloc package that comes with Perl had an internal failure.
1948
49704364
LW
1949=item Count after length/code in unpack
1950
1951(F) You had an unpack template indicating a counted-length string, but
1952you have also specified an explicit size for the string. See
1953L<perlfunc/pack>.
1954
3f645a4e
FC
1955=item Declaring references is experimental
1956
1957(S experimental::declared_refs) This warning is emitted if you use
1958a reference constructor on the right-hand side of C<my>, C<state>, C<our>, or
1959C<local>. Simply suppress the warning if you want to use the feature, but
1960know that in doing so you are taking the risk of using an experimental
1961feature which may change or be removed in a future Perl version:
1962
1963 no warnings "experimental::declared_refs";
1964 use feature "declared_refs";
1965 $fooref = my \$foo;
1966
f2cccb4c
KW
1967=for comment
1968The following are used in lib/diagnostics.t for testing two =items that
1969share the same description. Changes here need to be propagated to there
1970
6651ba0b
FC
1971=item Deep recursion on anonymous subroutine
1972
a0d0e21e
LW
1973=item Deep recursion on subroutine "%s"
1974
be771a83
GS
1975(W recursion) This subroutine has called itself (directly or indirectly)
1976100 times more than it has returned. This probably indicates an
1977infinite recursion, unless you're writing strange benchmark programs, in
1978which case it indicates something else.
a0d0e21e 1979
aad1d01f
NC
1980This threshold can be changed from 100, by recompiling the F<perl> binary,
1981setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1982
e0e4a6e3
FC
1983=item (?(DEFINE)....) does not allow branches in regex; marked by
1984S<<-- HERE> in m/%s/
bcb95744 1985
6903afa2 1986(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1987most likely cause of this error is that you left out a parenthesis inside
1988of the C<....> part.
1989
6e8a73f2 1990The S<<-- HERE> shows whereabouts in the regular expression the problem was
bcb95744
FC
1991discovered.
1992
62658f4d
PM
1993=item %s defines neither package nor VERSION--version check failed
1994
1995(F) You said something like "use Module 42" but in the Module file
1996there are neither package declarations nor a C<$VERSION>.
1997
0ffcbc25
FC
1998=item delete argument is not a HASH or ARRAY element or slice
1999
4a0af295 2000(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
2001such as:
2002
2003 $foo{$bar}
2004 $ref->{"susie"}[12]
2005
2006or a hash or array slice, such as:
2007
2008 @foo[$bar, $baz, $xyzzy]
2009 @{$ref->[12]}{"susie", "queue"}
2010
cc0776d6
DIM
2011or a hash key/value or array index/value slice, such as:
2012
2013 %foo[$bar, $baz, $xyzzy]
2014 %{$ref->[12]}{"susie", "queue"}
2015
fc36a67e
PP
2016=item Delimiter for here document is too long
2017
be771a83
GS
2018(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
2019long for Perl to handle. You have to be seriously twisted to write code
2020that triggers this error.
fc36a67e 2021
c437f7ac 2022=item Deprecated use of my() in false conditional. This will be a fatal error in Perl 5.30
6d3b25aa 2023
fa816bf3
FC
2024(D deprecated) You used a declaration similar to C<my $x if 0>. There
2025has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 2026not to be cleared at scope exit when its declaration includes a false
6903afa2 2027conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 2028static variable. Since we intend to fix this bug, we don't want people
6903afa2 2029relying on this behavior. You can achieve a similar static effect by
6d3b25aa 2030declaring the variable in a separate block outside the function, eg
36fb85f3 2031
6d3b25aa
RGS
2032 sub f { my $x if 0; return $x++ }
2033
2034becomes
2035
2036 { my $x; sub f { return $x++ } }
2037
ea9d9ebc 2038Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 2039lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
2040
2041 sub f { state $x; return $x++ }
2042
c437f7ac
A
2043This use of C<my()> in a false conditional has been deprecated since
2044Perl 5.10, and it will become a fatal error in Perl 5.30.
2045
500ab966
RGS
2046=item DESTROY created new reference to dead object '%s'
2047
2048(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
2049just being DESTROYed. Perl is confused, and prefers to abort rather
2050than to create a dangling reference.
500ab966 2051
3cdd684c
TP
2052=item Did not produce a valid header
2053
3de20fbe 2054See L</500 Server error>.
3cdd684c 2055
6df41af2
GS
2056=item %s did not return a true value
2057
2058(F) A required (or used) file must return a true value to indicate that
2059it compiled correctly and ran its initialization code correctly. It's
2060traditional to end such a file with a "1;", though any true value would
2061do. See L<perlfunc/require>.
2062
cc507455 2063=item (Did you mean &%s instead?)
4633a7c4 2064
413ff9f6
FC
2065(W misc) You probably referred to an imported subroutine &FOO as $FOO or
2066some such.
4633a7c4 2067
cc507455 2068=item (Did you mean "local" instead of "our"?)
33633739 2069
52e3acf8 2070(W shadow) Remember that "our" does not localize the declared global
be771a83
GS
2071variable. You have declared it again in the same lexical scope, which
2072seems superfluous.
33633739 2073
cc507455 2074=item (Did you mean $ or @ instead of %?)
a0d0e21e 2075
be771a83
GS
2076(W) You probably said %hash{$key} when you meant $hash{$key} or
2077@hash{@keys}. On the other hand, maybe you just meant %hash and got
2078carried away.
748a9306 2079
7e1af8bc 2080=item Died
5f05dabc
PP
2081
2082(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 2083you called it with no args and C<$@> was empty.
5f05dabc 2084
3cdd684c
TP
2085=item Document contains no data
2086
3de20fbe 2087See L</500 Server error>.
3cdd684c 2088
62658f4d
PM
2089=item %s does not define %s::VERSION--version check failed
2090
2091(F) You said something like "use Module 42" but the Module did not
943fc58e 2092define a C<$VERSION>.
62658f4d 2093
49704364
LW
2094=item '/' does not take a repeat count
2095
2096(F) You cannot put a repeat count of any kind right after the '/' code.
2097See L<perlfunc/pack>.
2098
1c99110e 2099=item do "%s" failed, '.' is no longer in @INC; did you mean do "./%s"?
2a0461a3 2100
b28683c9 2101(D deprecated) Previously C< do "somefile"; > would search the current
1c99110e
DM
2102directory for the specified file. Since perl v5.26.0, F<.> has been
2103removed from C<@INC> by default, so this is no longer true. To search the
2104current directory (and only the current directory) you can write
2105C< do "./somefile"; >.
2a0461a3 2106
95cb0d72
FC
2107=item Don't know how to get file name
2108
2109(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
2110somehow called on another platform. This should not happen.
2111
4021c788 2112=item Don't know how to handle magic of type \%o
a0d0e21e
LW
2113
2114(P) The internal handling of magical variables has been cursed.
2115
2116=item do_study: out of memory
2117
2118(P) This should have been caught by safemalloc() instead.
2119
6df41af2
GS
2120=item (Do you need to predeclare %s?)
2121
56da5a46
RGS
2122(S syntax) This is an educated guess made in conjunction with the message
2123"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
2124name is being referenced that hasn't been declared yet. This may be
2125because of ordering problems in your file, or because of a missing
be771a83
GS
2126"sub", "package", "require", or "use" statement. If you're referencing
2127something that isn't defined yet, you don't actually have to define the
2128subroutine or package before the current location. You can use an empty
2129"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 2130
d8ff3e95 2131=item dump() must be written as CORE::dump() as of Perl 5.30
ac206dc8 2132
d8ff3e95
JK
2133(F) You used the obsolete C<dump()> built-in function. That was deprecated in
2134Perl 5.8.0. As of Perl 5.30 it must be written in fully qualified format:
2135C<CORE::dump()>.
30b17cc1
A
2136
2137See L<perlfunc/dump>.
ac206dc8 2138
84d78eb7
YO
2139=item dump is not supported
2140
2141(F) Your machine doesn't support dump/undump.
2142
a0d0e21e
LW
2143=item Duplicate free() ignored
2144
be771a83
GS
2145(S malloc) An internal routine called free() on something that had
2146already been freed.
a0d0e21e 2147
1109a392
MHM
2148=item Duplicate modifier '%c' after '%c' in %s
2149
35f0cd76
FC
2150(W unpack) You have applied the same modifier more than once after a
2151type in a pack template. See L<perlfunc/pack>.
1109a392 2152
4633a7c4
LW
2153=item elseif should be elsif
2154
fa816bf3
FC
2155(S syntax) There is no keyword "elseif" in Perl because Larry thinks
2156it's ugly. Your code will be interpreted as an attempt to call a method
2157named "elseif" for the class returned by the following block. This is
4633a7c4
LW
2158unlikely to be what you want.
2159
c30c479a
KW
2160=item Empty \%c in regex; marked by S<<-- HERE> in m/%s/
2161
ccad8842
KW
2162=item Empty \%c{}
2163
e0e4a6e3 2164=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 2165
e750debb
KW
2166(F) You used something like C<\b{}>, C<\B{}>, C<\o{}>, C<\p>, C<\P>, or
2167C<\x> without specifying anything for it to operate on.
2168
2169Unfortunately, for backwards compatibility reasons, an empty C<\x> is
2170legal outside S<C<use re 'strict'>> and expands to a NUL character.
ab13f0c7 2171
d9a91485
KW
2172=item Empty (?) without any modifiers in regex; marked by <-- HERE in m/%s/
2173
2174(W regexp) (only under C<S<use re 'strict'>>)
2175C<(?)> does nothing, so perhaps this is a typo.
2176
fd503f5c 2177=item ${^ENCODING} is no longer supported
a15a3d9b 2178
fd503f5c 2179(F) The special variable C<${^ENCODING}>, formerly used to implement
a15a3d9b
FC
2180the C<encoding> pragma, is no longer supported as of Perl 5.26.0.
2181
fd503f5c
DIM
2182Setting it to anything other than C<undef> is a fatal error as of Perl
21835.28.
ac641426 2184
85ab1d1d 2185=item entering effective %s failed
5ff3f7a4 2186
85ab1d1d 2187(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2188effective uids or gids failed.
2189
c038024b
RGS
2190=item %ENV is aliased to %s
2191
2192(F) You're running under taint mode, and the C<%ENV> variable has been
2193aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 2194program's environment. This is potentially insecure.
c038024b 2195
748a9306
LW
2196=item Error converting file specification %s
2197
5f05dabc 2198(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 2199specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
2200single form when it must operate on them directly. Either you've passed
2201an invalid file specification to Perl, or you've found a case the
2202conversion routines don't handle. Drat.
748a9306 2203
ad19ef22 2204=item Eval-group in insecure regular expression
e4d48cc9 2205
be771a83
GS
2206(F) Perl detected tainted data when trying to compile a regular
2207expression that contains the C<(?{ ... })> zero-width assertion, which
2208is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 2209
ad19ef22 2210=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 2211
be771a83
GS
2212(F) Perl tried to compile a regular expression containing the
2213C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
2214pattern contains interpolated values. Since that is a security risk,
2215it is not allowed. If you insist, you may still do this by using the
2216C<re 'eval'> pragma or by explicitly building the pattern from an
2217interpolated string at run time and using that in an eval(). See
2218L<perlre/(?{ code })>.
e4d48cc9 2219
ad19ef22 2220=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 2221
be771a83
GS
2222(F) A regular expression contained the C<(?{ ... })> zero-width
2223assertion, but that construct is only allowed when the C<use re 'eval'>
2224pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 2225
e0e4a6e3
FC
2226=item EVAL without pos change exceeded limit in regex; marked by
2227S<<-- HERE> in m/%s/
1a147d38
YO
2228
2229(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 2230any text. Restructure the pattern so that text is consumed.
1a147d38 2231
6e8a73f2 2232The S<<-- HERE> shows whereabouts in the regular expression the problem was
1a147d38
YO
2233discovered.
2234
fc36a67e
PP
2235=item Excessively long <> operator
2236
2237(F) The contents of a <> operator may not exceed the maximum size of a
2238Perl identifier. If you're just trying to glob a long list of
2239filenames, try using the glob() operator, or put the filenames into a
2240variable and glob that.
2241
ed9aa3b7
SG
2242=item exec? I'm not *that* kind of operating system
2243
af8bb25a 2244(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 2245OS. See L<perlport>.
ed9aa3b7 2246
c77da5ff 2247=item %sExecution of %s aborted due to compilation errors.
a0d0e21e
LW
2248
2249(F) The final summary message when a Perl compilation fails.
2250
0ffcbc25
FC
2251=item exists argument is not a HASH or ARRAY element or a subroutine
2252
4a0af295 2253(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
2254subroutine with an ampersand, such as:
2255
2256 $foo{$bar}
2257 $ref->{"susie"}[12]
2258 &do_something
2259
2260=item exists argument is not a subroutine name
2261
ccfc2567
FC
2262(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
2263and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 2264
a0d0e21e
LW
2265=item Exiting eval via %s
2266
be771a83
GS
2267(W exiting) You are exiting an eval by unconventional means, such as a
2268goto, or a loop control statement.
e476b1b5
GS
2269
2270=item Exiting format via %s
2271
9a2ff54b 2272(W exiting) You are exiting a format by unconventional means, such as a
be771a83 2273goto, or a loop control statement.
a0d0e21e 2274
0a753a76
PP
2275=item Exiting pseudo-block via %s
2276
be771a83
GS
2277(W exiting) You are exiting a rather special block construct (like a
2278sort block or subroutine) by unconventional means, such as a goto, or a
2279loop control statement. See L<perlfunc/sort>.
0a753a76 2280
a0d0e21e
LW
2281=item Exiting subroutine via %s
2282
be771a83
GS
2283(W exiting) You are exiting a subroutine by unconventional means, such
2284as a goto, or a loop control statement.
a0d0e21e
LW
2285
2286=item Exiting substitution via %s
2287
be771a83
GS
2288(W exiting) You are exiting a substitution by unconventional means, such
2289as a return, a goto, or a loop control statement.
a0d0e21e 2290
e0e4a6e3 2291=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 2292
675fa9ff 2293(F) You wrote something like
c608e803
KW
2294
2295 (?13
2296
2297to denote a capturing group of the form
2298L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
2299but omitted the C<")">.
2300
c9ffefcc
FC
2301=item Expecting close paren for nested extended charclass in regex; marked
2302by <-- HERE in m/%s/
2303
2304(F) While parsing a nested extended character class like:
2305
2306 (?[ ... (?flags:(?[ ... ])) ... ])
2307 ^
2308
2309we expected to see a close paren ')' (marked by ^) but did not.
2310
2311=item Expecting close paren for wrapper for nested extended charclass in
2312regex; marked by <-- HERE in m/%s/
2313
2314(F) While parsing a nested extended character class like:
2315
2316 (?[ ... (?flags:(?[ ... ])) ... ])
2317 ^
2318
2319we expected to see a close paren ')' (marked by ^) but did not.
2320
e0e4a6e3 2321=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 2322
8b6fbf55
FC
2323(F) The C<(?[...])> extended character class regular expression construct
2324only allows character classes (including character class escapes like
2325C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
2326containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
2327This allows a regular expression containing just C<(?[...])> to be
2328interpolated. If you see this error message, then you probably
2329have some other C<(?...)> construct inside your character class. See
2330L<perlrecharclass/Extended Bracketed Character Classes>.
2331
baabe3fb 2332=item Experimental aliasing via reference not enabled
1f8155a2 2333
baabe3fb 2334(F) To do aliasing via references, you must first enable the feature:
1f8155a2 2335
baabe3fb
FC
2336 no warnings "experimental::refaliasing";
2337 use feature "refaliasing";
1f8155a2
FC
2338 \$x = \$y;
2339
74d1b2e4
FC
2340=item Experimental %s on scalar is now forbidden
2341
2342(F) An experimental feature added in Perl 5.14 allowed C<each>, C<keys>,
2343C<push>, C<pop>, C<shift>, C<splice>, C<unshift>, and C<values> to be called with a
2344scalar argument. This experiment is considered unsuccessful, and
2345has been removed. The C<postderef> feature may meet your needs better.
2346
30d9c59b
Z
2347=item Experimental subroutine signatures not enabled
2348
2349(F) To use subroutine signatures, you must first enable them:
2350
caa35032 2351 no warnings "experimental::signatures";
30d9c59b
Z
2352 use feature "signatures";
2353 sub foo ($left, $right) { ... }
2354
7b8d334a
GS
2355=item Explicit blessing to '' (assuming package main)
2356
be771a83
GS
2357(W misc) You are blessing a reference to a zero length string. This has
2358the effect of blessing the reference into the package main. This is
2359usually not what you want. Consider providing a default target package,
2360e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2361
6df41af2
GS
2362=item %s: Expression syntax
2363
be771a83
GS
2364(A) You've accidentally run your script through B<csh> instead of Perl.
2365Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2366
2367=item %s failed--call queue aborted
2368
3c10abe3
AG
2369(F) An untrapped exception was raised while executing a UNITCHECK,
2370CHECK, INIT, or END subroutine. Processing of the remainder of the
2371queue of such routines has been prematurely ended.
6df41af2 2372
e0d4aead 2373=item Failed to close in-place work file %s: %s
502aca56
TC
2374
2375(F) Closing an output file from in-place editing, as with the C<-i>
2376command-line switch, failed.
2377
e0e4a6e3 2378=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2379
98d31c73 2380(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2381character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2382in your false range is interpreted as a literal "-". In a C<(?[...])>
2383construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2384the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2385the problem was discovered. See L<perlre>.
73b437c8 2386
1b1ee2ef 2387=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2388
be771a83
GS
2389(P) An error peculiar to VMS. Something untoward happened in a VMS
2390system service or RTL routine; Perl's exit status should provide more
2391details. The filename in "at %s" and the line number in "line %d" tell
2392you which section of the Perl source code is distressed.
a0d0e21e
LW
2393
2394=item fcntl is not implemented
2395
2396(F) Your machine apparently doesn't implement fcntl(). What is this, a
2397PDP-11 or something?
2398
22846ab4
AB
2399=item FETCHSIZE returned a negative value
2400
2401(F) A tied array claimed to have a negative number of elements, which
2402is not possible.
2403
f337b084
TH
2404=item Field too wide in 'u' format in pack
2405
d8b5cc61 2406(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2407which can't encode values above 63. So there is no point in asking for
2408a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2409C<u63> as the format.
f337b084 2410
a0e213fc
A
2411=item File::Glob::glob() will disappear in perl 5.30. Use File::Glob::bsd_glob() instead.
2412
2413(D deprecated) C<< File::Glob >> has a function called C<< glob >>, which
2414just calls C<< bsd_glob >>. However, its prototype is different from the
2415prototype of C<< CORE::glob >>, and hence, C<< File::Glob::glob >> should
2416not be used.
2417
2418C<< File::Glob::glob() >> was deprecated in perl 5.8.0. A deprecation
2419message was issued from perl 5.26.0 onwards, and the function will
2420disappear in perl 5.30.0.
2421
2422Code using C<< File::Glob::glob() >> should call
2423C<< File::Glob::bsd_glob() >> instead.
2424
af8c498a 2425=item Filehandle %s opened only for input
a0d0e21e 2426
6c8d78fb
HS
2427(W io) You tried to write on a read-only filehandle. If you intended
2428it to be a read-write filehandle, you needed to open it with "+<" or
2429"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2430write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2431
af8c498a 2432=item Filehandle %s opened only for output
a0d0e21e 2433
6c8d78fb
HS
2434(W io) You tried to read from a filehandle opened only for writing, If
2435you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2436with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2437read from the file, use "<". See L<perlfunc/open>. Another possibility
2438is that you attempted to open filedescriptor 0 (also known as STDIN) for
2439output (maybe you closed STDIN earlier?).
97828cef
RGS
2440
2441=item Filehandle %s reopened as %s only for input
2442
2443(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2444as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2445previously.
2446
2447=item Filehandle STDIN reopened as %s only for output
2448
2449(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2450as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2451
2452=item Final $ should be \$ or $name
2453
2454(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2455a literal dollar sign, or was meant to introduce a variable name that
2456happens to be missing. So you have to put either the backslash or the
2457name.
a0d0e21e 2458
56e90b21
GS
2459=item flock() on closed filehandle %s
2460
be771a83 2461(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2462some time before now. Check your control flow. flock() operates on
be771a83
GS
2463filehandles. Are you attempting to call flock() on a dirhandle by the
2464same name?
56e90b21 2465
6df41af2
GS
2466=item Format not terminated
2467
2468(F) A format must be terminated by a line with a solitary dot. Perl got
2469to the end of your file without finding such a line.
2470
a0d0e21e
LW
2471=item Format %s redefined
2472
e476b1b5 2473(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2474
2475 {
271595cc 2476 no warnings 'redefine';
a0d0e21e
LW
2477 eval "format NAME =...";
2478 }
2479
a0d0e21e
LW
2480=item Found = in conditional, should be ==
2481
e476b1b5 2482(W syntax) You said
a0d0e21e
LW
2483
2484 if ($foo = 123)
2485
2486when you meant
2487
2488 if ($foo == 123)
2489
2490(or something like that).
2491
6df41af2
GS
2492=item %s found where operator expected
2493
56da5a46
RGS
2494(S syntax) The Perl lexer knows whether to expect a term or an operator.
2495If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2496operator, it gives you this warning. Usually it indicates that an
2497operator or delimiter was omitted, such as a semicolon.
6df41af2 2498
a0d0e21e
LW
2499=item gdbm store returned %d, errno %d, key "%s"
2500
2501(S) A warning from the GDBM_File extension that a store failed.
2502
2503=item gethostent not implemented
2504
2505(F) Your C library apparently doesn't implement gethostent(), probably
2506because if it did, it'd feel morally obligated to return every hostname
2507on the Internet.
2508
69282e91 2509=item get%sname() on closed socket %s
a0d0e21e 2510
be771a83
GS
2511(W closed) You tried to get a socket or peer socket name on a closed
2512socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2513
748a9306
LW
2514=item getpwnam returned invalid UIC %#o for user "%s"
2515
2516(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2517C<getpwnam> operator returned an invalid UIC.
2518
6df41af2
GS
2519=item getsockopt() on closed socket %s
2520
be771a83
GS
2521(W closed) You tried to get a socket option on a closed socket. Did you
2522forget to check the return value of your socket() call? See
6df41af2
GS
2523L<perlfunc/getsockopt>.
2524
0f539b13
BF
2525=item given is experimental
2526
7896dde7
Z
2527(S experimental::smartmatch) C<given> depends on smartmatch, which
2528is experimental, so its behavior may change or even be removed
2529in any future release of perl. See the explanation under
2530L<perlsyn/Experimental Details on given and when>.
0f539b13 2531
68567d27
FC
2532=item Global symbol "%s" requires explicit package name (did you forget to
2533declare "my %s"?)
6df41af2 2534
a4edf47d 2535(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2536that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2537declared beforehand using "our", or explicitly qualified to say
2538which package the global variable is in (using "::").
6df41af2 2539
e476b1b5
GS
2540=item glob failed (%s)
2541
5ead438e 2542(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2543for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2544pattern that caused the external program to fail and exit with a
be771a83 2545nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2546resulted in a coredump, this may also mean that your csh (C shell)
2547is broken. If so, you should change all of the csh-related variables
2548in config.sh: If you have tcsh, make the variables refer to it as
2549if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2550all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2551think csh is missing. In either case, after editing config.sh, run
75b44862 2552C<./Configure -S> and rebuild Perl.
e476b1b5 2553
a0d0e21e
LW
2554=item Glob not terminated
2555
2556(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2557a term, so it's looking for the corresponding right angle bracket, and
2558not finding it. Chances are you left some needed parentheses out
2559earlier in the line, and you really meant a "less than".
a0d0e21e 2560
b35b96b6
JH
2561=item gmtime(%f) failed
2562
2563(W overflow) You called C<gmtime> with a number that it could not handle:
2564too large, too small, or NaN. The returned value is C<undef>.
2565
bcd05b94 2566=item gmtime(%f) too large
8b56d6ff 2567
e9200be3 2568(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2569it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2570date. This warning is also triggered with NaN (the special
fc003d4b
MS
2571not-a-number value).
2572
bcd05b94 2573=item gmtime(%f) too small
fc003d4b 2574
e9200be3 2575(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2576it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2577
6df41af2 2578=item Got an error from DosAllocMem
a0d0e21e 2579
6df41af2
GS
2580(P) An error peculiar to OS/2. Most probably you're using an obsolete
2581version of Perl, and this should not happen anyway.
a0d0e21e
LW
2582
2583=item goto must have label
2584
2585(F) Unlike with "next" or "last", you're not allowed to goto an
2586unspecified destination. See L<perlfunc/goto>.
2587
6651ba0b
FC
2588=item Goto undefined subroutine%s
2589
2590(F) You tried to call a subroutine with C<goto &sub> syntax, but
2591the indicated subroutine hasn't been defined, or if it was, it
2592has since been undefined.
2593
6fbc9859 2594=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2595S<<-- HERE> in m/%s/
1f4f6bf1
YO
2596
2597(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2598they must start with a non-digit word character. A common cause of
2599this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2600
5a25739d
FC
2601=item ()-group starts with a count
2602
2603(F) A ()-group started with a count. A count is supposed to follow
2604something: a template character or a ()-group. See L<perlfunc/pack>.
2605
fe13d51d 2606=item %s had compilation errors.
6df41af2
GS
2607
2608(F) The final summary message when a C<perl -c> fails.
2609
a0d0e21e
LW
2610=item Had to create %s unexpectedly
2611
be771a83
GS
2612(S internal) A routine asked for a symbol from a symbol table that ought
2613to have existed already, but for some reason it didn't, and had to be
2614created on an emergency basis to prevent a core dump.
a0d0e21e 2615
6df41af2
GS
2616=item %s has too many errors
2617
2618(F) The parser has given up trying to parse the program after 10 errors.
2619Further error messages would likely be uninformative.
2620
61e61fbc
JH
2621=item Hexadecimal float: exponent overflow
2622
d8f2b442 2623(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2624than the floating point supports.
2625
2626=item Hexadecimal float: exponent underflow
2627
d8f2b442 2628(W overflow) The hexadecimal floating point has a smaller exponent
b6d9b423
JH
2629than the floating point supports. With the IEEE 754 floating point,
2630this may also mean that the subnormals (formerly known as denormals)
2631are being used, which may or may not be an error.
61e61fbc 2632
5488d373 2633=item Hexadecimal float: internal error (%s)
cf4f6003
JH
2634
2635(F) Something went horribly bad in hexadecimal float handling.
2636
61e61fbc
JH
2637=item Hexadecimal float: mantissa overflow
2638
2639(W overflow) The hexadecimal floating point literal had more bits in
2640the mantissa (the part between the 0x and the exponent, also known as
2641the fraction or the significand) than the floating point supports.
2642
40bca5ae
JH
2643=item Hexadecimal float: precision loss
2644
2645(W overflow) The hexadecimal floating point had internally more
2646digits than could be output. This can be caused by unsupported
2647long double formats, or by 64-bit integers not being available
2648(needed to retrieve the digits under some configurations).
2649
2650=item Hexadecimal float: unsupported long double format
2651
2652(F) You have configured Perl to use long doubles but
d8f2b442 2653the internals of the long double format are unknown;
40bca5ae
JH
2654therefore the hexadecimal float output is impossible.
2655
252aa082
JH
2656=item Hexadecimal number > 0xffffffff non-portable
2657
e476b1b5 2658(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2659(4294967295) and therefore non-portable between systems. See
2660L<perlport> for more on portability concerns.
252aa082 2661
8903cb82
PP
2662=item Identifier too long
2663
2664(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2665about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2666names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2667of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2668
e0e4a6e3
FC
2669=item Ignoring zero length \N{} in character class in regex; marked by
2670S<<-- HERE> in m/%s/
fc8cd66c 2671
f3ba6905 2672(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
0f44b2a5
FC
2673zero-length sequence. When such an escape is used in a character
2674class its behavior is not well defined. Check that the correct
2675escape has been used, and the correct charname handler is in scope.
fc8cd66c 2676
283151b7 2677=item Illegal binary digit '%c'
f675dbe5 2678
6df41af2 2679(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2680
6df41af2 2681=item Illegal binary digit %s ignored
a0d0e21e 2682
be771a83
GS
2683(W digit) You may have tried to use a digit other than 0 or 1 in a
2684binary number. Interpretation of the binary number stopped before the
2685offending digit.
a0d0e21e 2686
6597eb22
FC
2687=item Illegal character after '_' in prototype for %s : %s
2688
e4d150f1
FC
2689(W illegalproto) An illegal character was found in a prototype
2690declaration. The '_' in a prototype must be followed by a ';',
2691indicating the rest of the parameters are optional, or one of '@'
2692or '%', since those two will accept 0 or more final parameters.
6597eb22 2693
b913d0b8
FC
2694=item Illegal character \%o (carriage return)
2695
2696(F) Perl normally treats carriage returns in the program text as
2697it would any other whitespace, which means you should never see
2698this error when Perl was built using standard options. For some
2699reason, your version of Perl appears to have been built without
2700this support. Talk to your Perl administrator.
2701
bb6b75cd 2702=item Illegal character following sigil in a subroutine signature
d3d9da4a
DM
2703
2704(F) A parameter in a subroutine signature contained an unexpected character
d4e5761f
FC
2705following the C<$>, C<@> or C<%> sigil character. Normally the sigil
2706should be followed by the variable name or C<=> etc. Perhaps you are
d3d9da4a
DM
2707trying use a prototype while in the scope of C<use feature 'signatures'>?
2708For example:
2709
2710 sub foo ($$) {} # legal - a prototype
2711
2712 use feature 'signatures;
2713 sub foo ($$) {} # illegal - was expecting a signature
2714 sub foo ($a, $b)
2715 :prototype($$) {} # legal
2716
2717
d37a9538
ST
2718=item Illegal character in prototype for %s : %s
2719
197afce1 2720(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2721Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2722Perhaps you were trying to write a subroutine signature but didn't enable
2723that feature first (C<use feature 'signatures'>), so your signature was
2724instead interpreted as a bad prototype.
d37a9538 2725
904d85c5
RGS
2726=item Illegal declaration of anonymous subroutine
2727
2728(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2729you must always specify a block of code. See L<perlsub>.
904d85c5 2730
8e742a20
MHM
2731=item Illegal declaration of subroutine %s
2732
6903afa2 2733(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2734
a0d0e21e
LW
2735=item Illegal division by zero
2736
be771a83
GS
2737(F) You tried to divide a number by 0. Either something was wrong in
2738your logic, or you need to put a conditional in to guard against
2739meaningless input.
a0d0e21e 2740
6df41af2
GS
2741=item Illegal hexadecimal digit %s ignored
2742
be771a83
GS
2743(W digit) You may have tried to use a character other than 0 - 9 or
2744A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2745number stopped before the illegal character.
6df41af2 2746
a0d0e21e
LW
2747=item Illegal modulus zero
2748
be771a83
GS
2749(F) You tried to divide a number by 0 to get the remainder. Most
2750numbers don't take to this kindly.
a0d0e21e 2751
6df41af2 2752=item Illegal number of bits in vec
399388f4 2753
6df41af2
GS
2754(F) The number of bits in vec() (the third argument) must be a power of
2755two from 1 to 32 (or 64, if your platform supports that).
399388f4 2756
283151b7 2757=item Illegal octal digit '%c'
a0d0e21e 2758
d1be9408 2759(F) You used an 8 or 9 in an octal number.
a0d0e21e 2760
399388f4 2761=item Illegal octal digit %s ignored
748a9306 2762
d1be9408 2763(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2764Interpretation of the octal number stopped before the 8 or 9.
748a9306 2765
ecc6274e
FC
2766=item Illegal operator following parameter in a subroutine signature
2767
2768(F) A parameter in a subroutine signature, was followed by something
2769other than C<=> introducing a default, C<,> or C<)>.
2770
2771 use feature 'signatures';
2772 sub foo ($=1) {} # legal
2773 sub foo ($a = 1) {} # legal
2774 sub foo ($a += 1) {} # illegal
2775 sub foo ($a == 1) {} # illegal
2776
e0e4a6e3 2777=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2778
675fa9ff 2779(F) You wrote something like
c608e803
KW
2780
2781 (?+foo)
2782
2783The C<"+"> is valid only when followed by digits, indicating a
2784capturing group. See
2785L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2786
375ed12a
JH
2787=item Illegal suidscript
2788
2789(F) The script run under suidperl was somehow illegal.
2790
fe13d51d 2791=item Illegal switch in PERL5OPT: -%c
6ff81951 2792
6df41af2 2793(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2794following switches: B<-[CDIMUdmtw]>.
6ff81951 2795
4003ea29
KW
2796=item Illegal user-defined property name
2797
2798(F) You specified a Unicode-like property name in a regular expression
2799pattern (using C<\p{}> or C<\P{}>) that Perl knows isn't an official
2800Unicode property, and was likely meant to be a user-defined property
2801name, but it can't be one of those, as they must begin with either C<In>
2802or C<Is>. Check the spelling. See also
2803L</Can't find Unicode property definition "%s">.
2804
6df41af2 2805=item Ill-formed CRTL environ value "%s"
81e118e0 2806
75b44862 2807(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2808internal environ array, and encountered an element without the C<=>
2809delimiter used to separate keys from values. The element is ignored.
09bef843 2810
6df41af2 2811=item Ill-formed message in prime_env_iter: |%s|
54310121 2812
be771a83
GS
2813(W internal) A warning peculiar to VMS. Perl tried to read a logical
2814name or CLI symbol definition when preparing to iterate over %ENV, and
2815didn't see the expected delimiter between key and value, so the line was
2816ignored.
54310121 2817
6df41af2 2818=item (in cleanup) %s
9607fc9c 2819
be771a83
GS
2820(W misc) This prefix usually indicates that a DESTROY() method raised
2821the indicated exception. Since destructors are usually called by the
2822system at arbitrary points during execution, and often a vast number of
2823times, the warning is issued only once for any number of failures that
2824would otherwise result in the same message being repeated.
6df41af2 2825
be771a83
GS
2826Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2827also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2828
e0e4a6e3
FC
2829=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2830in m/%s/
0d0b4b3b 2831
675fa9ff 2832(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2833expression inside the construct was completely empty, or if there are
2834too many or few operands for the number of operators. Perl is not smart
2835enough to give you a more precise indication as to what is wrong.
2836
6fbc9859
MH
2837=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2838parent '%s'
2c7d6b9c
RGS
2839
2840(F) The method resolution order (MRO) of the given class is not
2841C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2842documentation in L<mro> for more information.
2843
cdd6375d
MH
2844=item Indentation on line %d of here-doc doesn't match delimiter
2845
2846(F) You have an indented here-document where one or more of its lines
2847have whitespace at the beginning that does not match the closing
2848delimiter.
2849
2850For example, line 2 below is wrong because it does not have at least
28512 spaces, but lines 1 and 3 are fine because they have at least 2:
2852
2853 if ($something) {
2854 print <<~EOF;
2855 Line 1
2856 Line 2 not
2857 Line 3
2858 EOF
2859 }
2860
2861Note that tabs and spaces are compared strictly, meaning 1 tab will
2862not match 8 spaces.
2863
6a2ed79a 2864=item Infinite recursion in regex
1a147d38
YO
2865
2866(F) You used a pattern that references itself without consuming any input
6903afa2 2867text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2868either consume text or fail.
2869
714f94d1
FC
2870=item Infinite recursion via empty pattern
2871
2872(F) You tried to use the empty pattern inside of a regex code block,
2873for instance C</(?{ s!!! })/>, which resulted in re-executing
2874the same pattern, which is an infinite loop which is broken by
2875throwing an exception.
2876
f99042c8 2877=item Initialization of state variables in list currently forbidden
6dbe9451 2878
f99042c8
Z
2879(F) C<state> only permits initializing a single variable, specified
2880without parentheses. So C<state $a = 42> and C<state @a = qw(a b c)> are
2881allowed, but not C<state ($a) = 42> or C<(state $a) = 42>. To initialize
2882more than one C<state> variable, initialize them one at a time.
6dbe9451 2883
2186f873
FC
2884=item %%s[%s] in scalar context better written as $%s[%s]
2885
2886(W syntax) In scalar context, you've used an array index/value slice
2887(indicated by %) to select a single element of an array. Generally
2888it's better to ask for a scalar value (indicated by $). The difference
2889is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2890returns and when evaluating its argument, while C<%foo[&bar]> provides
2891a list context to its subscript, which can do weird things if you're
2892expecting only one subscript. When called in list context, it also
2893returns the index (what C<&bar> returns) in addition to the value.
2894
2895=item %%s{%s} in scalar context better written as $%s{%s}
2896
2897(W syntax) In scalar context, you've used a hash key/value slice
2898(indicated by %) to select a single element of a hash. Generally it's
2899better to ask for a scalar value (indicated by $). The difference
2900is that C<$foo{&bar}> always behaves like a scalar, both in the value
2901it returns and when evaluating its argument, while C<@foo{&bar}> and
2902provides a list context to its subscript, which can do weird things
2903if you're expecting only one subscript. When called in list context,
2904it also returns the key in addition to the value.
2905
a0d0e21e
LW
2906=item Insecure dependency in %s
2907
8b1a09fc 2908(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2909The tainting mechanism is turned on when you're running setuid or
2910setgid, or when you specify B<-T> to turn it on explicitly. The
2911tainting mechanism labels all data that's derived directly or indirectly
2912from the user, who is considered to be unworthy of your trust. If any
2913such data is used in a "dangerous" operation, you get this error. See
2914L<perlsec> for more information.
a0d0e21e
LW
2915
2916=item Insecure directory in %s
2917
be771a83
GS
2918(F) You can't use system(), exec(), or a piped open in a setuid or
2919setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2920the world. Also, the PATH must not contain any relative directory.
2921See L<perlsec>.
a0d0e21e 2922
62f468fc 2923=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2924
2925(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2926setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2927C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2928supplied (or potentially supplied) by the user. The script must set
2929the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2930
0e9be77f
DM
2931=item Insecure user-defined property %s
2932
2933(F) Perl detected tainted data when trying to compile a regular
2934expression that contains a call to a user-defined character property
2935function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2936See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2937
b9ef414d
FC
2938=item Integer overflow in format string for %s
2939
2940(F) The indexes and widths specified in the format string of C<printf()>
2941or C<sprintf()> are too large. The numbers must not overflow the size of
2942integers for your architecture.
2943
a7ae9550
GS
2944=item Integer overflow in %s number
2945
35928bc5 2946(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2947either as a literal or as an argument to hex() or oct() is too big for
2948your architecture, and has been converted to a floating point number.
2949On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2950representable without overflow is 0xFFFFFFFF, 037777777777, or
29510b11111111111111111111111111111111 respectively. Note that Perl
2952transparently promotes all numbers to a floating point representation
2953internally--subject to loss of precision errors in subsequent
2954operations.
bbce6d69 2955
fc89ca81
FC
2956=item Integer overflow in srand
2957
2958(S overflow) The number you have passed to srand is too big to fit
2959in your architecture's integer representation. The number has been
2960replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2961architectures). This means you may be getting less randomness than
2962you expect, because different random seeds above the maximum will
2963return the same sequence of random numbers.
2964
46314c13
JP
2965=item Integer overflow in version
2966
18da5252
FC
2967=item Integer overflow in version %d
2968
784d71ed
FC
2969(W overflow) Some portion of a version initialization is too large for
2970the size of integers for your architecture. This is not a warning
f084e84f 2971because there is no rational reason for a version to try and use an
784d71ed
FC
2972element larger than typically 2**32. This is usually caused by trying
2973to use some odd mathematical operation as a version, like 100/9.
46314c13 2974
e0e4a6e3 2975=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2976
2977(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2978The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2979discovered.
2980
748a9306
LW
2981=item Internal inconsistency in tracking vforks
2982
be771a83
GS
2983(S) A warning peculiar to VMS. Perl keeps track of the number of times
2984you've called C<fork> and C<exec>, to determine whether the current call
2985to C<exec> should affect the current script or a subprocess (see
2986L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2987Perl is making a guess and treating this C<exec> as a request to
2988terminate the Perl script and execute the specified command.
748a9306 2989
870978ae
FC
2990=item internal %<num>p might conflict with future printf extensions
2991
2992(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2993formatting follows a slightly different set of rules when called from
2994C or XS code. Specifically, formats consisting of digits followed
2995by "p" (e.g., "%7p") are reserved for future use. If you see this
2996message, then an XS module tried to call that routine with one such
2997reserved format.
2998
e0e4a6e3 2999=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 3000
fa816bf3 3001(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 3002S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 3003discovered.
a0d0e21e 3004
6df41af2
GS
3005=item %s (...) interpreted as function
3006
75b44862 3007(W syntax) You've run afoul of the rule that says that any list operator
be771a83 3008followed by parentheses turns into a function, with all the list
64977eb6 3009operators arguments found inside the parentheses. See
13a2d996 3010L<perlop/Terms and List Operators (Leftward)>.
6df41af2 3011
f51551f7
FC
3012=item In '(?...)', the '(' and '?' must be adjacent in regex;
3013marked by S<<-- HERE> in m/%s/
3014
3015(F) The two-character sequence C<"(?"> in this context in a regular
3016expression pattern should be an indivisible token, with nothing
3017intervening between the C<"("> and the C<"?">, but you separated them
3018with whitespace.
3019
d9790612 3020=item In '(*...)', the '(' and '*' must be adjacent in regex;
edf23316
FC
3021marked by S<<-- HERE> in m/%s/
3022
d9790612 3023(F) The two-character sequence C<"(*"> in this context in a regular
edf23316 3024expression pattern should be an indivisible token, with nothing
d9790612
KW
3025intervening between the C<"("> and the C<"*">, but you separated them.
3026Fix the pattern and retry.
edf23316 3027
09bef843
SB
3028=item Invalid %s attribute: %s
3029
a4a4c9e2 3030(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
3031by Perl or by a user-supplied handler. See L<attributes>.
3032
3033=item Invalid %s attributes: %s
3034
a4a4c9e2 3035(F) The indicated attributes for a subroutine or variable were not
be771a83 3036recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 3037
e0e4a6e3
FC
3038=item Invalid character in charnames alias definition; marked by
3039S<<-- HERE> in '%s
225fb84f
KW
3040
3041(F) You tried to create a custom alias for a character name, with
3042the C<:alias> option to C<use charnames> and the specified character in
3043the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
3044
c8028aa6
TC
3045=item Invalid \0 character in %s for %s: %s\0%s
3046
fa3234e3
FC
3047(W syscalls) Embedded \0 characters in pathnames or other system call
3048arguments produce a warning as of 5.20. The parts after the \0 were
3049formerly ignored by system calls.
c8028aa6 3050
e0e4a6e3 3051=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
3052
3053(F) Only certain characters are valid for character names. The
3054indicated one isn't. See L<charnames/CUSTOM ALIASES>.
3055
c635e13b
PP
3056=item Invalid conversion in %s: "%s"
3057
be771a83
GS
3058(W printf) Perl does not understand the given format conversion. See
3059L<perlfunc/sprintf>.
c635e13b 3060
e0e4a6e3
FC
3061=item Invalid escape in the specified encoding in regex; marked by
3062S<<-- HERE> in m/%s/
9e08bc66 3063
98d31c73 3064(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
3065didn't correspond to a single character through the conversion
3066from the encoding specified by the encoding pragma.
98d31c73
FC
3067The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
3068instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 3069The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
3070escape was discovered.
3071
8149aa9f
FC
3072=item Invalid hexadecimal number in \N{U+...}
3073
e0e4a6e3
FC
3074=item Invalid hexadecimal number in \N{U+...} in regex; marked by
3075S<<-- HERE> in m/%s/
aec0ef10 3076
8149aa9f 3077(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
3078number. Either it is empty, or you tried to use a character other than
30790 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 3080
6651ba0b
FC
3081=item Invalid module name %s with -%c option: contains single ':'
3082
3083(F) The module argument to perl's B<-m> and B<-M> command-line options
3084cannot contain single colons in the module name, but only in the
3085arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
3086B<-MFoo:Bar=baz> is not.
3087
2c7d6b9c
RGS
3088=item Invalid mro name: '%s'
3089
162a3e34
FC
3090(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
3091where C<foo> is not a valid method resolution order (MRO). Currently,
3092the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
3093a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 3094
40e4140b
FC
3095=item Invalid negative number (%s) in chr
3096
3097(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 3098not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
3099character (U+FFFD).
3100
74d1b2e4
FC
3101=item Invalid number '%s' for -C option.
3102
3103(F) You supplied a number to the -C option that either has extra leading
3104zeroes or overflows perl's unsigned integer representation.
3105
6651ba0b
FC
3106=item invalid option -D%c, use -D'' to see choices
3107
8ff21bfe
FC
3108(S debugging) Perl was called with invalid debugger flags. Call perl
3109with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 3110See also L<perlrun/-Dletters>.
6651ba0b 3111
6e8a73f2 3112=item Invalid quantifier in {,} in regex; marked by S<<-- HERE> in m/%s/
35cd12d1
HS
3113
3114(F) The pattern looks like a {min,max} quantifier, but the min or max
3115could not be parsed as a valid number - either it has leading zeroes,
3116or it represents too big a number to cope with. The S<<-- HERE> shows
3117where in the regular expression the problem was discovered. See L<perlre>.
3118
e0e4a6e3 3119=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
3120
3121(F) The range specified in a character class had a minimum character
7253e4e3
RK
3122greater than the maximum character. One possibility is that you forgot the
3123C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 3124up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 3125problem was discovered. See L<perlre>.
6df41af2 3126
d1573ac7 3127=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
3128
3129(F) The range specified in the tr/// or y/// operator had a minimum
3130character greater than the maximum character. See L<perlop>.
3131
09bef843
SB
3132=item Invalid separator character %s in attribute list
3133
0120eecf 3134(F) Something other than a colon or whitespace was seen between the
be771a83
GS
3135elements of an attribute list. If the previous attribute had a
3136parenthesised parameter list, perhaps that list was terminated too soon.
3137See L<attributes>.
09bef843 3138
b4581f09
JH
3139=item Invalid separator character %s in PerlIO layer specification %s
3140
2bfc5f71
FC
3141(W layer) When pushing layers onto the Perl I/O system, something other
3142than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
3143If the previous attribute had a parenthesised parameter list, perhaps that
3144list was terminated too soon.
3145
2c86d456
DG
3146=item Invalid strict version format (%s)
3147
fa816bf3 3148(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
3149A "strict" version number is a positive decimal number (integer or
3150decimal-fraction) without exponentiation or else a dotted-decimal
3151v-string with a leading 'v' character and at least three components.
a6485a24 3152The parenthesized text indicates which criteria were not met.
2c86d456
DG
3153See the L<version> module for more details on allowed version formats.
3154
49704364 3155=item Invalid type '%s' in %s
96e4d5b1 3156
49704364
LW
3157(F) The given character is not a valid pack or unpack type.
3158See L<perlfunc/pack>.
6728c851 3159
49704364 3160(W) The given character is not a valid pack or unpack type but used to be
75b44862 3161silently ignored.
96e4d5b1 3162
2c86d456
DG
3163=item Invalid version format (%s)
3164
fa816bf3 3165(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
3166A "lax" version number is a positive decimal number (integer or
3167decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
3168v-string. If the v-string has fewer than three components, it
3169must have a leading 'v' character. Otherwise, the leading 'v' is
3170optional. Both decimal and dotted-decimal versions may have a
3171trailing "alpha" component separated by an underscore character
3172after a fractional or dotted-decimal component. The parenthesized
3173text indicates which criteria were not met. See the L<version> module
3174for more details on allowed version formats.
46314c13 3175
798ae1b7
DG
3176=item Invalid version object
3177
fa816bf3
FC
3178(F) The internal structure of the version object was invalid.
3179Perhaps the internals were modified directly in some way or
3180an arbitrary reference was blessed into the "version" class.
798ae1b7 3181
cd209d9d 3182=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 3183marked by S<<-- HERE> in m/%s/
675fa9ff 3184
edf23316
FC
3185(F) The two-character sequence C<"(*"> in this context in a regular
3186expression pattern should be an indivisible token, with nothing
3187intervening between the C<"("> and the C<"*">, but you separated them.
675fa9ff 3188
a0d0e21e
LW
3189=item ioctl is not implemented
3190
3191(F) Your machine apparently doesn't implement ioctl(), which is pretty
3192strange for a machine that supports C.
3193
c289d2f7
JH
3194=item ioctl() on unopened %s
3195
3196(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 3197Check your control flow and number of arguments.
c289d2f7 3198
fe13d51d 3199=item IO layers (like '%s') unavailable
363c40c4
SB
3200
3201(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 3202you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
3203with 'useperlio'.
3204
80cbd5ad
JH
3205=item IO::Socket::atmark not implemented on this architecture
3206
3207(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 3208neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 3209
6e8a73f2 3210=item '%s' is an unknown bound type in regex; marked by S<<-- HERE> in m/%s/
64935bc6
KW
3211
3212(F) You used C<\b{...}> or C<\B{...}> and the C<...> is not known to
3213Perl. The current valid ones are given in
3214L<perlrebackslash/\b{}, \b, \B{}, \B>.
3215
1ed4b776 3216=item %s() isn't allowed on :utf8 handles
74d1b2e4 3217
1ed4b776
TC
3218(F) The sysread(), recv(), syswrite() and send() operators are
3219not allowed on handles that have the C<:utf8> layer, either explicitly, or
74d1b2e4
FC
3220implicitly, eg., with the C<:encoding(UTF-16LE)> layer.
3221
1ed4b776
TC
3222Previously sysread() and recv() currently use only the C<:utf8> flag for the stream,
3223ignoring the actual layers. Since sysread() and recv() did no UTF-8
74d1b2e4
FC
3224validation they can end up creating invalidly encoded scalars.
3225
1ed4b776
TC
3226Similarly, syswrite() and send() used only the C<:utf8> flag, otherwise ignoring
3227any layers. If the flag is set, both wrote the value UTF-8 encoded, even if
74d1b2e4
FC
3228the layer is some different encoding, such as the example above.
3229
3230Ideally, all of these operators would completely ignore the C<:utf8> state,
3231working only with bytes, but this would result in silently breaking existing
1972ac5c
A
3232code.
3233
d4360efa 3234=item "%s" is more clearly written simply as "%s" in regex; marked by S<<-- HERE> in m/%s/
acdfc3b6 3235
d4360efa 3236(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
30b17cc1 3237
3f673807
FC
3238You specified a character that has the given plainer way of writing it, and
3239which is also portable to platforms running with different character sets.
acdfc3b6 3240
dcb414ac 3241=item $* is no longer supported as of Perl 5.30
a678626e 3242
dcb414ac
JK
3243(F) The special variable C<$*>, deprecated in older perls, was removed in
32445.10.0, is no longer supported and is a fatal error as of Perl 5.30. In
a678626e
A
3245previous versions of perl the use of C<$*> enabled or disabled multi-line
3246matching within a string.
3247
3248Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
3249modifiers. You can enable C</m> for a lexical scope (even a whole file)
3250with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
3251then all regular expressions behaved as if they were written using C</m>.)
3252
37398dc1
A
3253Use of this variable will be a fatal error in Perl 5.30.
3254
dcb414ac 3255=item $# is no longer supported as of Perl 5.30
a678626e 3256
dcb414ac
JK
3257(F) The special variable C<$#>, deprecated in older perls, was removed as of
32585.10.0, is no longer supported and is a fatal error as of Perl 5.30. You
a678626e
A
3259should use the printf/sprintf functions instead.
3260
ccf3535a 3261=item '%s' is not a code reference
6ad11d81 3262
6903afa2
FC
3263(W overload) The second (fourth, sixth, ...) argument of
3264overload::constant needs to be a code reference. Either
3265an anonymous subroutine, or a reference to a subroutine.
6ad11d81 3266
ccf3535a 3267=item '%s' is not an overloadable type
6ad11d81 3268
04a80ee0
RGS
3269(W overload) You tried to overload a constant type the overload package is
3270unaware of.
6ad11d81 3271
5a25739d
FC
3272=item -i used with no filenames on the command line, reading from STDIN
3273
3274(S inplace) The C<-i> option was passed on the command line, indicating
3275that the script is intended to edit files in place, but no files were
3276given. This is usually a mistake, since editing STDIN in place doesn't
3277make sense, and can be confusing because it can make perl look like
3278it is hanging when it is really just trying to read from STDIN. You
3279should either pass a filename to edit, or remove C<-i> from the command
3280line. See L<perlrun> for more details.
3281
aec0ef10 3282=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
3283
3284(P) The regular expression parser is confused.
3285
3286=item Label not found for "last %s"
3287
be771a83
GS
3288(F) You named a loop to break out of, but you're not currently in a loop
3289of that name, not even if you count where you were called from. See
3290L<perlfunc/last>.
a0d0e21e
LW
3291
3292=item Label not found for "next %s"
3293
3294(F) You named a loop to continue, but you're not currently in a loop of
3295that name, not even if you count where you were called from. See
3296L<perlfunc/last>.
3297
3298=item Label not found for "redo %s"
3299
3300(F) You named a loop to restart, but you're not currently in a loop of
3301that name, not even if you count where you were called from. See
3302L<perlfunc/last>.
3303
85ab1d1d 3304=item leaving effective %s failed
5ff3f7a4 3305
85ab1d1d 3306(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
3307effective uids or gids failed.
3308
49704364
LW
3309=item length/code after end of string in unpack
3310
d7f8936a 3311(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
3312length/code combination tried to obtain more data. This results in
3313an undefined value for the length. See L<perlfunc/pack>.
49704364 3314
25e26107 3315=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 3316
0d46a4e7
FC
3317(W syntax) You used length() on either an array or a hash when you
3318probably wanted a count of the items.
e508c8a4
MH
3319
3320Array size can be obtained by doing:
3321
3322 scalar(@array);
3323
3324The number of items in a hash can be obtained by doing:
3325
3326 scalar(keys %hash);
3327
f0e67a1d
Z
3328=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
3329
d4fe7078
RS
3330(F) An extension is attempting to insert text into the current parse
3331(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
3332couldn't be part of the current input. This is an inherent pitfall
3333of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 3334it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
3335
3336=item Lexing code internal error (%s)
3337
3338(F) Lexing code supplied by an extension violated the lexer's API in a
3339detectable way.
3340
69282e91 3341=item listen() on closed socket %s
a0d0e21e 3342
be771a83
GS
3343(W closed) You tried to do a listen on a closed socket. Did you forget
3344to check the return value of your socket() call? See
3345L<perlfunc/listen>.
a0d0e21e 3346
6651ba0b
FC
3347=item List form of piped open not implemented
3348
3349(F) On some platforms, notably Windows, the three-or-more-arguments
3350form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
3351Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
3352
2a6971a9
KW
3353=item Literal vertical space in [] is illegal except under /x in regex;
3354marked by S<<-- HERE> in m/%s/
3355
3356(F) (only under C<S<use re 'strict'>> or within C<(?[...])>)
3357
3358Likely you forgot the C</x> modifier or there was a typo in the pattern.
3359For example, did you really mean to match a form-feed? If so, all the
3360ASCII vertical space control characters are representable by escape
3361sequences which won't present such a jarring appearance as your pattern
3362does when displayed.
3363
3364 \r carriage return
3365 \f form feed
3366 \n line feed
3367 \cK vertical tab
3368
dc6bb7ba
FC
3369=item %s: loadable library and perl binaries are mismatched (got handshake key %p, needed %p)
3370
3371(P) A dynamic loading library C<.so> or C<.dll> was being loaded into the
3372process that was built against a different build of perl than the
3373said library was compiled against. Reinstalling the XS module will
3374likely fix this error.
3375
8b7358b9 3376=item Locale '%s' contains (at least) the following characters which
f03e1e3a 3377have unexpected meanings: %s The Perl program will use the expected
8b7358b9
KW
3378meanings
3379
3380(W locale) You are using the named UTF-8 locale. UTF-8 locales are
578a6a87
KW
3381expected to have very particular behavior, which most do. This message
3382arises when perl found some departures from the expectations, and is
3383notifying you that the expected behavior overrides these differences.
3384In some cases the differences are caused by the locale definition being
3385defective, but the most common causes of this warning are when there are
3386ambiguities and conflicts in following the Standard, and the locale has
3387chosen an approach that differs from Perl's.
3388
3389One of these is because that, contrary to the claims, Unicode is not
a2d13ee0
FC
3390completely locale insensitive. Turkish and some related languages
3391have two types of C<"I"> characters. One is dotted in both upper- and
578a6a87