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1=head1 NAME
2
3perldiag - various Perl diagnostics
4
5=head1 DESCRIPTION
6
7These messages are classified as follows (listed in increasing order of
8desperation):
9
10 (W) A warning (optional).
d1d15184 11 (D) A deprecation (enabled by default).
00eb3f2b 12 (S) A severe warning (enabled by default).
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13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
54310121 15 (X) A very fatal error (nontrappable).
cb1a09d0 16 (A) An alien error message (not generated by Perl).
a0d0e21e 17
75b44862 18The majority of messages from the first three classifications above
64977eb6 19(W, D & S) can be controlled using the C<warnings> pragma.
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20
21If a message can be controlled by the C<warnings> pragma, its warning
22category is included with the classification letter in the description
466416ed 23below. E.g. C<(W closed)> means a warning in the C<closed> category.
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24
25Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
fa816bf3 26and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
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27to a reference to a routine that will be called on each warning instead
28of printing it. See L<perlvar>.
29
b7eceb5b 30Severe warnings are always enabled, unless they are explicitly disabled
e476b1b5 31with the C<warnings> pragma or the B<-X> switch.
4438c4b7 32
748a9306 33Trappable errors may be trapped using the eval operator. See
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34L<perlfunc/eval>. In almost all cases, warnings may be selectively
35disabled or promoted to fatal errors using the C<warnings> pragma.
36See L<warnings>.
a0d0e21e 37
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38The messages are in alphabetical order, without regard to upper or
39lower-case. Some of these messages are generic. Spots that vary are
40denoted with a %s or other printf-style escape. These escapes are
41ignored by the alphabetical order, as are all characters other than
42letters. To look up your message, just ignore anything that is not a
43letter.
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44
45=over 4
46
6df41af2 47=item accept() on closed socket %s
33633739 48
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49(W closed) You tried to do an accept on a closed socket. Did you forget
50to check the return value of your socket() call? See
51L<perlfunc/accept>.
33633739 52
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53=item Aliasing via reference is experimental
54
55(S experimental::refaliasing) This warning is emitted if you use
56a reference constructor on the left-hand side of an assignment to
57alias one variable to another. Simply suppress the warning if you
58want to use the feature, but know that in doing so you are taking
59the risk of using an experimental feature which may change or be
60removed in a future Perl version:
61
62 no warnings "experimental::refaliasing";
63 use feature "refaliasing";
64 \$x = \$y;
65
de42a5a9 66=item Allocation too large: %x
a0d0e21e 67
6df41af2 68(X) You can't allocate more than 64K on an MS-DOS machine.
a0d0e21e 69
04f74579 70=item '%c' allowed only after types %s in %s
ef54e1a4 71
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72(F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
73after certain types. See L<perlfunc/pack>.
ef54e1a4 74
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75=item alpha->numify() is lossy
76
77(W numeric) An alpha version can not be numified without losing
78information.
79
6df41af2 80=item Ambiguous call resolved as CORE::%s(), qualify as such or use &
43192e07 81
75b44862 82(W ambiguous) A subroutine you have declared has the same name as a Perl
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83keyword, and you have used the name without qualification for calling
84one or the other. Perl decided to call the builtin because the
85subroutine is not imported.
43192e07 86
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87To force interpretation as a subroutine call, either put an ampersand
88before the subroutine name, or qualify the name with its package.
89Alternatively, you can import the subroutine (or pretend that it's
90imported with the C<use subs> pragma).
43192e07 91
6df41af2 92To silently interpret it as the Perl operator, use the C<CORE::> prefix
496a33f5 93on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
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94to be an object method (see L<perlsub/"Subroutine Attributes"> or
95L<attributes>).
43192e07 96
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97=item Ambiguous range in transliteration operator
98
99(F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
100all. To include a C<-> character in a transliteration, put it either
101first or last. (In the past, C<tr/a-z-0//> was synonymous with
102C<tr/a-y//>, which was probably not what you would have expected.)
103
6df41af2 104=item Ambiguous use of %s resolved as %s
43192e07 105
7c7af292 106(S ambiguous) You said something that may not be interpreted the way
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107you thought. Normally it's pretty easy to disambiguate it by supplying
108a missing quote, operator, parenthesis pair or declaration.
a0d0e21e 109
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110=item Ambiguous use of -%s resolved as -&%s()
111
112(S ambiguous) You wrote something like C<-foo>, which might be the
113string C<"-foo">, or a call to the function C<foo>, negated. If you meant
114the string, just write C<"-foo">. If you meant the function call,
115write C<-foo()>.
116
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117=item Ambiguous use of %c resolved as operator %c
118
7c7af292 119(S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
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120bitwise and, and multiplication) I<and> initial special characters
121(denoting hashes, subroutines and typeglobs), and you said something
122like C<*foo * foo> that might be interpreted as either of them. We
123assumed you meant the infix operator, but please try to make it more
124clear -- in the example given, you might write C<*foo * foo()> if you
125really meant to multiply a glob by the result of calling a function.
d8225693 126
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127=item Ambiguous use of %c{%s} resolved to %c%s
128
129(W ambiguous) You wrote something like C<@{foo}>, which might be
130asking for the variable C<@foo>, or it might be calling a function
131named foo, and dereferencing it as an array reference. If you wanted
1cecf2c0 132the variable, you can just write C<@foo>. If you wanted to call the
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133function, write C<@{foo()}> ... or you could just not have a variable
134and a function with the same name, and save yourself a lot of trouble.
135
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136=item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
137
138=item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
4da60377 139
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140(W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
141the name of a Perl keyword), which might be looking for element number
1422 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
143might have meant to pass an anonymous arrayref to the function named
144foo, and then do a scalar deref on the value it returns. If you meant
145that, write C<${foo([2])}>.
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146
147In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
148to disambiguate between array subscripts and character classes.
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149C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
150by the character class C<[2345]>. If an array subscript is what you
151want, you can avoid the warning by changing C</${length[2345]}/> to the
152unsightly C</${\$length[2345]}/>, by renaming your array to something
153that does not coincide with a built-in keyword, or by simply turning
154off warnings with C<no warnings 'ambiguous';>.
4da60377 155
6df41af2 156=item '|' and '<' may not both be specified on command line
a0d0e21e 157
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158(F) An error peculiar to VMS. Perl does its own command line
159redirection, and found that STDIN was a pipe, and that you also tried to
160redirect STDIN using '<'. Only one STDIN stream to a customer, please.
c9f97d15 161
6df41af2 162=item '|' and '>' may not both be specified on command line
1028017a 163
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164(F) An error peculiar to VMS. Perl does its own command line
165redirection, and thinks you tried to redirect stdout both to a file and
166into a pipe to another command. You need to choose one or the other,
167though nothing's stopping you from piping into a program or Perl script
168which 'splits' output into two streams, such as
1028017a 169
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170 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
171 while (<STDIN>) {
172 print;
173 print OUT;
174 }
175 close OUT;
c9f97d15 176
6df41af2 177=item Applying %s to %s will act on scalar(%s)
eb6e2d6f 178
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179(W misc) The pattern match (C<//>), substitution (C<s///>), and
180transliteration (C<tr///>) operators work on scalar values. If you apply
be771a83 181one of them to an array or a hash, it will convert the array or hash to
ac036724 182a scalar value (the length of an array, or the population info of a
183hash) and then work on that scalar value. This is probably not what
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184you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
185alternatives.
eb6e2d6f 186
6df41af2 187=item Arg too short for msgsnd
76cd736e 188
6df41af2 189(F) msgsnd() requires a string at least as long as sizeof(long).
76cd736e 190
f86702cc 191=item Argument "%s" isn't numeric%s
a0d0e21e 192
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193(W numeric) The indicated string was fed as an argument to an operator
194that expected a numeric value instead. If you're fortunate the message
195will identify which operator was so unfortunate.
a0d0e21e 196
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197Note that for the C<Inf> and C<NaN> (infinity and not-a-number) the
198definition of "numeric" is somewhat unusual: the strings themselves
199(like "Inf") are considered numeric, and anything following them is
200considered non-numeric.
201
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202=item Argument list not closed for PerlIO layer "%s"
203
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204(W layer) When pushing a layer with arguments onto the Perl I/O
205system you forgot the ) that closes the argument list. (Layers
206take care of transforming data between external and internal
207representations.) Perl stopped parsing the layer list at this
208point and did not attempt to push this layer. If your program
209didn't explicitly request the failing operation, it may be the
210result of the value of the environment variable PERLIO.
b4581f09 211
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212=item Argument "%s" treated as 0 in increment (++)
213
214(W numeric) The indicated string was fed as an argument to the C<++>
215operator which expects either a number or a string matching
216C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
217Auto-decrement> for details.
218
637494ac 219=item Array passed to stat will be coerced to a scalar%s
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220
221(W syntax) You called stat() on an array, but the array will be
222coerced to a scalar - the number of elements in the array.
223
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224=item A signature parameter must start with '$', '@' or '%'
225
226(F) Each subroutine signature parameter declaration must start with a valid
227sigil; for example:
228
229 sub foo ($a, $, $b = 1, @c) {}
230
231=item A slurpy parameter may not have a default value
232
233(F) Only scalar subroutine signature parameters may have a default value;
234for example:
235
236 sub foo ($a = 1) {} # legal
237 sub foo (@a = (1)) {} # invalid
238 sub foo (%a = (a => b)) {} # invalid
239
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240=item assertion botched: %s
241
21b5e840 242(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 243
0eacef8e 244=item Assertion %s failed: file "%s", line %d
a0d0e21e 245
21b5e840 246(X) A general assertion failed. The file in question must be examined.
a0d0e21e 247
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248=item Assigned value is not a reference
249
250(F) You tried to assign something that was not a reference to an lvalue
251reference (e.g., C<\$x = $y>). If you meant to make $x an alias to $y, use
252C<\$x = \$y>.
253
254=item Assigned value is not %s reference
255
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256(F) You tried to assign a reference to a reference constructor, but the
257two references were not of the same type. You cannot alias a scalar to
258an array, or an array to a hash; the two types must match.
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259
260 \$x = \@y; # error
261 \@x = \%y; # error
262 $y = [];
263 \$x = $y; # error; did you mean \$y?
264
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265=item Assigning non-zero to $[ is no longer possible
266
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267(F) When the "array_base" feature is disabled
268(e.g., and under C<use v5.16;>, and as of Perl 5.30)
7d345e3d 269the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 270
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271=item Assignment to both a list and a scalar
272
273(F) If you assign to a conditional operator, the 2nd and 3rd arguments
274must either both be scalars or both be lists. Otherwise Perl won't
275know which context to supply to the right side.
276
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277=item Assuming NOT a POSIX class since %s in regex; marked by S<<-- HERE> in m/%s/
278
279(W regexp) You had something like these:
280
281 [[:alnum]]
282 [[:digit:xyz]
283
284They look like they might have been meant to be the POSIX classes
285C<[:alnum:]> or C<[:digit:]>. If so, they should be written:
286
287 [[:alnum:]]
288 [[:digit:]xyz]
289
290Since these aren't legal POSIX class specifications, but are legal
291bracketed character classes, Perl treats them as the latter. In the
292first example, it matches the characters C<":">, C<"[">, C<"a">, C<"l">,
293C<"m">, C<"n">, and C<"u">.
294
295If these weren't meant to be POSIX classes, this warning message is
296spurious, and can be suppressed by reordering things, such as
297
298 [[al:num]]
299
300or
301
302 [[:munla]]
303
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304=item <> at require-statement should be quotes
305
306(F) You wrote C<< require <file> >> when you should have written
307C<require 'file'>.
308
2393f1b9 309=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 310
49293501 311(F) The failing code has attempted to get or set a key which is not in
2393f1b9 312the current set of allowed keys of a restricted hash.
49293501 313
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314=item Attempt to bless into a freed package
315
316(F) You wrote C<bless $foo> with one argument after somehow causing
317the current package to be freed. Perl cannot figure out what to
0c5a5b27 318do, so it throws up its hands in despair.
dcdfe746 319
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320=item Attempt to bless into a reference
321
322(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 323the name of the package to bless the resulting object into. You've
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324supplied instead a reference to something: perhaps you wrote
325
326 bless $self, $proto;
327
328when you intended
329
330 bless $self, ref($proto) || $proto;
331
332If you actually want to bless into the stringified version
333of the reference supplied, you need to stringify it yourself, for
334example by:
335
336 bless $self, "$proto";
337
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338=item Attempt to clear deleted array
339
340(S debugging) An array was assigned to when it was being freed.
341Freed values are not supposed to be visible to Perl code. This
342can also happen if XS code calls C<av_clear> from a custom magic
343callback on the array.
344
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345=item Attempt to delete disallowed key '%s' from a restricted hash
346
347(F) The failing code attempted to delete from a restricted hash a key
348which is not in its key set.
349
350=item Attempt to delete readonly key '%s' from a restricted hash
351
352(F) The failing code attempted to delete a key whose value has been
353declared readonly from a restricted hash.
354
de42a5a9 355=item Attempt to free non-arena SV: 0x%x
a0d0e21e 356
f84fe999 357(S internal) All SV objects are supposed to be allocated from arenas
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358that will be garbage collected on exit. An SV was discovered to be
359outside any of those arenas.
a0d0e21e 360
12578ffb 361=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 362
f84fe999 363(S internal) Perl maintains a reference-counted internal table of
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364strings to optimize the storage and access of hash keys and other
365strings. This indicates someone tried to decrement the reference count
366of a string that can no longer be found in the table.
bbce6d69 367
7d5b40b4 368=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 369
f84fe999 370(S debugging) Mortalized values are supposed to be freed by the
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371free_tmps() routine. This indicates that something else is freeing the
372SV before the free_tmps() routine gets a chance, which means that the
373free_tmps() routine will be freeing an unreferenced scalar when it does
374try to free it.
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375
376=item Attempt to free unreferenced glob pointers
377
f84fe999 378(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 379
7d5b40b4 380=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 381
8f7e4d2c 382(S internal) Perl went to decrement the reference count of a scalar to
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383see if it would go to 0, and discovered that it had already gone to 0
384earlier, and should have been freed, and in fact, probably was freed.
385This could indicate that SvREFCNT_dec() was called too many times, or
386that SvREFCNT_inc() was called too few times, or that the SV was
387mortalized when it shouldn't have been, or that memory has been
388corrupted.
a0d0e21e 389
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390=item Attempt to pack pointer to temporary value
391
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392(W pack) You tried to pass a temporary value (like the result of a
393function, or a computed expression) to the "p" pack() template. This
394means the result contains a pointer to a location that could become
395invalid anytime, even before the end of the current statement. Use
396literals or global values as arguments to the "p" pack() template to
397avoid this warning.
84902520 398
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399=item Attempt to reload %s aborted.
400
401(F) You tried to load a file with C<use> or C<require> that failed to
402compile once already. Perl will not try to compile this file again
403unless you delete its entry from %INC. See L<perlfunc/require> and
404L<perlvar/%INC>.
405
1b20cd17
NC
406=item Attempt to set length of freed array
407
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FC
408(W misc) You tried to set the length of an array which has
409been freed. You can do this by storing a reference to the
410scalar representing the last index of an array and later
411assigning through that reference. For example
1b20cd17
NC
412
413 $r = do {my @a; \$#a};
414 $$r = 503
415
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416=item Attempt to use reference as lvalue in substr
417
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418(W substr) You supplied a reference as the first argument to substr()
419used as an lvalue, which is pretty strange. Perhaps you forgot to
420dereference it first. See L<perlfunc/substr>.
b7a902f4 421
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422=item Attribute prototype(%s) discards earlier prototype attribute in same sub
423
424(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
425example. Since each sub can only have one prototype, the earlier
426declaration(s) are discarded while the last one is applied.
427
ccce04a4
FC
428=item av_reify called on tied array
429
430(S debugging) This indicates that something went wrong and Perl got I<very>
431confused about C<@_> or C<@DB::args> being tied.
432
de42a5a9 433=item Bad arg length for %s, is %u, should be %d
a0d0e21e 434
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435(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
436or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 437S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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438S<sizeof(struct shmid_ds *)>.
439
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440=item Bad evalled substitution pattern
441
496a33f5 442(F) You've used the C</e> switch to evaluate the replacement for a
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443substitution, but perl found a syntax error in the code to evaluate,
444most likely an unexpected right brace '}'.
445
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446=item Bad filehandle: %s
447
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448(F) A symbol was passed to something wanting a filehandle, but the
449symbol has no filehandle associated with it. Perhaps you didn't do an
450open(), or did it in another package.
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451
452=item Bad free() ignored
453
be771a83 454(S malloc) An internal routine called free() on something that had never
fa816bf3 455been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 456setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 457
9ea8bc6d 458This message can be seen quite often with DB_File on systems with "hard"
6903afa2 459dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 460which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 461
aa689395
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462=item Bad hash
463
464(P) One of the internal hash routines was passed a null HV pointer.
465
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466=item Badly placed ()'s
467
468(A) You've accidentally run your script through B<csh> instead
469of Perl. Check the #! line, or manually feed your script into
470Perl yourself.
471
a7cb8dae 472=item Bad name after %s
a0d0e21e 473
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474(F) You started to name a symbol by using a package prefix, and then
475didn't finish the symbol. In particular, you can't interpolate outside
476of quotes, so
a0d0e21e
LW
477
478 $var = 'myvar';
479 $sym = mypack::$var;
480
481is not the same as
482
483 $var = 'myvar';
484 $sym = "mypack::$var";
485
88e1f1a2
JV
486=item Bad plugin affecting keyword '%s'
487
488(F) An extension using the keyword plugin mechanism violated the
489plugin API.
490
4ad56ec9
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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
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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
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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
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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
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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
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522=item Bareword found in conditional
523
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524(W bareword) The compiler found a bareword where it expected a
525conditional, which often indicates that an || or && was parsed as part
526of the last argument of the previous construct, for example:
34d09196
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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
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532
533 use constant TYPO => 1;
534 if (TYOP) { print "foo" }
535
536The C<strict> pragma is useful in avoiding such errors.
537
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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
0f2beabb
TC
566=item Bareword filehandle "%s" not allowed under 'no feature "bareword_filehandles"'
567
568(F) You attempted to use a bareword filehandle with the
569C<bareword_filehandles> feature disabled.
570
571Only the built-in handles C<STDIN>, C<STDOUT>, C<STDERR>, C<ARGV>,
572C<ARGVOUT> and C<DATA> can be used with the C<bareword_filehandles>
573feature disabled.
574
a0d0e21e
LW
575=item BEGIN failed--compilation aborted
576
be771a83
GS
577(F) An untrapped exception was raised while executing a BEGIN
578subroutine. Compilation stops immediately and the interpreter is
579exited.
a0d0e21e 580
68dc0745
PP
581=item BEGIN not safe after errors--compilation aborted
582
583(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
be771a83
GS
584implies a C<BEGIN {}>) after one or more compilation errors had already
585occurred. Since the intended environment for the C<BEGIN {}> could not
586be guaranteed (due to the errors), and since subsequent code likely
587depends on its correct operation, Perl just gave up.
68dc0745 588
c782d7ee 589=item \%d better written as $%d
6df41af2 590
be771a83
GS
591(W syntax) Outside of patterns, backreferences live on as variables.
592The use of backslashes is grandfathered on the right-hand side of a
593substitution, but stylistically it's better to use the variable form
594because other Perl programmers will expect it, and it works better if
595there are more than 9 backreferences.
6df41af2 596
252aa082
JH
597=item Binary number > 0b11111111111111111111111111111111 non-portable
598
e476b1b5 599(W portable) The binary number you specified is larger than 2**32-1
9e24b6e2
JH
600(4294967295) and therefore non-portable between systems. See
601L<perlport> for more on portability concerns.
252aa082 602
69282e91 603=item bind() on closed socket %s
a0d0e21e 604
be771a83
GS
605(W closed) You tried to do a bind on a closed socket. Did you forget to
606check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 607
c289d2f7
JH
608=item binmode() on closed filehandle %s
609
610(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 611Check your control flow and number of arguments.
c289d2f7 612
c5a0f51a
JH
613=item Bit vector size > 32 non-portable
614
e476b1b5 615(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 616
043c750c 617=item Bizarre copy of %s
4633a7c4 618
be771a83 619(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 620copiable.
4633a7c4 621
5a25739d
FC
622=item Bizarre SvTYPE [%d]
623
434f489b 624(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
625encountered an invalid data type.
626
b927b7e9 627=item Both or neither range ends should be Unicode in regex; marked by
6e8a73f2 628S<<-- HERE> in m/%s/
b927b7e9
KW
629
630(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
631
632In a bracketed character class in a regular expression pattern, you
633had a range which has exactly one end of it specified using C<\N{}>, and
634the other end is specified using a non-portable mechanism. Perl treats
635the range as a Unicode range, that is, all the characters in it are
636considered to be the Unicode characters, and which may be different code
637points on some platforms Perl runs on. For example, C<[\N{U+06}-\x08]>
638is treated as if you had instead said C<[\N{U+06}-\N{U+08}]>, that is it
639matches the characters whose code points in Unicode are 6, 7, and 8.
640But that C<\x08> might indicate that you meant something different, so
641the warning gets raised.
642
f675dbe5
CB
643=item Buffer overflow in prime_env_iter: %s
644
be771a83
GS
645(W internal) A warning peculiar to VMS. While Perl was preparing to
646iterate over %ENV, it encountered a logical name or symbol definition
647which was too long, so it was truncated to the string shown.
f675dbe5 648
a0d0e21e
LW
649=item Callback called exit
650
4929bf7b 651(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
652exited by calling exit.
653
6df41af2 654=item %s() called too early to check prototype
f675dbe5 655
be771a83
GS
656(W prototype) You've called a function that has a prototype before the
657parser saw a definition or declaration for it, and Perl could not check
658that the call conforms to the prototype. You need to either add an
659early prototype declaration for the subroutine in question, or move the
660subroutine definition ahead of the call to get proper prototype
661checking. Alternatively, if you are certain that you're calling the
662function correctly, you may put an ampersand before the name to avoid
663the warning. See L<perlsub>.
f675dbe5 664
0c7df902
JH
665=item Cannot chr %f
666
667(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
668
1b4d0d79
TC
669=item Cannot complete in-place edit of %s: %s
670
671(F) Your perl script appears to have changed directory while
672performing an in-place edit of a file specified by a relative path,
673and your system doesn't include the directory relative POSIX functions
674needed to handle that.
675
5dee29d4 676=item Cannot compress %f in pack
0c7df902 677
5dee29d4
JH
678(F) You tried compressing an infinity or not-a-number as an unsigned
679integer with BER, which makes no sense.
0c7df902 680
49704364 681=item Cannot compress integer in pack
0258719b 682
717feafc
JH
683(F) An argument to pack("w",...) was too large to compress.
684The BER compressed integer format can only be used with positive
685integers, and you attempted to compress a very large number (> 1e308).
686See L<perlfunc/pack>.
0258719b 687
49704364 688=item Cannot compress negative numbers in pack
0258719b
NC
689
690(F) An argument to pack("w",...) was negative. The BER compressed integer
691format can only be used with positive integers. See L<perlfunc/pack>.
692
5c1f4d79
NC
693=item Cannot convert a reference to %s to typeglob
694
6903afa2
FC
695(F) You manipulated Perl's symbol table directly, stored a reference
696in it, then tried to access that symbol via conventional Perl syntax.
697The access triggers Perl to autovivify that typeglob, but it there is
698no legal conversion from that type of reference to a typeglob.
5c1f4d79 699
4040665a 700=item Cannot copy to %s
ba2fdce6
NC
701
702(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 703be directly assigned to.
ba2fdce6 704
b5d97229
RGS
705=item Cannot find encoding "%s"
706
707(S io) You tried to apply an encoding that did not exist to a filehandle,
708either with open() or binmode().
709
714f94d1
FC
710=item Cannot open %s as a dirhandle: it is already open as a filehandle
711
712(F) You tried to use opendir() to associate a dirhandle to a symbol (glob
713or scalar) that already holds a filehandle. Since this idiom might render
714your code confusing, it was deprecated in Perl 5.10. As of Perl 5.28, it
715is a fatal error.
716
717=item Cannot open %s as a filehandle: it is already open as a dirhandle
718
719(F) You tried to use open() to associate a filehandle to a symbol (glob
720or scalar) that already holds a dirhandle. Since this idiom might render
721your code confusing, it was deprecated in Perl 5.10. As of Perl 5.28, it
722is a fatal error.
723
0c7df902
JH
724=item Cannot pack %f with '%c'
725
5dee29d4 726(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
727which makes no sense.
728
729=item Cannot printf %f with '%c'
730
731(F) You tried printing an infinity or not-a-number as a character (%c),
732which makes no sense. Maybe you meant '%s', or just stringifying it?
733
7355df7e
FC
734=item Cannot set tied @DB::args
735
736(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
737is not supported. (Before this error was added, it used to crash.)
738
ce65bc73
FC
739=item Cannot tie unreifiable array
740
741(P) You somehow managed to call C<tie> on an array that does not
742keep a reference count on its arguments and cannot be made to
743do so. Such arrays are not even supposed to be accessible to
744Perl code, but are only used internally.
745
26b0dc0c 746=item Cannot yet reorder sv_vcatpvfn() arguments from va_list
46e58bd2 747
26b0dc0c 748(F) Some XS code tried to use C<sv_vcatpvfn()> or a related function with a
46e58bd2 749format string that specifies explicit indexes for some of the elements, and
d4e5761f
FC
750using a C-style variable-argument list (a C<va_list>). This is not currently
751supported. XS authors wanting to do this must instead construct a C array
752of C<SV*> scalars containing the arguments.
46e58bd2 753
96ebfdd7
RK
754=item Can only compress unsigned integers in pack
755
756(F) An argument to pack("w",...) was not an integer. The BER compressed
757integer format can only be used with positive integers, and you attempted
758to compress something else. See L<perlfunc/pack>.
759
a0d0e21e
LW
760=item Can't bless non-reference value
761
762(F) Only hard references may be blessed. This is how Perl "enforces"
763encapsulation of objects. See L<perlobj>.
764
7896dde7
Z
765=item Can't "break" in a loop topicalizer
766
767(F) You called C<break>, but you're in a C<foreach> block rather than
768a C<given> block. You probably meant to use C<next> or C<last>.
769
770=item Can't "break" outside a given block
771
772(F) You called C<break>, but you're not inside a C<given> block.
773
6df41af2
GS
774=item Can't call method "%s" on an undefined value
775
776(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
777object reference or package name contains an undefined value. Something
778like this will reproduce the error:
6df41af2
GS
779
780 $BADREF = undef;
781 process $BADREF 1,2,3;
782 $BADREF->process(1,2,3);
783
a0d0e21e
LW
784=item Can't call method "%s" on unblessed reference
785
54310121 786(F) A method call must know in what package it's supposed to run. It
be771a83
GS
787ordinarily finds this out from the object reference you supply, but you
788didn't supply an object reference in this case. A reference isn't an
789object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
790
791=item Can't call method "%s" without a package or object reference
792
793(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
794object reference or package name contains an expression that returns a
795defined value which is neither an object reference nor a package name.
72b5445b
GS
796Something like this will reproduce the error:
797
798 $BADREF = 42;
799 process $BADREF 1,2,3;
800 $BADREF->process(1,2,3);
801
dfe378f1
FC
802=item Can't call mro_isa_changed_in() on anonymous symbol table
803
804(P) Perl got confused as to whether a hash was a plain hash or a
805symbol table hash when trying to update @ISA caches.
806
2bf7e7b2
FC
807=item Can't call mro_method_changed_in() on anonymous symbol table
808
809(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
810not attached to the symbol table.
811
a0d0e21e
LW
812=item Can't chdir to %s
813
f703fc96 814(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
815that you can chdir to, possibly because it doesn't exist.
816
0545a864 817=item Can't check filesystem of script "%s" for nosuid
104d25b7 818
be771a83
GS
819(P) For some reason you can't check the filesystem of the script for
820nosuid.
104d25b7 821
22e74366 822=item Can't coerce %s to %s in %s
a0d0e21e
LW
823
824(F) Certain types of SVs, in particular real symbol table entries
55497cff 825(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
826say things like:
827
828 *foo += 1;
829
830You CAN say
831
832 $foo = *foo;
833 $foo += 1;
834
835but then $foo no longer contains a glob.
836
7896dde7 837=item Can't "continue" outside a when block
dc57907a 838
7896dde7
Z
839(F) You called C<continue>, but you're not inside a C<when>
840or C<default> block.
0d863452 841
a0d0e21e
LW
842=item Can't create pipe mailbox
843
be771a83
GS
844(P) An error peculiar to VMS. The process is suffering from exhausted
845quotas or other plumbing problems.
a0d0e21e 846
eb64745e
GS
847=item Can't declare %s in "%s"
848
30c282f6
NC
849(F) Only scalar, array, and hash variables may be declared as "my", "our" or
850"state" variables. They must have ordinary identifiers as names.
a0d0e21e 851
7896dde7
Z
852=item Can't "default" outside a topicalizer
853
854(F) You have used a C<default> block that is neither inside a
855C<foreach> loop nor a C<given> block. (Note that this error is
856issued on exit from the C<default> block, so you won't get the
857error if you use an explicit C<continue>.)
858
1e85b658
DM
859=item Can't determine class of operator %s, assuming BASEOP
860
861(S) This warning indicates something wrong in the internals of perl.
862Perl was trying to find the class (e.g. LISTOP) of a particular OP,
863and was unable to do so. This is likely to be due to a bug in the perl
864internals, or due to a bug in XS code which manipulates perl optrees.
865
a2162cd9
FC
866=item Can't do inplace edit: %s is not a regular file
867
868(S inplace) You tried to use the B<-i> switch on a special file, such as
869a file in /dev, a FIFO or an uneditable directory. The file was ignored.
870
871=item Can't do inplace edit on %s: %s
872
873(S inplace) The creation of the new file failed for the indicated
874reason.
875
a2162cd9
FC
876=item Can't do inplace edit: %s would not be unique
877
878(S inplace) Your filesystem does not support filenames longer than 14
879characters and Perl was unable to create a unique filename during
880inplace editing with the B<-i> switch. The file was ignored.
881
ab0b796c
KW
882=item Can't do %s("%s") on non-UTF-8 locale; resolved to "%s".
883
884(W locale) You are 1) running under "C<use locale>"; 2) the current
885locale is not a UTF-8 one; 3) you tried to do the designated case-change
886operation on the specified Unicode character; and 4) the result of this
887operation would mix Unicode and locale rules, which likely conflict.
888Mixing of different rule types is forbidden, so the operation was not
889done; instead the result is the indicated value, which is the best
890available that uses entirely Unicode rules. That turns out to almost
891always be the original character, unchanged.
892
893It is generally a bad idea to mix non-UTF-8 locales and Unicode, and
894this issue is one of the reasons why. This warning is raised when
895Unicode rules would normally cause the result of this operation to
896contain a character that is in the range specified by the locale,
8970..255, and hence is subject to the locale's rules, not Unicode's.
898
899If you are using locale purely for its characteristics related to things
900like its numeric and time formatting (and not C<LC_CTYPE>), consider
901using a restricted form of the locale pragma (see L<perllocale/The "use
902locale" pragma>) like "S<C<use locale ':not_characters'>>".
903
904Note that failed case-changing operations done as a result of
905case-insensitive C</i> regular expression matching will show up in this
906warning as having the C<fc> operation (as that is what the regular
907expression engine calls behind the scenes.)
908
a0d0e21e
LW
909=item Can't do waitpid with flags
910
be771a83
GS
911(F) This machine doesn't have either waitpid() or wait4(), so only
912waitpid() without flags is emulated.
a0d0e21e 913
a0d0e21e
LW
914=item Can't emulate -%s on #! line
915
be771a83
GS
916(F) The #! line specifies a switch that doesn't make sense at this
917point. For example, it'd be kind of silly to put a B<-x> on the #!
918line.
a0d0e21e 919
1109a392
MHM
920=item Can't %s %s-endian %ss on this platform
921
922(F) Your platform's byte-order is neither big-endian nor little-endian,
923or it has a very strange pointer size. Packing and unpacking big- or
924little-endian floating point values and pointers may not be possible.
925See L<perlfunc/pack>.
926
a0d0e21e
LW
927=item Can't exec "%s": %s
928
d1be9408 929(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
930named program for the indicated reason. Typical reasons include: the
931permissions were wrong on the file, the file wasn't found in
932C<$ENV{PATH}>, the executable in question was compiled for another
933architecture, or the #! line in a script points to an interpreter that
934can't be run for similar reasons. (Or maybe your system doesn't support
935#! at all.)
a0d0e21e
LW
936
937=item Can't exec %s
938
be771a83
GS
939(F) Perl was trying to execute the indicated program for you because
940that's what the #! line said. If that's not what you wanted, you may
941need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
942
943=item Can't execute %s
944
be771a83
GS
945(F) You used the B<-S> switch, but the copies of the script to execute
946found in the PATH did not have correct permissions.
2a92aaa0 947
6df41af2 948=item Can't find an opnumber for "%s"
2a92aaa0 949
be771a83
GS
950(F) A string of a form C<CORE::word> was given to prototype(), but there
951is no builtin with the name C<word>.
6df41af2
GS
952
953=item Can't find label %s
954
be771a83
GS
955(F) You said to goto a label that isn't mentioned anywhere that it's
956possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
957
958=item Can't find %s on PATH
959
be771a83
GS
960(F) You used the B<-S> switch, but the script to execute could not be
961found in the PATH.
a0d0e21e 962
6df41af2 963=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 964
be771a83
GS
965(F) You used the B<-S> switch, but the script to execute could not be
966found in the PATH, or at least not with the correct permissions. The
967script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
968
969=item Can't find string terminator %s anywhere before EOF
970
be771a83
GS
971(F) Perl strings can stretch over multiple lines. This message means
972that the closing delimiter was omitted. Because bracketed quotes count
973nesting levels, the following is missing its final parenthesis:
a0d0e21e 974
fb73857a
PP
975 print q(The character '(' starts a side comment.);
976
97b3d10f 977If you're getting this error from a here-document, you may have
b6b8cb97
FC
978included unseen whitespace before or after your closing tag or there
979may not be a linebreak after it. A good programmer's editor will have
980a way to help you find these characters (or lack of characters). See
981L<perlop> for the full details on here-documents.
a0d0e21e 982
660a4616
ST
983=item Can't find Unicode property definition "%s"
984
29f52644
KW
985=item Can't find Unicode property definition "%s" in regex; marked by <-- HERE in m/%s/
986
987(F) The named property which you specified via C<\p> or C<\P> is not one
988known to Perl. Perhaps you misspelled the name? See
e1b711da 989L<perluniprops/Properties accessible through \p{} and \P{}>
29f52644
KW
990for a complete list of available official
991properties. If it is a
992L<user-defined property|perlunicode/User-Defined Character Properties>
993it must have been defined by the time the regular expression is
994matched.
995
996If you didn't mean to use a Unicode property, escape the C<\p>, either
997by C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 998until C<\E>).
660a4616 999
b3647a36 1000=item Can't fork: %s
a0d0e21e 1001
be771a83
GS
1002(F) A fatal error occurred while trying to fork while opening a
1003pipeline.
a0d0e21e 1004
b3647a36
SR
1005=item Can't fork, trying again in 5 seconds
1006
c973c02e 1007(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
1008after five seconds.
1009
748a9306
LW
1010=item Can't get filespec - stale stat buffer?
1011
be771a83
GS
1012(S) A warning peculiar to VMS. This arises because of the difference
1013between access checks under VMS and under the Unix model Perl assumes.
1014Under VMS, access checks are done by filename, rather than by bits in
1015the stat buffer, so that ACLs and other protections can be taken into
1016account. Unfortunately, Perl assumes that the stat buffer contains all
1017the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 1018the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
1019the device name and FID present in the stat buffer, but this works only
1020if you haven't made a subsequent call to the CRTL stat() routine,
1021because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
1022appears, the name lookup failed, and the access-checking routine gave up
1023and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
1024routine knows about the Perl C<stat> operator and file tests, so you
1025shouldn't ever see this warning in response to a Perl command; it arises
1026only if some internal code takes stat buffers lightly.)
748a9306 1027
a0d0e21e
LW
1028=item Can't get pipe mailbox device name
1029
be771a83
GS
1030(P) An error peculiar to VMS. After creating a mailbox to act as a
1031pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
1032
1033=item Can't get SYSGEN parameter value for MAXBUF
1034
748a9306
LW
1035(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
1036mailbox buffers to be, and didn't get an answer.
a0d0e21e 1037
6d90e983
FC
1038=item Can't "goto" into a binary or list expression
1039
1040(F) A "goto" statement was executed to jump into the middle of a binary
1041or list expression. You can't get there from here. The reason for this
1042restriction is that the interpreter would get confused as to how many
1043arguments there are, resulting in stack corruption or crashes. This
1044error occurs in cases such as these:
1045
1046 goto F;
1047 print do { F: }; # Can't jump into the arguments to print
1048
1049 goto G;
1050 $x + do { G: $y }; # How is + supposed to get its first operand?
1051
a01f4640
FC
1052=item Can't "goto" into a "given" block
1053
1054(F) A "goto" statement was executed to jump into the middle of a C<given>
1055block. You can't get there from here. See L<perlfunc/goto>.
1056
6df41af2 1057=item Can't "goto" into the middle of a foreach loop
a0d0e21e 1058
be771a83
GS
1059(F) A "goto" statement was executed to jump into the middle of a foreach
1060loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
1061
1062=item Can't "goto" out of a pseudo block
1063
be771a83
GS
1064(F) A "goto" statement was executed to jump out of what might look like
1065a block, except that it isn't a proper block. This usually occurs if
1066you tried to jump out of a sort() block or subroutine, which is a no-no.
1067See L<perlfunc/goto>.
a0d0e21e 1068
5a25739d
FC
1069=item Can't goto subroutine from an eval-%s
1070
1071(F) The "goto subroutine" call can't be used to jump out of an eval
1072"string" or block.
1073
9850bf21 1074=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 1075
9850bf21
RH
1076(F) The "goto subroutine" call can't be used to jump out of the
1077comparison sub for a sort(), or from a similar callback (such
1078as the reduce() function in List::Util).
1079
6df41af2
GS
1080=item Can't goto subroutine outside a subroutine
1081
be771a83
GS
1082(F) The deeply magical "goto subroutine" call can only replace one
1083subroutine call for another. It can't manufacture one out of whole
1084cloth. In general you should be calling it out of only an AUTOLOAD
1085routine anyway. See L<perlfunc/goto>.
6df41af2 1086
0b5b802d
GS
1087=item Can't ignore signal CHLD, forcing to default
1088
be771a83
GS
1089(W signal) Perl has detected that it is being run with the SIGCHLD
1090signal (sometimes known as SIGCLD) disabled. Since disabling this
1091signal will interfere with proper determination of exit status of child
1092processes, Perl has reset the signal to its default value. This
1093situation typically indicates that the parent program under which Perl
1094may be running (e.g. cron) is being very careless.
0b5b802d 1095
e2c0f81f
DG
1096=item Can't kill a non-numeric process ID
1097
1098(F) Process identifiers must be (signed) integers. It is a fatal error to
1099attempt to kill() an undefined, empty-string or otherwise non-numeric
1100process identifier.
1101
6df41af2 1102=item Can't "last" outside a loop block
4633a7c4 1103
6df41af2 1104(F) A "last" statement was executed to break out of the current block,
be771a83
GS
1105except that there's this itty bitty problem called there isn't a current
1106block. Note that an "if" or "else" block doesn't count as a "loopish"
1107block, as doesn't a block given to sort(), map() or grep(). You can
1108usually double the curlies to get the same effect though, because the
1109inner curlies will be considered a block that loops once. See
1110L<perlfunc/last>.
4633a7c4 1111
2c7d6b9c
RGS
1112=item Can't linearize anonymous symbol table
1113
1114(F) Perl tried to calculate the method resolution order (MRO) of a
1115package, but failed because the package stash has no name.
1116
b8170e59
JB
1117=item Can't load '%s' for module %s
1118
6903afa2
FC
1119(F) The module you tried to load failed to load a dynamic extension.
1120This may either mean that you upgraded your version of perl to one
1121that is incompatible with your old dynamic extensions (which is known
1122to happen between major versions of perl), or (more likely) that your
1123dynamic extension was built against an older version of the library
1124that is installed on your system. You may need to rebuild your old
1125dynamic extensions.
b8170e59 1126
748a9306
LW
1127=item Can't localize lexical variable %s
1128
2ba9eb46 1129(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
1130lexical variable using "my" or "state". This is not allowed. If you
1131want to localize a package variable of the same name, qualify it with
1132the package name.
748a9306 1133
6df41af2 1134=item Can't localize through a reference
4727527e 1135
6df41af2
GS
1136(F) You said something like C<local $$ref>, which Perl can't currently
1137handle, because when it goes to restore the old value of whatever $ref
be771a83 1138pointed to after the scope of the local() is finished, it can't be sure
64977eb6 1139that $ref will still be a reference.
4727527e 1140
ea071790 1141=item Can't locate %s
ec889f3a 1142
fa816bf3
FC
1143(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
1144Perl looks for the file in all the locations mentioned in @INC, unless
1145the file name included the full path to the file. Perhaps you need
1146to set the PERL5LIB or PERL5OPT environment variable to say where the
1147extra library is, or maybe the script needs to add the library name
be771a83
GS
1148to @INC. Or maybe you just misspelled the name of the file. See
1149L<perlfunc/require> and L<lib>.
a0d0e21e 1150
6df41af2
GS
1151=item Can't locate auto/%s.al in @INC
1152
be771a83
GS
1153(F) A function (or method) was called in a package which allows
1154autoload, but there is no function to autoload. Most probable causes
1155are a misprint in a function/method name or a failure to C<AutoSplit>
1156the file, say, by doing C<make install>.
6df41af2 1157
b8170e59
JB
1158=item Can't locate loadable object for module %s in @INC
1159
1160(F) The module you loaded is trying to load an external library, like
d70d8e57 1161for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1162unable to locate this library. See L<DynaLoader>.
1163
a0d0e21e
LW
1164=item Can't locate object method "%s" via package "%s"
1165
1166(F) You called a method correctly, and it correctly indicated a package
1167functioning as a class, but that package doesn't define that particular
2ba9eb46 1168method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1169
8af56b9d
FC
1170=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1171to load "%s"?)
1172
1173(F) You called a method on a class that did not exist, and the method
1174could not be found in UNIVERSAL. This often means that a method
1175requires a package that has not been loaded.
1176
a0d0e21e
LW
1177=item Can't locate package %s for @%s::ISA
1178
be771a83
GS
1179(W syntax) The @ISA array contained the name of another package that
1180doesn't seem to exist.
a0d0e21e 1181
2f7da168
RK
1182=item Can't locate PerlIO%s
1183
1184(F) You tried to use in open() a PerlIO layer that does not exist,
1185e.g. open(FH, ">:nosuchlayer", "somefile").
1186
f4ad53f4 1187=item Can't make list assignment to %ENV on this system
3e3baf6d 1188
be771a83
GS
1189(F) List assignment to %ENV is not supported on some systems, notably
1190VMS.
3e3baf6d 1191
cd40cd58
NC
1192=item Can't make loaded symbols global on this platform while loading %s
1193
ff9c1ae8 1194(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1195that symbols from the stated file are made available globally within the
1196process, but that functionality is not available on this platform. Whilst
1197the module likely will still work, this may prevent the perl interpreter
1198from loading other XS-based extensions which need to link directly to
1199functions defined in the C or XS code in the stated file.
1200
a0d0e21e
LW
1201=item Can't modify %s in %s
1202
be771a83
GS
1203(F) You aren't allowed to assign to the item indicated, or otherwise try
1204to change it, such as with an auto-increment.
a0d0e21e 1205
54310121 1206=item Can't modify nonexistent substring
a0d0e21e
LW
1207
1208(P) The internal routine that does assignment to a substr() was handed
1209a NULL.
1210
0f948285 1211=item Can't modify non-lvalue subroutine call of &%s
6df41af2 1212
8d9d0498
FC
1213=item Can't modify non-lvalue subroutine call of &%s in %s
1214
6df41af2 1215(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1216such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1217
cf6e1fa1
FC
1218=item Can't modify reference to %s in %s assignment
1219
1220(F) Only a limited number of constructs can be used as the argument to a
1221reference constructor on the left-hand side of an assignment, and what
1222you used was not one of them. See L<perlref/Assigning to References>.
1223
1224=item Can't modify reference to localized parenthesized array in list
1225assignment
1226
1227(F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1228it is not clear exactly what it should do. If you meant to make @array
1229refer to some other array, use C<\@array = \@other_array>. If you want to
1230make the elements of @array aliases of the scalars referenced on the
1231right-hand side, use C<\(@array) = @scalar_refs>.
1232
1233=item Can't modify reference to parenthesized hash in list assignment
1234
1235(F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1236refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1237make the elements of %hash into aliases of the scalars referenced on the
1238right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1239
5f05dabc 1240=item Can't msgrcv to read-only var
a0d0e21e 1241
5f05dabc 1242(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1243buffer.
1244
6df41af2
GS
1245=item Can't "next" outside a loop block
1246
1247(F) A "next" statement was executed to reiterate the current block, but
1248there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1249count as a "loopish" block, as doesn't a block given to sort(), map() or
1250grep(). You can usually double the curlies to get the same effect
1251though, because the inner curlies will be considered a block that loops
1252once. See L<perlfunc/next>.
6df41af2 1253
a0d0e21e
LW
1254=item Can't open %s: %s
1255
c47ff5f1 1256(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1257filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1258switches, or explicitly, failed for the indicated reason. Usually
1259this is because you don't have read permission for a file which
1260you named on the command line.
1261
1262(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1263your operating system's equivalent) could not be opened.
a0d0e21e 1264
9a869a14
RGS
1265=item Can't open a reference
1266
1267(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1268using the 3-arg open() syntax:
9a869a14
RGS
1269
1270 open FH, '>', $ref;
1271
1272but your version of perl is compiled without perlio, and this form of
1273open is not supported.
1274
a0d0e21e
LW
1275=item Can't open bidirectional pipe
1276
be771a83
GS
1277(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1278You can try any of several modules in the Perl library to do this, such
1279as IPC::Open2. Alternately, direct the pipe's output to a file using
1280">", and then read it in under a different file handle.
a0d0e21e 1281
748a9306
LW
1282=item Can't open error file %s as stderr
1283
be771a83
GS
1284(F) An error peculiar to VMS. Perl does its own command line
1285redirection, and couldn't open the file specified after '2>' or '2>>' on
1286the command line for writing.
748a9306
LW
1287
1288=item Can't open input file %s as stdin
1289
be771a83
GS
1290(F) An error peculiar to VMS. Perl does its own command line
1291redirection, and couldn't open the file specified after '<' on the
1292command line for reading.
748a9306
LW
1293
1294=item Can't open output file %s as stdout
1295
be771a83
GS
1296(F) An error peculiar to VMS. Perl does its own command line
1297redirection, and couldn't open the file specified after '>' or '>>' on
1298the command line for writing.
748a9306
LW
1299
1300=item Can't open output pipe (name: %s)
1301
be771a83
GS
1302(P) An error peculiar to VMS. Perl does its own command line
1303redirection, and couldn't open the pipe into which to send data destined
1304for stdout.
748a9306 1305
3b1cf97d 1306=item Can't open perl script "%s": %s
a0d0e21e
LW
1307
1308(F) The script you specified can't be opened for the indicated reason.
1309
fa3aa65a
JC
1310If you're debugging a script that uses #!, and normally relies on the
1311shell's $PATH search, the -S option causes perl to do that search, so
1312you don't have to type the path or C<`which $scriptname`>.
1313
6df41af2
GS
1314=item Can't read CRTL environ
1315
1316(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1317from the CRTL's internal environment array and discovered the array was
1318missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1319or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1320searched.
6df41af2 1321
f3106bc8
LM
1322=item Can't redeclare "%s" in "%s"
1323
1324(F) A "my", "our" or "state" declaration was found within another declaration,
1325such as C<my ($x, my($y), $z)> or C<our (my $x)>.
1326
6df41af2
GS
1327=item Can't "redo" outside a loop block
1328
1329(F) A "redo" statement was executed to restart the current block, but
1330there isn't a current block. Note that an "if" or "else" block doesn't
1331count as a "loopish" block, as doesn't a block given to sort(), map()
1332or grep(). You can usually double the curlies to get the same effect
1333though, because the inner curlies will be considered a block that
1334loops once. See L<perlfunc/redo>.
1335
64977eb6 1336=item Can't remove %s: %s, skipping file
10f9c03d 1337
be771a83
GS
1338(S inplace) You requested an inplace edit without creating a backup
1339file. Perl was unable to remove the original file to replace it with
1340the modified file. The file was left unmodified.
10f9c03d 1341
e0d4aead
TC
1342=item Can't rename in-place work file '%s' to '%s': %s
1343
1344(F) When closed implicitly, the temporary file for in-place editing
1345couldn't be renamed to the original filename.
1346
ecc6274e
FC
1347=item Can't rename %s to %s: %s, skipping file
1348
1349(F) The rename done by the B<-i> switch failed for some reason,
1350probably because you don't have write permission to the directory.
1351
748a9306
LW
1352=item Can't reopen input pipe (name: %s) in binary mode
1353
be771a83
GS
1354(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1355to reopen it to accept binary data. Alas, it failed.
748a9306 1356
9415f659
KW
1357=item Can't represent character for Ox%X on this platform
1358
1359(F) There is a hard limit to how big a character code point can be due
1360to the fundamental properties of UTF-8, especially on EBCDIC
1361platforms. The given code point exceeds that. The only work-around is
1362to not use such a large code point.
1363
4f12ec0e
FC
1364=item Can't reset %ENV on this system
1365
1366(F) You called C<reset('E')> or similar, which tried to reset
1367all variables in the current package beginning with "E". In
1368the main package, that includes %ENV. Resetting %ENV is not
1369supported on some systems, notably VMS.
1370
fe13d51d 1371=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1372
1fa582fa
FC
1373(F)(P) Error resolving overloading specified by a method name (as
1374opposed to a subroutine reference): no such method callable via the
1375package. If the method name is C<???>, this is an internal error.
6df41af2 1376
cd06dffe
GS
1377=item Can't return %s from lvalue subroutine
1378
be771a83
GS
1379(F) Perl detected an attempt to return illegal lvalues (such as
1380temporary or readonly values) from a subroutine used as an lvalue. This
1381is not allowed.
cd06dffe 1382
96ebfdd7
RK
1383=item Can't return outside a subroutine
1384
1385(F) The return statement was executed in mainline code, that is, where
1386there was no subroutine call to return out of. See L<perlsub>.
1387
78f9721b
SM
1388=item Can't return %s to lvalue scalar context
1389
6903afa2
FC
1390(F) You tried to return a complete array or hash from an lvalue
1391subroutine, but you called the subroutine in a way that made Perl
1392think you meant to return only one value. You probably meant to
1393write parentheses around the call to the subroutine, which tell
1394Perl that the call should be in list context.
78f9721b 1395
a0d0e21e
LW
1396=item Can't stat script "%s"
1397
be771a83
GS
1398(P) For some reason you can't fstat() the script even though you have it
1399open already. Bizarre.
a0d0e21e 1400
a0d0e21e
LW
1401=item Can't take log of %g
1402
fb73857a 1403(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1404negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1405standard with Perl, though, if you really want to do that for the
1406negative numbers.
a0d0e21e
LW
1407
1408=item Can't take sqrt of %g
1409
1410(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1411negative number. There's a Math::Complex package that comes standard
1412with Perl, though, if you really want to do that.
a0d0e21e
LW
1413
1414=item Can't undef active subroutine
1415
1416(F) You can't undefine a routine that's currently running. You can,
1417however, redefine it while it's running, and you can even undef the
1418redefined subroutine while the old routine is running. Go figure.
1419
ecc6274e
FC
1420=item Can't unweaken a nonreference
1421
1422(F) You attempted to unweaken something that was not a reference. Only
1423references can be unweakened.
1424
c81225bc 1425=item Can't upgrade %s (%d) to %d
a0d0e21e 1426
be771a83
GS
1427(P) The internal sv_upgrade routine adds "members" to an SV, making it
1428into a more specialized kind of SV. The top several SV types are so
1429specialized, however, that they cannot be interconverted. This message
1430indicates that such a conversion was attempted.
a0d0e21e 1431
6651ba0b
FC
1432=item Can't use '%c' after -mname
1433
1434(F) You tried to call perl with the B<-m> switch, but you put something
1435other than "=" after the module name.
1436
1f1ec7b5
KW
1437=item Can't use a hash as a reference
1438
1439(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1440C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1441<= 5.22.0 used to allow this syntax, but shouldn't
1442have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1443
1444=item Can't use an array as a reference
1445
1446(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1447C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1448used to allow this syntax, but shouldn't have. This
1449was deprecated in perl 5.6.1.
1f1ec7b5 1450
1db89ea5
BS
1451=item Can't use anonymous symbol table for method lookup
1452
e27ad1f2 1453(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1454table that doesn't have a name. Symbol tables can become anonymous
1455for example by undefining stashes: C<undef %Some::Package::>.
1456
96ebfdd7
RK
1457=item Can't use an undefined value as %s reference
1458
1459(F) A value used as either a hard reference or a symbolic reference must
1460be a defined value. This helps to delurk some insidious errors.
1461
6df41af2
GS
1462=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1463
be771a83
GS
1464(F) Only hard references are allowed by "strict refs". Symbolic
1465references are disallowed. See L<perlref>.
6df41af2 1466
90b75b61 1467=item Can't use %! because Errno.pm is not available
1d2dff63 1468
20561843 1469(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1470Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1471provide symbolic names for C<$!> errno values.
1472
1109a392
MHM
1473=item Can't use both '<' and '>' after type '%c' in %s
1474
1475(F) A type cannot be forced to have both big-endian and little-endian
1476byte-order at the same time, so this combination of modifiers is not
1477allowed. See L<perlfunc/pack>.
1478
e35475de
KW
1479=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1480
1481(F) defined() is not useful on arrays because it
1482checks for an undefined I<scalar> value. If you want to see if the
1483array is empty, just use C<if (@array) { # not empty }> for example.
1484
1485=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1486
1487(F) C<defined()> is not usually right on hashes.
1488
1489Although C<defined %hash> is false on a plain not-yet-used hash, it
1490becomes true in several non-obvious circumstances, including iterators,
1491weak references, stash names, even remaining true after C<undef %hash>.
1492These things make C<defined %hash> fairly useless in practice, so it now
1493generates a fatal error.
1494
1495If a check for non-empty is what you wanted then just put it in boolean
1496context (see L<perldata/Scalar values>):
1497
1498 if (%hash) {
1499 # not empty
1500 }
1501
1502If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1503variable exists then that's never really been reliable, and isn't
1504a good way to enquire about the features of a package, or whether
1505it's loaded, etc.
1506
6df41af2
GS
1507=item Can't use %s for loop variable
1508
c1f06047 1509(P) The parser got confused when trying to parse a C<foreach> loop.
6df41af2 1510
f27832e7 1511=item Can't use global %s in %s
6df41af2 1512
be771a83
GS
1513(F) You tried to declare a magical variable as a lexical variable. This
1514is not allowed, because the magic can be tied to only one location
1515(namely the global variable) and it would be incredibly confusing to
1516have variables in your program that looked like magical variables but
6df41af2
GS
1517weren't.
1518
6d3b25aa
RGS
1519=item Can't use '%c' in a group with different byte-order in %s
1520
1521(F) You attempted to force a different byte-order on a type
1522that is already inside a group with a byte-order modifier.
1523For example you cannot force little-endianness on a type that
1524is inside a big-endian group.
1525
c07a80fd
PP
1526=item Can't use "my %s" in sort comparison
1527
1528(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1529You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1530and the variable had earlier been declared as a lexical variable.
1531Either qualify the sort variable with the package name, or rename the
1532lexical variable.
1533
a0d0e21e
LW
1534=item Can't use %s ref as %s ref
1535
1536(F) You've mixed up your reference types. You have to dereference a
1537reference of the type needed. You can use the ref() function to
1538test the type of the reference, if need be.
1539
748a9306 1540=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1541
5e634d20
FC
1542=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1543
b41bf23f
FC
1544(F) You've told Perl to dereference a string, something which
1545C<use strict> blocks to prevent it happening accidentally. See
1546L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1547in a double-quoted string immediately before interpolating a variable,
1548for example in C<"user @$twitter_id">, which says to treat the contents
1549of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1550symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1551
748a9306
LW
1552=item Can't use subscript on %s
1553
1554(F) The compiler tried to interpret a bracketed expression as a
1555subscript. But to the left of the brackets was an expression that
209e7cf1 1556didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1557
6df41af2
GS
1558=item Can't use \%c to mean $%c in expression
1559
75b44862
GS
1560(W syntax) In an ordinary expression, backslash is a unary operator that
1561creates a reference to its argument. The use of backslash to indicate a
1562backreference to a matched substring is valid only as part of a regular
be771a83
GS
1563expression pattern. Trying to do this in ordinary Perl code produces a
1564value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1565instead.
6df41af2 1566
810b8aa5
GS
1567=item Can't weaken a nonreference
1568
1569(F) You attempted to weaken something that was not a reference. Only
1570references can be weakened.
1571
7896dde7
Z
1572=item Can't "when" outside a topicalizer
1573
1574(F) You have used a when() block that is neither inside a C<foreach>
1575loop nor a C<given> block. (Note that this error is issued on exit
1576from the C<when> block, so you won't get the error if the match fails,
1577or if you use an explicit C<continue>.)
1578
5f05dabc 1579=item Can't x= to read-only value
a0d0e21e 1580
be771a83
GS
1581(F) You tried to repeat a constant value (often the undefined value)
1582with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1583Perhaps you need to copy the value to a temporary, and repeat that.
1584
a04e6aad 1585=item Character following "\c" must be printable ASCII
f9d13529 1586
7357bd17 1587(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1588
727b6379 1589Note that ASCII characters that don't map to control characters are
7357bd17 1590discouraged, and will generate the warning (when enabled)
d4360efa 1591L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1592
163a633c
KW
1593=item Character following \%c must be '{' or a single-character Unicode property name in regex; marked by <-- HERE in m/%s/
1594
1595(F) (In the above the C<%c> is replaced by either C<p> or C<P>.) You
1596specified something that isn't a legal Unicode property name. Most
1597Unicode properties are specified by C<\p{...}>. But if the name is a
1598single character one, the braces may be omitted.
1599
f337b084 1600=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1601
1602(W pack) You said
1603
1604 pack("C", $x)
1605
1606where $x is either less than 0 or more than 255; the C<"C"> format is
1607only for encoding native operating system characters (ASCII, EBCDIC,
1608and so on) and not for Unicode characters, so Perl behaved as if you meant
1609
1610 pack("C", $x & 255)
1611
1612If you actually want to pack Unicode codepoints, use the C<"U"> format
1613instead.
1614
f337b084 1615=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1616
1617(W pack) You said
1618
1619 pack("c", $x)
1620
1621where $x is either less than -128 or more than 127; the C<"c"> format
1622is only for encoding native operating system characters (ASCII, EBCDIC,
1623and so on) and not for Unicode characters, so Perl behaved as if you meant
1624
1625 pack("c", $x & 255);
1626
1627If you actually want to pack Unicode codepoints, use the C<"U"> format
1628instead.
1629
f337b084
TH
1630=item Character in '%c' format wrapped in unpack
1631
1632(W unpack) You tried something like
1633
1634 unpack("H", "\x{2a1}")
1635
1a147d38 1636where the format expects to process a byte (a character with a value
6903afa2
FC
1637below 256), but a higher value was provided instead. Perl uses the
1638value modulus 256 instead, as if you had provided:
f337b084
TH
1639
1640 unpack("H", "\x{a1}")
1641
5a25739d
FC
1642=item Character in 'W' format wrapped in pack
1643
1644(W pack) You said
1645
1646 pack("U0W", $x)
1647
1648where $x is either less than 0 or more than 255. However, C<U0>-mode
1649expects all values to fall in the interval [0, 255], so Perl behaved
1650as if you meant:
1651
1652 pack("U0W", $x & 255)
1653
f337b084
TH
1654=item Character(s) in '%c' format wrapped in pack
1655
1656(W pack) You tried something like
1657
1658 pack("u", "\x{1f3}b")
1659
1a147d38 1660where the format expects to process a sequence of bytes (character with a
6903afa2 1661value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1662uses the character values modulus 256 instead, as if you had provided:
1663
1664 pack("u", "\x{f3}b")
1665
1666=item Character(s) in '%c' format wrapped in unpack
1667
1668(W unpack) You tried something like
1669
1670 unpack("s", "\x{1f3}b")
1671
1a147d38 1672where the format expects to process a sequence of bytes (character with a
6903afa2 1673value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1674uses the character values modulus 256 instead, as if you had provided:
1675
1676 unpack("s", "\x{f3}b")
1677
8d9d0498
FC
1678=item charnames alias definitions may not contain a sequence of multiple
1679spaces; marked by S<<-- HERE> in %s
f51551f7
FC
1680
1681(F) You defined a character name which had multiple space characters
1682in a row. Change them to single spaces. Usually these names are
1683defined in the C<:alias> import argument to C<use charnames>, but they
1684could be defined by a translator installed into C<$^H{charnames}>. See
1685L<charnames/CUSTOM ALIASES>.
1686
8d9d0498
FC
1687=item charnames alias definitions may not contain trailing white-space;
1688marked by S<<-- HERE> in %s
f51551f7
FC
1689
1690(F) You defined a character name which ended in a space
1691character. Remove the trailing space(s). Usually these names are
1692defined in the C<:alias> import argument to C<use charnames>, but they
1693could be defined by a translator installed into C<$^H{charnames}>.
1694See L<charnames/CUSTOM ALIASES>.
1695
60121127
TC
1696=item chdir() on unopened filehandle %s
1697
1698(W unopened) You tried chdir() on a filehandle that was never opened.
1699
d4360efa 1700=item "\c%c" is more clearly written simply as "%s"
f866a7cd 1701
d4360efa
S
1702(W syntax) The C<\cI<X>> construct is intended to be a way to specify
1703non-printable characters. You used it for a printable one, which
1704is better written as simply itself, perhaps preceded by a backslash
1705for non-word characters. Doing it the way you did is not portable
1706between ASCII and EBCDIC platforms.
f866a7cd 1707
6651ba0b
FC
1708=item Cloning substitution context is unimplemented
1709
1710(F) Creating a new thread inside the C<s///> operator is not supported.
1711
abc7ecad
SP
1712=item closedir() attempted on invalid dirhandle %s
1713
1714(W io) The dirhandle you tried to close is either closed or not really
1715a dirhandle. Check your control flow.
1716
5a25739d
FC
1717=item close() on unopened filehandle %s
1718
1719(W unopened) You tried to close a filehandle that was never opened.
1720
541ed3a9
FC
1721=item Closure prototype called
1722
1723(F) If a closure has attributes, the subroutine passed to an attribute
1724handler is the prototype that is cloned when a new closure is created.
1725This subroutine cannot be called.
1726
74d1b2e4
FC
1727=item \C no longer supported in regex; marked by S<<-- HERE> in m/%s/
1728
1729(F) The \C character class used to allow a match of single byte
1730within a multi-byte utf-8 character, but was removed in v5.24 as
1731it broke encapsulation and its implementation was extremely buggy.
1732If you really need to process the individual bytes, you probably
1733want to convert your string to one where each underlying byte is
1734stored as a character, with utf8::encode().
1735
49704364
LW
1736=item Code missing after '/'
1737
6903afa2
FC
1738(F) You had a (sub-)template that ends with a '/'. There must be
1739another template code following the slash. See L<perlfunc/pack>.
49704364 1740
c0236afe
KW
1741=item Code point 0x%X is not Unicode, and not portable
1742
dc4a6683 1743(S non_unicode portable) You had a code point that has never been in any
c0236afe 1744standard, so it is likely that languages other than Perl will NOT
dc4a6683
KW
1745understand it. This code point also will not fit in a 32-bit word on
1746ASCII platforms and therefore is non-portable between systems.
1747
1748At one time, it was legal in some standards to have code points up to
17490x7FFF_FFFF, but not higher, and this code point is higher.
c0236afe
KW
1750
1751Acceptance of these code points is a Perl extension, and you should
1752expect that nothing other than Perl can handle them; Perl itself on
1753EBCDIC platforms before v5.24 does not handle them.
1754
c0236afe
KW
1755Perl also makes no guarantees that the representation of these code
1756points won't change at some point in the future, say when machines
1757become available that have larger than a 64-bit word. At that time,
aaa9d2b4
KW
1758files containing any of these, written by an older Perl might require
1759conversion before being readable by a newer Perl.
c0236afe 1760
5a25739d
FC
1761=item Code point 0x%X is not Unicode, may not be portable
1762
2d88a86a 1763(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1764of U+10FFFF.
1765
c0236afe
KW
1766Perl allows strings to contain a superset of Unicode code points, but
1767these may not be accepted by other languages/systems. Further, even if
1768these languages/systems accept these large code points, they may have
1769chosen a different representation for them than the UTF-8-like one that
1770Perl has, which would mean files are not exchangeable between them and
1771Perl.
1772
1773On EBCDIC platforms, code points above 0x3FFF_FFFF have a different
1774representation in Perl v5.24 than before, so any file containing these
1775that was written before that version will require conversion before
1776being readable by a later Perl.
0876b9a0 1777
6df41af2
GS
1778=item %s: Command not found
1779
a892b81a 1780(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1781instead of Perl. Check the #! line, or manually feed your script into
1782Perl yourself. The #! line at the top of your file could look like
8f721816 1783
3bcfc7b3
LM
1784 #!/usr/bin/perl
1785
1786=item %s: command not found
1787
1788(A) You've accidentally run your script through B<bash> or another shell
1789instead of Perl. Check the #! line, or manually feed your script into
1790Perl yourself. The #! line at the top of your file could look like
1791
1792 #!/usr/bin/perl
1793
1794=item %s: command not found: %s
1795
1796(A) You've accidentally run your script through B<zsh> or another shell
1797instead of Perl. Check the #! line, or manually feed your script into
1798Perl yourself. The #! line at the top of your file could look like
1799
1800 #!/usr/bin/perl
6df41af2 1801
7a2e2cd6
PP
1802=item Compilation failed in require
1803
1804(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1805Perl uses this generic message when none of the errors that it
1806encountered were severe enough to halt compilation immediately.
7a2e2cd6 1807
c3464db5
DD
1808=item Complex regular subexpression recursion limit (%d) exceeded
1809
be771a83
GS
1810(W regexp) The regular expression engine uses recursion in complex
1811situations where back-tracking is required. Recursion depth is limited
1812to 32766, or perhaps less in architectures where the stack cannot grow
1813arbitrarily. ("Simple" and "medium" situations are handled without
1814recursion and are not subject to a limit.) Try shortening the string
1815under examination; looping in Perl code (e.g. with C<while>) rather than
1816in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1817that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1818on I<Mastering Regular Expressions>.)
c3464db5 1819
69282e91 1820=item connect() on closed socket %s
a0d0e21e 1821
be771a83
GS
1822(W closed) You tried to do a connect on a closed socket. Did you forget
1823to check the return value of your socket() call? See
1824L<perlfunc/connect>.
a0d0e21e 1825
e21e7c6a
FC
1826=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1827
1828(F) The subroutine registered to handle constant overloading
1829(see L<overload>) or a custom charnames handler (see
1830L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1831
1832=item Constant(%s): $^H{%s} is not defined
1833
1834(F) The parser found inconsistencies while attempting to define an
1835overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1836L<overload> pragma?
e21e7c6a 1837
779c5bc9
GS
1838=item Constant is not %s reference
1839
1840(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1841is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1842The message indicates the type of reference that was expected. This
be771a83 1843usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1844See L<perlsub/"Constant Functions"> and L<constant>.
1845
30fc7a28 1846=item Constants from lexical variables potentially modified elsewhere are no longer permitted
0ac016fc 1847
30fc7a28 1848(F) You wrote something like
0ac016fc
FC
1849
1850 my $var;
1851 $sub = sub () { $var };
1852
1853but $var is referenced elsewhere and could be modified after the C<sub>
1854expression is evaluated. Either it is explicitly modified elsewhere
1855(C<$var = 3>) or it is passed to a subroutine or to an operator like
1856C<printf> or C<map>, which may or may not modify the variable.
1857
1858Traditionally, Perl has captured the value of the variable at that
1859point and turned the subroutine into a constant eligible for inlining.
1860In those cases where the variable can be modified elsewhere, this
1861breaks the behavior of closures, in which the subroutine captures
1862the variable itself, rather than its value, so future changes to the
1863variable are reflected in the subroutine's return value.
1864
30fc7a28 1865This usage was deprecated, and as of Perl 5.32 is no longer allowed,
9840d1d6 1866making it possible to change the behavior in the future.
0ac016fc
FC
1867
1868If you intended for the subroutine to be eligible for inlining, then
1869make sure the variable is not referenced elsewhere, possibly by
1870copying it:
1871
1872 my $var2 = $var;
1873 $sub = sub () { $var2 };
1874
1875If you do want this subroutine to be a closure that reflects future
1876changes to the variable that it closes over, add an explicit C<return>:
1877
1878 my $var;
1879 $sub = sub () { return $var };
1880
4cee8e80
CS
1881=item Constant subroutine %s redefined
1882
aeb94125
FC
1883(W redefine)(S) You redefined a subroutine which had previously
1884been eligible for inlining. See L<perlsub/"Constant Functions">
1885for commentary and workarounds.
4cee8e80 1886
9607fc9c
PP
1887=item Constant subroutine %s undefined
1888
be771a83
GS
1889(W misc) You undefined a subroutine which had previously been eligible
1890for inlining. See L<perlsub/"Constant Functions"> for commentary and
1891workarounds.
9607fc9c 1892
5a25739d
FC
1893=item Constant(%s) unknown
1894
1895(F) The parser found inconsistencies either while attempting
1896to define an overloaded constant, or when trying to find the
1897character name specified in the C<\N{...}> escape. Perhaps you
3ee1a09c 1898forgot to load the corresponding L<overload> pragma?
5a25739d 1899
4a873d7a
FC
1900=item :const is experimental
1901
1902(S experimental::const_attr) The "const" attribute is experimental.
1903If you want to use the feature, disable the warning with C<no warnings
1904'experimental::const_attr'>, but know that in doing so you are taking
1905the risk that your code may break in a future Perl version.
1906
b77472f9
FC
1907=item :const is not permitted on named subroutines
1908
1909(F) The "const" attribute causes an anonymous subroutine to be run and
465068b9 1910its value captured at the time that it is cloned. Named subroutines are
b77472f9
FC
1911not cloned like this, so the attribute does not make sense on them.
1912
e7ea3e70
IZ
1913=item Copy method did not return a reference
1914
6903afa2 1915(F) The method which overloads "=" is buggy. See
13a2d996 1916L<overload/Copy Constructor>.
e7ea3e70 1917
4aaa4757
FC
1918=item &CORE::%s cannot be called directly
1919
1920(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1921with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1922in this package cannot yet be called that way, but must be
1923called as barewords. Something like this will work:
1924
1925 BEGIN { *shove = \&CORE::push; }
1926 shove @array, 1,2,3; # pushes on to @array
1927
6798c92b
GS
1928=item CORE::%s is not a keyword
1929
1930(F) The CORE:: namespace is reserved for Perl keywords.
1931
675fa9ff
FC
1932=item Corrupted regexp opcode %d > %d
1933
1934(P) This is either an error in Perl, or, if you're using
1935one, your L<custom regular expression engine|perlreapi>. If not the
8166b4e0 1936latter, report the problem to L<https://github.com/Perl/perl5/issues>.
675fa9ff 1937
a0d0e21e
LW
1938=item corrupted regexp pointers
1939
1940(P) The regular expression engine got confused by what the regular
1941expression compiler gave it.
1942
1943=item corrupted regexp program
1944
be771a83
GS
1945(P) The regular expression engine got passed a regexp program without a
1946valid magic number.
a0d0e21e 1947
de42a5a9 1948=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1949
1950(P) The malloc package that comes with Perl had an internal failure.
1951
49704364
LW
1952=item Count after length/code in unpack
1953
1954(F) You had an unpack template indicating a counted-length string, but
1955you have also specified an explicit size for the string. See
1956L<perlfunc/pack>.
1957
3f645a4e
FC
1958=item Declaring references is experimental
1959
1960(S experimental::declared_refs) This warning is emitted if you use
1961a reference constructor on the right-hand side of C<my>, C<state>, C<our>, or
1962C<local>. Simply suppress the warning if you want to use the feature, but
1963know that in doing so you are taking the risk of using an experimental
1964feature which may change or be removed in a future Perl version:
1965
1966 no warnings "experimental::declared_refs";
1967 use feature "declared_refs";
1968 $fooref = my \$foo;
1969
f2cccb4c
KW
1970=for comment
1971The following are used in lib/diagnostics.t for testing two =items that
1972share the same description. Changes here need to be propagated to there
1973
6651ba0b
FC
1974=item Deep recursion on anonymous subroutine
1975
a0d0e21e
LW
1976=item Deep recursion on subroutine "%s"
1977
be771a83
GS
1978(W recursion) This subroutine has called itself (directly or indirectly)
1979100 times more than it has returned. This probably indicates an
1980infinite recursion, unless you're writing strange benchmark programs, in
1981which case it indicates something else.
a0d0e21e 1982
aad1d01f
NC
1983This threshold can be changed from 100, by recompiling the F<perl> binary,
1984setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1985
e0e4a6e3
FC
1986=item (?(DEFINE)....) does not allow branches in regex; marked by
1987S<<-- HERE> in m/%s/
bcb95744 1988
6903afa2 1989(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1990most likely cause of this error is that you left out a parenthesis inside
1991of the C<....> part.
1992
6e8a73f2 1993The S<<-- HERE> shows whereabouts in the regular expression the problem was
bcb95744
FC
1994discovered.
1995
62658f4d
PM
1996=item %s defines neither package nor VERSION--version check failed
1997
1998(F) You said something like "use Module 42" but in the Module file
1999there are neither package declarations nor a C<$VERSION>.
2000
0ffcbc25
FC
2001=item delete argument is not a HASH or ARRAY element or slice
2002
4a0af295 2003(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
2004such as:
2005
2006 $foo{$bar}
2007 $ref->{"susie"}[12]
2008
2009or a hash or array slice, such as:
2010
2011 @foo[$bar, $baz, $xyzzy]
39104754 2012 $ref->[12]->@{"susie", "queue"}
0ffcbc25 2013
cc0776d6
DIM
2014or a hash key/value or array index/value slice, such as:
2015
2016 %foo[$bar, $baz, $xyzzy]
39104754 2017 $ref->[12]->%{"susie", "queue"}
cc0776d6 2018
fc36a67e
PP
2019=item Delimiter for here document is too long
2020
be771a83
GS
2021(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
2022long for Perl to handle. You have to be seriously twisted to write code
2023that triggers this error.
fc36a67e 2024
c437f7ac 2025=item Deprecated use of my() in false conditional. This will be a fatal error in Perl 5.30
6d3b25aa 2026
fa816bf3
FC
2027(D deprecated) You used a declaration similar to C<my $x if 0>. There
2028has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 2029not to be cleared at scope exit when its declaration includes a false
6903afa2 2030conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 2031static variable. Since we intend to fix this bug, we don't want people
6903afa2 2032relying on this behavior. You can achieve a similar static effect by
6d3b25aa 2033declaring the variable in a separate block outside the function, eg
36fb85f3 2034
6d3b25aa
RGS
2035 sub f { my $x if 0; return $x++ }
2036
2037becomes
2038
2039 { my $x; sub f { return $x++ } }
2040
ea9d9ebc 2041Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 2042lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
2043
2044 sub f { state $x; return $x++ }
2045
c437f7ac
A
2046This use of C<my()> in a false conditional has been deprecated since
2047Perl 5.10, and it will become a fatal error in Perl 5.30.
2048
500ab966
RGS
2049=item DESTROY created new reference to dead object '%s'
2050
2051(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
2052just being DESTROYed. Perl is confused, and prefers to abort rather
2053than to create a dangling reference.
500ab966 2054
3cdd684c
TP
2055=item Did not produce a valid header
2056
3de20fbe 2057See L</500 Server error>.
3cdd684c 2058
6df41af2
GS
2059=item %s did not return a true value
2060
2061(F) A required (or used) file must return a true value to indicate that
2062it compiled correctly and ran its initialization code correctly. It's
2063traditional to end such a file with a "1;", though any true value would
2064do. See L<perlfunc/require>.
2065
cc507455 2066=item (Did you mean &%s instead?)
4633a7c4 2067
413ff9f6
FC
2068(W misc) You probably referred to an imported subroutine &FOO as $FOO or
2069some such.
4633a7c4 2070
cc507455 2071=item (Did you mean "local" instead of "our"?)
33633739 2072
52e3acf8 2073(W shadow) Remember that "our" does not localize the declared global
be771a83
GS
2074variable. You have declared it again in the same lexical scope, which
2075seems superfluous.
33633739 2076
cc507455 2077=item (Did you mean $ or @ instead of %?)
a0d0e21e 2078
be771a83
GS
2079(W) You probably said %hash{$key} when you meant $hash{$key} or
2080@hash{@keys}. On the other hand, maybe you just meant %hash and got
2081carried away.
748a9306 2082
7e1af8bc 2083=item Died
5f05dabc
PP
2084
2085(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 2086you called it with no args and C<$@> was empty.
5f05dabc 2087
3cdd684c
TP
2088=item Document contains no data
2089
3de20fbe 2090See L</500 Server error>.
3cdd684c 2091
62658f4d
PM
2092=item %s does not define %s::VERSION--version check failed
2093
2094(F) You said something like "use Module 42" but the Module did not
943fc58e 2095define a C<$VERSION>.
62658f4d 2096
49704364
LW
2097=item '/' does not take a repeat count
2098
2099(F) You cannot put a repeat count of any kind right after the '/' code.
2100See L<perlfunc/pack>.
2101
1c99110e 2102=item do "%s" failed, '.' is no longer in @INC; did you mean do "./%s"?
2a0461a3 2103
b28683c9 2104(D deprecated) Previously C< do "somefile"; > would search the current
1c99110e
DM
2105directory for the specified file. Since perl v5.26.0, F<.> has been
2106removed from C<@INC> by default, so this is no longer true. To search the
2107current directory (and only the current directory) you can write
2108C< do "./somefile"; >.
2a0461a3 2109
95cb0d72
FC
2110=item Don't know how to get file name
2111
2112(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
2113somehow called on another platform. This should not happen.
2114
4021c788 2115=item Don't know how to handle magic of type \%o
a0d0e21e
LW
2116
2117(P) The internal handling of magical variables has been cursed.
2118
2119=item do_study: out of memory
2120
2121(P) This should have been caught by safemalloc() instead.
2122
6df41af2
GS
2123=item (Do you need to predeclare %s?)
2124
56da5a46
RGS
2125(S syntax) This is an educated guess made in conjunction with the message
2126"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
2127name is being referenced that hasn't been declared yet. This may be
2128because of ordering problems in your file, or because of a missing
be771a83
GS
2129"sub", "package", "require", or "use" statement. If you're referencing
2130something that isn't defined yet, you don't actually have to define the
2131subroutine or package before the current location. You can use an empty
2132"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 2133
d8ff3e95 2134=item dump() must be written as CORE::dump() as of Perl 5.30
ac206dc8 2135
d8ff3e95
JK
2136(F) You used the obsolete C<dump()> built-in function. That was deprecated in
2137Perl 5.8.0. As of Perl 5.30 it must be written in fully qualified format:
2138C<CORE::dump()>.
30b17cc1
A
2139
2140See L<perlfunc/dump>.
ac206dc8 2141
84d78eb7
YO
2142=item dump is not supported
2143
2144(F) Your machine doesn't support dump/undump.
2145
a0d0e21e
LW
2146=item Duplicate free() ignored
2147
be771a83
GS
2148(S malloc) An internal routine called free() on something that had
2149already been freed.
a0d0e21e 2150
1109a392
MHM
2151=item Duplicate modifier '%c' after '%c' in %s
2152
35f0cd76
FC
2153(W unpack) You have applied the same modifier more than once after a
2154type in a pack template. See L<perlfunc/pack>.
1109a392 2155
4633a7c4
LW
2156=item elseif should be elsif
2157
fa816bf3
FC
2158(S syntax) There is no keyword "elseif" in Perl because Larry thinks
2159it's ugly. Your code will be interpreted as an attempt to call a method
2160named "elseif" for the class returned by the following block. This is
4633a7c4
LW
2161unlikely to be what you want.
2162
c30c479a
KW
2163=item Empty \%c in regex; marked by S<<-- HERE> in m/%s/
2164
ccad8842
KW
2165=item Empty \%c{}
2166
e0e4a6e3 2167=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 2168
e750debb
KW
2169(F) You used something like C<\b{}>, C<\B{}>, C<\o{}>, C<\p>, C<\P>, or
2170C<\x> without specifying anything for it to operate on.
2171
2172Unfortunately, for backwards compatibility reasons, an empty C<\x> is
2173legal outside S<C<use re 'strict'>> and expands to a NUL character.
ab13f0c7 2174
d9a91485
KW
2175=item Empty (?) without any modifiers in regex; marked by <-- HERE in m/%s/
2176
2177(W regexp) (only under C<S<use re 'strict'>>)
2178C<(?)> does nothing, so perhaps this is a typo.
2179
fd503f5c 2180=item ${^ENCODING} is no longer supported
a15a3d9b 2181
fd503f5c 2182(F) The special variable C<${^ENCODING}>, formerly used to implement
a15a3d9b
FC
2183the C<encoding> pragma, is no longer supported as of Perl 5.26.0.
2184
fd503f5c
DIM
2185Setting it to anything other than C<undef> is a fatal error as of Perl
21865.28.
ac641426 2187
85ab1d1d 2188=item entering effective %s failed
5ff3f7a4 2189
85ab1d1d 2190(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2191effective uids or gids failed.
2192
c038024b
RGS
2193=item %ENV is aliased to %s
2194
2195(F) You're running under taint mode, and the C<%ENV> variable has been
2196aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 2197program's environment. This is potentially insecure.
c038024b 2198
748a9306
LW
2199=item Error converting file specification %s
2200
5f05dabc 2201(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 2202specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
2203single form when it must operate on them directly. Either you've passed
2204an invalid file specification to Perl, or you've found a case the
2205conversion routines don't handle. Drat.
748a9306 2206
ad19ef22 2207=item Eval-group in insecure regular expression
e4d48cc9 2208
be771a83
GS
2209(F) Perl detected tainted data when trying to compile a regular
2210expression that contains the C<(?{ ... })> zero-width assertion, which
2211is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 2212
ad19ef22 2213=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 2214
be771a83
GS
2215(F) Perl tried to compile a regular expression containing the
2216C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
2217pattern contains interpolated values. Since that is a security risk,
2218it is not allowed. If you insist, you may still do this by using the
2219C<re 'eval'> pragma or by explicitly building the pattern from an
2220interpolated string at run time and using that in an eval(). See
2221L<perlre/(?{ code })>.
e4d48cc9 2222
ad19ef22 2223=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 2224
be771a83
GS
2225(F) A regular expression contained the C<(?{ ... })> zero-width
2226assertion, but that construct is only allowed when the C<use re 'eval'>
2227pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 2228
e0e4a6e3
FC
2229=item EVAL without pos change exceeded limit in regex; marked by
2230S<<-- HERE> in m/%s/
1a147d38
YO
2231
2232(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 2233any text. Restructure the pattern so that text is consumed.
1a147d38 2234
6e8a73f2 2235The S<<-- HERE> shows whereabouts in the regular expression the problem was
1a147d38
YO
2236discovered.
2237
fc36a67e
PP
2238=item Excessively long <> operator
2239
2240(F) The contents of a <> operator may not exceed the maximum size of a
2241Perl identifier. If you're just trying to glob a long list of
2242filenames, try using the glob() operator, or put the filenames into a
2243variable and glob that.
2244
ed9aa3b7
SG
2245=item exec? I'm not *that* kind of operating system
2246
822c8b4d
DIM
2247(F) The C<exec> function is not implemented on some systems, e.g.
2248Catamount. See L<perlport>.
ed9aa3b7 2249
c77da5ff 2250=item %sExecution of %s aborted due to compilation errors.
a0d0e21e
LW
2251
2252(F) The final summary message when a Perl compilation fails.
2253
0ffcbc25
FC
2254=item exists argument is not a HASH or ARRAY element or a subroutine
2255
4a0af295 2256(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
2257subroutine with an ampersand, such as:
2258
2259 $foo{$bar}
2260 $ref->{"susie"}[12]
2261 &do_something
2262
2263=item exists argument is not a subroutine name
2264
ccfc2567
FC
2265(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
2266and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 2267
a0d0e21e
LW
2268=item Exiting eval via %s
2269
be771a83
GS
2270(W exiting) You are exiting an eval by unconventional means, such as a
2271goto, or a loop control statement.
e476b1b5
GS
2272
2273=item Exiting format via %s
2274
9a2ff54b 2275(W exiting) You are exiting a format by unconventional means, such as a
be771a83 2276goto, or a loop control statement.
a0d0e21e 2277
0a753a76
PP
2278=item Exiting pseudo-block via %s
2279
be771a83
GS
2280(W exiting) You are exiting a rather special block construct (like a
2281sort block or subroutine) by unconventional means, such as a goto, or a
2282loop control statement. See L<perlfunc/sort>.
0a753a76 2283
a0d0e21e
LW
2284=item Exiting subroutine via %s
2285
be771a83
GS
2286(W exiting) You are exiting a subroutine by unconventional means, such
2287as a goto, or a loop control statement.
a0d0e21e
LW
2288
2289=item Exiting substitution via %s
2290
be771a83
GS
2291(W exiting) You are exiting a substitution by unconventional means, such
2292as a return, a goto, or a loop control statement.
a0d0e21e 2293
e0e4a6e3 2294=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 2295
675fa9ff 2296(F) You wrote something like
c608e803
KW
2297
2298 (?13
2299
2300to denote a capturing group of the form
2301L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
2302but omitted the C<")">.
2303
d8d1dede
KW
2304=item Expecting interpolated extended charclass in regex; marked by <--
2305HERE in m/%s/
c9ffefcc 2306
d8d1dede
KW
2307(F) It looked like you were attempting to interpolate an
2308already-compiled extended character class, like so:
c9ffefcc 2309
d8d1dede
KW
2310 my $thai_or_lao = qr/(?[ \p{Thai} + \p{Lao} ])/;
2311 ...
2312 qr/(?[ \p{Digit} & $thai_or_lao ])/;
c9ffefcc 2313
d8d1dede
KW
2314But the marked code isn't syntactically correct to be such an
2315interpolated class.
27350048 2316
baabe3fb 2317=item Experimental aliasing via reference not enabled
1f8155a2 2318
baabe3fb 2319(F) To do aliasing via references, you must first enable the feature:
1f8155a2 2320
baabe3fb
FC
2321 no warnings "experimental::refaliasing";
2322 use feature "refaliasing";
1f8155a2
FC
2323 \$x = \$y;
2324
74d1b2e4
FC
2325=item Experimental %s on scalar is now forbidden
2326
2327(F) An experimental feature added in Perl 5.14 allowed C<each>, C<keys>,
2328C<push>, C<pop>, C<shift>, C<splice>, C<unshift>, and C<values> to be called with a
2329scalar argument. This experiment is considered unsuccessful, and
2330has been removed. The C<postderef> feature may meet your needs better.
2331
30d9c59b
Z
2332=item Experimental subroutine signatures not enabled
2333
2334(F) To use subroutine signatures, you must first enable them:
2335
caa35032 2336 no warnings "experimental::signatures";
30d9c59b
Z
2337 use feature "signatures";
2338 sub foo ($left, $right) { ... }
2339
7b8d334a
GS
2340=item Explicit blessing to '' (assuming package main)
2341
be771a83
GS
2342(W misc) You are blessing a reference to a zero length string. This has
2343the effect of blessing the reference into the package main. This is
2344usually not what you want. Consider providing a default target package,
2345e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2346
6df41af2
GS
2347=item %s: Expression syntax
2348
be771a83
GS
2349(A) You've accidentally run your script through B<csh> instead of Perl.
2350Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2351
2352=item %s failed--call queue aborted
2353
3c10abe3
AG
2354(F) An untrapped exception was raised while executing a UNITCHECK,
2355CHECK, INIT, or END subroutine. Processing of the remainder of the
2356queue of such routines has been prematurely ended.
6df41af2 2357
e0d4aead 2358=item Failed to close in-place work file %s: %s
502aca56
TC
2359
2360(F) Closing an output file from in-place editing, as with the C<-i>
2361command-line switch, failed.
2362
e0e4a6e3 2363=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2364
98d31c73 2365(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2366character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2367in your false range is interpreted as a literal "-". In a C<(?[...])>
2368construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2369the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2370the problem was discovered. See L<perlre>.
73b437c8 2371
1b1ee2ef 2372=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2373
be771a83
GS
2374(P) An error peculiar to VMS. Something untoward happened in a VMS
2375system service or RTL routine; Perl's exit status should provide more
2376details. The filename in "at %s" and the line number in "line %d" tell
2377you which section of the Perl source code is distressed.
a0d0e21e
LW
2378
2379=item fcntl is not implemented
2380
2381(F) Your machine apparently doesn't implement fcntl(). What is this, a
2382PDP-11 or something?
2383
22846ab4
AB
2384=item FETCHSIZE returned a negative value
2385
2386(F) A tied array claimed to have a negative number of elements, which
2387is not possible.
2388
f337b084
TH
2389=item Field too wide in 'u' format in pack
2390
d8b5cc61 2391(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2392which can't encode values above 63. So there is no point in asking for
2393a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2394C<u63> as the format.
f337b084 2395
a0e213fc
A
2396=item File::Glob::glob() will disappear in perl 5.30. Use File::Glob::bsd_glob() instead.
2397
2398(D deprecated) C<< File::Glob >> has a function called C<< glob >>, which
2399just calls C<< bsd_glob >>. However, its prototype is different from the
2400prototype of C<< CORE::glob >>, and hence, C<< File::Glob::glob >> should
2401not be used.
2402
2403C<< File::Glob::glob() >> was deprecated in perl 5.8.0. A deprecation
2404message was issued from perl 5.26.0 onwards, and the function will
2405disappear in perl 5.30.0.
2406
2407Code using C<< File::Glob::glob() >> should call
2408C<< File::Glob::bsd_glob() >> instead.
2409
af8c498a 2410=item Filehandle %s opened only for input
a0d0e21e 2411
6c8d78fb
HS
2412(W io) You tried to write on a read-only filehandle. If you intended
2413it to be a read-write filehandle, you needed to open it with "+<" or
2414"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2415write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2416
af8c498a 2417=item Filehandle %s opened only for output
a0d0e21e 2418
6c8d78fb
HS
2419(W io) You tried to read from a filehandle opened only for writing, If
2420you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2421with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2422read from the file, use "<". See L<perlfunc/open>. Another possibility
2423is that you attempted to open filedescriptor 0 (also known as STDIN) for
2424output (maybe you closed STDIN earlier?).
97828cef
RGS
2425
2426=item Filehandle %s reopened as %s only for input
2427
2428(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2429as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2430previously.
2431
2432=item Filehandle STDIN reopened as %s only for output
2433
2434(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2435as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2436
2437=item Final $ should be \$ or $name
2438
2439(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2440a literal dollar sign, or was meant to introduce a variable name that
2441happens to be missing. So you have to put either the backslash or the
2442name.
a0d0e21e 2443
56e90b21
GS
2444=item flock() on closed filehandle %s
2445
be771a83 2446(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2447some time before now. Check your control flow. flock() operates on
be771a83
GS
2448filehandles. Are you attempting to call flock() on a dirhandle by the
2449same name?
56e90b21 2450
6df41af2
GS
2451=item Format not terminated
2452
2453(F) A format must be terminated by a line with a solitary dot. Perl got
2454to the end of your file without finding such a line.
2455
a0d0e21e
LW
2456=item Format %s redefined
2457
e476b1b5 2458(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2459
2460 {
271595cc 2461 no warnings 'redefine';
a0d0e21e
LW
2462 eval "format NAME =...";
2463 }
2464
a0d0e21e
LW
2465=item Found = in conditional, should be ==
2466
e476b1b5 2467(W syntax) You said
a0d0e21e
LW
2468
2469 if ($foo = 123)
2470
2471when you meant
2472
2473 if ($foo == 123)
2474
2475(or something like that).
2476
6df41af2
GS
2477=item %s found where operator expected
2478
56da5a46
RGS
2479(S syntax) The Perl lexer knows whether to expect a term or an operator.
2480If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2481operator, it gives you this warning. Usually it indicates that an
2482operator or delimiter was omitted, such as a semicolon.
6df41af2 2483
a0d0e21e
LW
2484=item gdbm store returned %d, errno %d, key "%s"
2485
2486(S) A warning from the GDBM_File extension that a store failed.
2487
2488=item gethostent not implemented
2489
2490(F) Your C library apparently doesn't implement gethostent(), probably
2491because if it did, it'd feel morally obligated to return every hostname
2492on the Internet.
2493
69282e91 2494=item get%sname() on closed socket %s
a0d0e21e 2495
be771a83
GS
2496(W closed) You tried to get a socket or peer socket name on a closed
2497socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2498
748a9306
LW
2499=item getpwnam returned invalid UIC %#o for user "%s"
2500
2501(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2502C<getpwnam> operator returned an invalid UIC.
2503
6df41af2
GS
2504=item getsockopt() on closed socket %s
2505
be771a83
GS
2506(W closed) You tried to get a socket option on a closed socket. Did you
2507forget to check the return value of your socket() call? See
6df41af2
GS
2508L<perlfunc/getsockopt>.
2509
0f539b13
BF
2510=item given is experimental
2511
7896dde7
Z
2512(S experimental::smartmatch) C<given> depends on smartmatch, which
2513is experimental, so its behavior may change or even be removed
2514in any future release of perl. See the explanation under
2515L<perlsyn/Experimental Details on given and when>.
0f539b13 2516
68567d27
FC
2517=item Global symbol "%s" requires explicit package name (did you forget to
2518declare "my %s"?)
6df41af2 2519
a4edf47d 2520(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2521that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2522declared beforehand using "our", or explicitly qualified to say
2523which package the global variable is in (using "::").
6df41af2 2524
e476b1b5
GS
2525=item glob failed (%s)
2526
5ead438e 2527(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2528for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2529pattern that caused the external program to fail and exit with a
be771a83 2530nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2531resulted in a coredump, this may also mean that your csh (C shell)
2532is broken. If so, you should change all of the csh-related variables
2533in config.sh: If you have tcsh, make the variables refer to it as
2534if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2535all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2536think csh is missing. In either case, after editing config.sh, run
75b44862 2537C<./Configure -S> and rebuild Perl.
e476b1b5 2538
a0d0e21e
LW
2539=item Glob not terminated
2540
2541(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2542a term, so it's looking for the corresponding right angle bracket, and
2543not finding it. Chances are you left some needed parentheses out
2544earlier in the line, and you really meant a "less than".
a0d0e21e 2545
b35b96b6
JH
2546=item gmtime(%f) failed
2547
2548(W overflow) You called C<gmtime> with a number that it could not handle:
2549too large, too small, or NaN. The returned value is C<undef>.
2550
bcd05b94 2551=item gmtime(%f) too large
8b56d6ff 2552
e9200be3 2553(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2554it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2555date. This warning is also triggered with NaN (the special
fc003d4b
MS
2556not-a-number value).
2557
bcd05b94 2558=item gmtime(%f) too small
fc003d4b 2559
e9200be3 2560(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2561it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2562
6df41af2 2563=item Got an error from DosAllocMem
a0d0e21e 2564
6df41af2
GS
2565(P) An error peculiar to OS/2. Most probably you're using an obsolete
2566version of Perl, and this should not happen anyway.
a0d0e21e
LW
2567
2568=item goto must have label
2569
2570(F) Unlike with "next" or "last", you're not allowed to goto an
2571unspecified destination. See L<perlfunc/goto>.
2572
6651ba0b
FC
2573=item Goto undefined subroutine%s
2574
2575(F) You tried to call a subroutine with C<goto &sub> syntax, but
2576the indicated subroutine hasn't been defined, or if it was, it
2577has since been undefined.
2578
6fbc9859 2579=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2580S<<-- HERE> in m/%s/
1f4f6bf1
YO
2581
2582(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2583they must start with a non-digit word character. A common cause of
2584this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2585
5a25739d
FC
2586=item ()-group starts with a count
2587
2588(F) A ()-group started with a count. A count is supposed to follow
2589something: a template character or a ()-group. See L<perlfunc/pack>.
2590
fe13d51d 2591=item %s had compilation errors.
6df41af2
GS
2592
2593(F) The final summary message when a C<perl -c> fails.
2594
a0d0e21e
LW
2595=item Had to create %s unexpectedly
2596
be771a83
GS
2597(S internal) A routine asked for a symbol from a symbol table that ought
2598to have existed already, but for some reason it didn't, and had to be
2599created on an emergency basis to prevent a core dump.
a0d0e21e 2600
6df41af2
GS
2601=item %s has too many errors
2602
2603(F) The parser has given up trying to parse the program after 10 errors.
2604Further error messages would likely be uninformative.
2605
61e61fbc
JH
2606=item Hexadecimal float: exponent overflow
2607
d8f2b442 2608(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2609than the floating point supports.
2610
2611=item Hexadecimal float: exponent underflow
2612
d8f2b442 2613(W overflow) The hexadecimal floating point has a smaller exponent
b6d9b423
JH
2614than the floating point supports. With the IEEE 754 floating point,
2615this may also mean that the subnormals (formerly known as denormals)
2616are being used, which may or may not be an error.
61e61fbc 2617
5488d373 2618=item Hexadecimal float: internal error (%s)
cf4f6003
JH
2619
2620(F) Something went horribly bad in hexadecimal float handling.
2621
61e61fbc
JH
2622=item Hexadecimal float: mantissa overflow
2623
2624(W overflow) The hexadecimal floating point literal had more bits in
2625the mantissa (the part between the 0x and the exponent, also known as
2626the fraction or the significand) than the floating point supports.
2627
40bca5ae
JH
2628=item Hexadecimal float: precision loss
2629
2630(W overflow) The hexadecimal floating point had internally more
2631digits than could be output. This can be caused by unsupported
2632long double formats, or by 64-bit integers not being available
2633(needed to retrieve the digits under some configurations).
2634
2635=item Hexadecimal float: unsupported long double format
2636
2637(F) You have configured Perl to use long doubles but
d8f2b442 2638the internals of the long double format are unknown;
40bca5ae
JH
2639therefore the hexadecimal float output is impossible.
2640
252aa082
JH
2641=item Hexadecimal number > 0xffffffff non-portable
2642
e476b1b5 2643(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2644(4294967295) and therefore non-portable between systems. See
2645L<perlport> for more on portability concerns.
252aa082 2646
8903cb82
PP
2647=item Identifier too long
2648
2649(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2650about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2651names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2652of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2653
e0e4a6e3
FC
2654=item Ignoring zero length \N{} in character class in regex; marked by
2655S<<-- HERE> in m/%s/
fc8cd66c 2656
f3ba6905 2657(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
0f44b2a5
FC
2658zero-length sequence. When such an escape is used in a character
2659class its behavior is not well defined. Check that the correct
2660escape has been used, and the correct charname handler is in scope.
fc8cd66c 2661
bcfb98ec 2662=item Illegal %s digit '%c' ignored
f675dbe5 2663
bcfb98ec
KW
2664(W digit) Here C<%s> is one of "binary", "octal", or "hex".
2665You may have tried to use a digit other than one that is legal for the
2666given type, such as only 0 and 1 for binary. For octals, this is raised
2667only if the illegal character is an '8' or '9'. For hex, 'A' - 'F' and
2668'a' - 'f' are legal.
2669Interpretation of the number stopped just before the offending digit or
2670character.
f675dbe5 2671
bcfb98ec 2672=item Illegal binary digit '%c'
a0d0e21e 2673
bcfb98ec 2674(F) You used a digit other than 0 or 1 in a binary number.
a0d0e21e 2675
6597eb22
FC
2676=item Illegal character after '_' in prototype for %s : %s
2677
e4d150f1
FC
2678(W illegalproto) An illegal character was found in a prototype
2679declaration. The '_' in a prototype must be followed by a ';',
2680indicating the rest of the parameters are optional, or one of '@'
2681or '%', since those two will accept 0 or more final parameters.
6597eb22 2682
b913d0b8
FC
2683=item Illegal character \%o (carriage return)
2684
2685(F) Perl normally treats carriage returns in the program text as
2686it would any other whitespace, which means you should never see
2687this error when Perl was built using standard options. For some
2688reason, your version of Perl appears to have been built without
2689this support. Talk to your Perl administrator.
2690
bb6b75cd 2691=item Illegal character following sigil in a subroutine signature
d3d9da4a
DM
2692
2693(F) A parameter in a subroutine signature contained an unexpected character
d4e5761f
FC
2694following the C<$>, C<@> or C<%> sigil character. Normally the sigil
2695should be followed by the variable name or C<=> etc. Perhaps you are
d3d9da4a
DM
2696trying use a prototype while in the scope of C<use feature 'signatures'>?
2697For example:
2698
2699 sub foo ($$) {} # legal - a prototype
2700
2701 use feature 'signatures;
2702 sub foo ($$) {} # illegal - was expecting a signature
2703 sub foo ($a, $b)
2704 :prototype($$) {} # legal
2705
2706
d37a9538
ST
2707=item Illegal character in prototype for %s : %s
2708
197afce1 2709(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2710Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2711Perhaps you were trying to write a subroutine signature but didn't enable
2712that feature first (C<use feature 'signatures'>), so your signature was
2713instead interpreted as a bad prototype.
d37a9538 2714
904d85c5
RGS
2715=item Illegal declaration of anonymous subroutine
2716
2717(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2718you must always specify a block of code. See L<perlsub>.
904d85c5 2719
8e742a20
MHM
2720=item Illegal declaration of subroutine %s
2721
6903afa2 2722(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2723
a0d0e21e
LW
2724=item Illegal division by zero
2725
be771a83
GS
2726(F) You tried to divide a number by 0. Either something was wrong in
2727your logic, or you need to put a conditional in to guard against
2728meaningless input.
a0d0e21e
LW
2729
2730=item Illegal modulus zero
2731
be771a83
GS
2732(F) You tried to divide a number by 0 to get the remainder. Most
2733numbers don't take to this kindly.
a0d0e21e 2734
6df41af2 2735=item Illegal number of bits in vec
399388f4 2736
6df41af2
GS
2737(F) The number of bits in vec() (the third argument) must be a power of
2738two from 1 to 32 (or 64, if your platform supports that).
399388f4 2739
283151b7 2740=item Illegal octal digit '%c'
a0d0e21e 2741
d1be9408 2742(F) You used an 8 or 9 in an octal number.
a0d0e21e 2743
ecc6274e
FC
2744=item Illegal operator following parameter in a subroutine signature
2745
2746(F) A parameter in a subroutine signature, was followed by something
2747other than C<=> introducing a default, C<,> or C<)>.
2748
2749 use feature 'signatures';
2750 sub foo ($=1) {} # legal
2751 sub foo ($a = 1) {} # legal
2752 sub foo ($a += 1) {} # illegal
2753 sub foo ($a == 1) {} # illegal
2754
e0e4a6e3 2755=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2756
675fa9ff 2757(F) You wrote something like
c608e803
KW
2758
2759 (?+foo)
2760
2761The C<"+"> is valid only when followed by digits, indicating a
2762capturing group. See
2763L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2764
375ed12a
JH
2765=item Illegal suidscript
2766
2767(F) The script run under suidperl was somehow illegal.
2768
fe13d51d 2769=item Illegal switch in PERL5OPT: -%c
6ff81951 2770
6df41af2 2771(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2772following switches: B<-[CDIMUdmtw]>.
6ff81951 2773
4003ea29
KW
2774=item Illegal user-defined property name
2775
2776(F) You specified a Unicode-like property name in a regular expression
2777pattern (using C<\p{}> or C<\P{}>) that Perl knows isn't an official
2778Unicode property, and was likely meant to be a user-defined property
2779name, but it can't be one of those, as they must begin with either C<In>
2780or C<Is>. Check the spelling. See also
2781L</Can't find Unicode property definition "%s">.
2782
6df41af2 2783=item Ill-formed CRTL environ value "%s"
81e118e0 2784
75b44862 2785(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2786internal environ array, and encountered an element without the C<=>
2787delimiter used to separate keys from values. The element is ignored.
09bef843 2788
6df41af2 2789=item Ill-formed message in prime_env_iter: |%s|
54310121 2790
be771a83
GS
2791(W internal) A warning peculiar to VMS. Perl tried to read a logical
2792name or CLI symbol definition when preparing to iterate over %ENV, and
2793didn't see the expected delimiter between key and value, so the line was
2794ignored.
54310121 2795
6df41af2 2796=item (in cleanup) %s
9607fc9c 2797
be771a83
GS
2798(W misc) This prefix usually indicates that a DESTROY() method raised
2799the indicated exception. Since destructors are usually called by the
2800system at arbitrary points during execution, and often a vast number of
2801times, the warning is issued only once for any number of failures that
2802would otherwise result in the same message being repeated.
6df41af2 2803
be771a83
GS
2804Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2805also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2806
e0e4a6e3
FC
2807=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2808in m/%s/
0d0b4b3b 2809
675fa9ff 2810(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2811expression inside the construct was completely empty, or if there are
2812too many or few operands for the number of operators. Perl is not smart
2813enough to give you a more precise indication as to what is wrong.
2814
6fbc9859
MH
2815=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2816parent '%s'
2c7d6b9c
RGS
2817
2818(F) The method resolution order (MRO) of the given class is not
2819C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2820documentation in L<mro> for more information.
2821
cdd6375d
MH
2822=item Indentation on line %d of here-doc doesn't match delimiter
2823
2824(F) You have an indented here-document where one or more of its lines
2825have whitespace at the beginning that does not match the closing
2826delimiter.
2827
2828For example, line 2 below is wrong because it does not have at least
28292 spaces, but lines 1 and 3 are fine because they have at least 2:
2830
2831 if ($something) {
2832 print <<~EOF;
2833 Line 1
2834 Line 2 not
2835 Line 3
2836 EOF
2837 }
2838
2839Note that tabs and spaces are compared strictly, meaning 1 tab will
2840not match 8 spaces.
2841
6a2ed79a 2842=item Infinite recursion in regex
1a147d38
YO
2843
2844(F) You used a pattern that references itself without consuming any input
6903afa2 2845text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2846either consume text or fail.
2847
714f94d1
FC
2848=item Infinite recursion via empty pattern
2849
2850(F) You tried to use the empty pattern inside of a regex code block,
2851for instance C</(?{ s!!! })/>, which resulted in re-executing
2852the same pattern, which is an infinite loop which is broken by
2853throwing an exception.
2854
f99042c8 2855=item Initialization of state variables in list currently forbidden
6dbe9451 2856
f99042c8
Z
2857(F) C<state> only permits initializing a single variable, specified
2858without parentheses. So C<state $a = 42> and C<state @a = qw(a b c)> are
2859allowed, but not C<state ($a) = 42> or C<(state $a) = 42>. To initialize
2860more than one C<state> variable, initialize them one at a time.
6dbe9451 2861
2186f873
FC
2862=item %%s[%s] in scalar context better written as $%s[%s]
2863
2864(W syntax) In scalar context, you've used an array index/value slice
2865(indicated by %) to select a single element of an array. Generally
2866it's better to ask for a scalar value (indicated by $). The difference
2867is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2868returns and when evaluating its argument, while C<%foo[&bar]> provides
2869a list context to its subscript, which can do weird things if you're
2870expecting only one subscript. When called in list context, it also
2871returns the index (what C<&bar> returns) in addition to the value.
2872
2873=item %%s{%s} in scalar context better written as $%s{%s}
2874
2875(W syntax) In scalar context, you've used a hash key/value slice
2876(indicated by %) to select a single element of a hash. Generally it's
2877better to ask for a scalar value (indicated by $). The difference
2878is that C<$foo{&bar}> always behaves like a scalar, both in the value
2879it returns and when evaluating its argument, while C<@foo{&bar}> and
2880provides a list context to its subscript, which can do weird things
2881if you're expecting only one subscript. When called in list context,
2882it also returns the key in addition to the value.
2883
a0d0e21e
LW
2884=item Insecure dependency in %s
2885
8b1a09fc 2886(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2887The tainting mechanism is turned on when you're running setuid or
2888setgid, or when you specify B<-T> to turn it on explicitly. The
2889tainting mechanism labels all data that's derived directly or indirectly
2890from the user, who is considered to be unworthy of your trust. If any
2891such data is used in a "dangerous" operation, you get this error. See
2892L<perlsec> for more information.
a0d0e21e
LW
2893
2894=item Insecure directory in %s
2895
be771a83
GS
2896(F) You can't use system(), exec(), or a piped open in a setuid or
2897setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2898the world. Also, the PATH must not contain any relative directory.
2899See L<perlsec>.
a0d0e21e 2900
62f468fc 2901=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2902
2903(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2904setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2905C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2906supplied (or potentially supplied) by the user. The script must set
2907the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2908
0e9be77f
DM
2909=item Insecure user-defined property %s
2910
2911(F) Perl detected tainted data when trying to compile a regular
2912expression that contains a call to a user-defined character property
2913function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2914See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2915
b9ef414d
FC
2916=item Integer overflow in format string for %s
2917
2918(F) The indexes and widths specified in the format string of C<printf()>
2919or C<sprintf()> are too large. The numbers must not overflow the size of
2920integers for your architecture.
2921
a7ae9550
GS
2922=item Integer overflow in %s number
2923
35928bc5 2924(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2925either as a literal or as an argument to hex() or oct() is too big for
2926your architecture, and has been converted to a floating point number.
2927On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2928representable without overflow is 0xFFFFFFFF, 037777777777, or
29290b11111111111111111111111111111111 respectively. Note that Perl
2930transparently promotes all numbers to a floating point representation
2931internally--subject to loss of precision errors in subsequent
2932operations.
bbce6d69 2933
fc89ca81
FC
2934=item Integer overflow in srand
2935
2936(S overflow) The number you have passed to srand is too big to fit
2937in your architecture's integer representation. The number has been
2938replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2939architectures). This means you may be getting less randomness than
2940you expect, because different random seeds above the maximum will
2941return the same sequence of random numbers.
2942
46314c13
JP
2943=item Integer overflow in version
2944
18da5252
FC
2945=item Integer overflow in version %d
2946
784d71ed
FC
2947(W overflow) Some portion of a version initialization is too large for
2948the size of integers for your architecture. This is not a warning
f084e84f 2949because there is no rational reason for a version to try and use an
784d71ed
FC
2950element larger than typically 2**32. This is usually caused by trying
2951to use some odd mathematical operation as a version, like 100/9.
46314c13 2952
e0e4a6e3 2953=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2954
2955(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2956The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2957discovered.
2958
748a9306
LW
2959=item Internal inconsistency in tracking vforks
2960
be771a83
GS
2961(S) A warning peculiar to VMS. Perl keeps track of the number of times
2962you've called C<fork> and C<exec>, to determine whether the current call
2963to C<exec> should affect the current script or a subprocess (see
2964L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2965Perl is making a guess and treating this C<exec> as a request to
2966terminate the Perl script and execute the specified command.
748a9306 2967
870978ae
FC
2968=item internal %<num>p might conflict with future printf extensions
2969
2970(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2971formatting follows a slightly different set of rules when called from
2972C or XS code. Specifically, formats consisting of digits followed
2973by "p" (e.g., "%7p") are reserved for future use. If you see this
2974message, then an XS module tried to call that routine with one such
2975reserved format.
2976
e0e4a6e3 2977=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2978
fa816bf3 2979(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2980S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2981discovered.
a0d0e21e 2982
6df41af2
GS
2983=item %s (...) interpreted as function
2984
75b44862 2985(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2986followed by parentheses turns into a function, with all the list
64977eb6 2987operators arguments found inside the parentheses. See
13a2d996 2988L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2989
f51551f7
FC
2990=item In '(?...)', the '(' and '?' must be adjacent in regex;
2991marked by S<<-- HERE> in m/%s/
2992
2993(F) The two-character sequence C<"(?"> in this context in a regular
2994expression pattern should be an indivisible token, with nothing
2995intervening between the C<"("> and the C<"?">, but you separated them
2996with whitespace.
2997
d9790612 2998=item In '(*...)', the '(' and '*' must be adjacent in regex;
edf23316
FC
2999marked by S<<-- HERE> in m/%s/
3000
d9790612 3001(F) The two-character sequence C<"(*"> in this context in a regular
edf23316 3002expression pattern should be an indivisible token, with nothing
d9790612
KW
3003intervening between the C<"("> and the C<"*">, but you separated them.
3004Fix the pattern and retry.
edf23316 3005
09bef843
SB
3006=item Invalid %s attribute: %s
3007
a4a4c9e2 3008(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
3009by Perl or by a user-supplied handler. See L<attributes>.
3010
3011=item Invalid %s attributes: %s
3012
a4a4c9e2 3013(F) The indicated attributes for a subroutine or variable were not
be771a83 3014recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 3015
e0e4a6e3
FC
3016=item Invalid character in charnames alias definition; marked by
3017S<<-- HERE> in '%s
225fb84f
KW
3018
3019(F) You tried to create a custom alias for a character name, with
3020the C<:alias> option to C<use charnames> and the specified character in
3021the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
3022
c8028aa6
TC
3023=item Invalid \0 character in %s for %s: %s\0%s
3024
fa3234e3
FC
3025(W syscalls) Embedded \0 characters in pathnames or other system call
3026arguments produce a warning as of 5.20. The parts after the \0 were
3027formerly ignored by system calls.
c8028aa6 3028
e0e4a6e3 3029=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
3030
3031(F) Only certain characters are valid for character names. The
3032indicated one isn't. See L<charnames/CUSTOM ALIASES>.
3033
c635e13b
PP
3034=item Invalid conversion in %s: "%s"
3035
be771a83
GS
3036(W printf) Perl does not understand the given format conversion. See
3037L<perlfunc/sprintf>.
c635e13b 3038
e0e4a6e3
FC
3039=item Invalid escape in the specified encoding in regex; marked by
3040S<<-- HERE> in m/%s/
9e08bc66 3041
98d31c73 3042(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
3043didn't correspond to a single character through the conversion
3044from the encoding specified by the encoding pragma.
98d31c73
FC
3045The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
3046instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 3047The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
3048escape was discovered.
3049
8149aa9f
FC
3050=item Invalid hexadecimal number in \N{U+...}
3051
e0e4a6e3
FC
3052=item Invalid hexadecimal number in \N{U+...} in regex; marked by
3053S<<-- HERE> in m/%s/
aec0ef10 3054
8149aa9f 3055(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
3056number. Either it is empty, or you tried to use a character other than
30570 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 3058
6651ba0b
FC
3059=item Invalid module name %s with -%c option: contains single ':'
3060
3061(F) The module argument to perl's B<-m> and B<-M> command-line options
3062cannot contain single colons in the module name, but only in the
3063arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
3064B<-MFoo:Bar=baz> is not.
3065
2c7d6b9c
RGS
3066=item Invalid mro name: '%s'
3067
162a3e34
FC
3068(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
3069where C<foo> is not a valid method resolution order (MRO). Currently,
3070the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
3071a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 3072
40e4140b
FC
3073=item Invalid negative number (%s) in chr
3074
3075(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 3076not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
3077character (U+FFFD).
3078
74d1b2e4
FC
3079=item Invalid number '%s' for -C option.
3080
3081(F) You supplied a number to the -C option that either has extra leading
3082zeroes or overflows perl's unsigned integer representation.
3083
6651ba0b
FC
3084=item invalid option -D%c, use -D'' to see choices
3085
8ff21bfe
FC
3086(S debugging) Perl was called with invalid debugger flags. Call perl
3087with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 3088See also L<perlrun/-Dletters>.
6651ba0b 3089
6e8a73f2 3090=item Invalid quantifier in {,} in regex; marked by S<<-- HERE> in m/%s/
35cd12d1
HS
3091
3092(F) The pattern looks like a {min,max} quantifier, but the min or max
3093could not be parsed as a valid number - either it has leading zeroes,
3094or it represents too big a number to cope with. The S<<-- HERE> shows
3095where in the regular expression the problem was discovered. See L<perlre>.
3096
e0e4a6e3 3097=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
3098
3099(F) The range specified in a character class had a minimum character
7253e4e3
RK
3100greater than the maximum character. One possibility is that you forgot the
3101C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 3102up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 3103problem was discovered. See L<perlre>.
6df41af2 3104
d1573ac7 3105=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
3106
3107(F) The range specified in the tr/// or y/// operator had a minimum
3108character greater than the maximum character. See L<perlop>.
3109
daa74010
KW
3110=item Invalid reference to group in regex; marked by S<<-- HERE> in m/%s/
3111
3112(F) The capture group you specified can't possibly exist because the
3113number you used is not within the legal range of possible values for
3114this machine.
3115
09bef843
SB
3116=item Invalid separator character %s in attribute list
3117
0120eecf 3118(F) Something other than a colon or whitespace was seen between the
be771a83
GS
3119elements of an attribute list. If the previous attribute had a
3120parenthesised parameter list, perhaps that list was terminated too soon.
3121See L<attributes>.
09bef843 3122
b4581f09
JH
3123=item Invalid separator character %s in PerlIO layer specification %s
3124
2bfc5f71
FC
3125(W layer) When pushing layers onto the Perl I/O system, something other
3126than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
3127If the previous attribute had a parenthesised parameter list, perhaps that
3128list was terminated too soon.
3129
2c86d456
DG
3130=item Invalid strict version format (%s)
3131
fa816bf3 3132(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
3133A "strict" version number is a positive decimal number (integer or
3134decimal-fraction) without exponentiation or else a dotted-decimal
3135v-string with a leading 'v' character and at least three components.
a6485a24 3136The parenthesized text indicates which criteria were not met.
2c86d456
DG
3137See the L<version> module for more details on allowed version formats.
3138
49704364 3139=item Invalid type '%s' in %s
96e4d5b1 3140
49704364
LW
3141(F) The given character is not a valid pack or unpack type.
3142See L<perlfunc/pack>.
6728c851 3143
49704364 3144(W) The given character is not a valid pack or unpack type but used to be
75b44862 3145silently ignored.
96e4d5b1 3146
2c86d456
DG
3147=item Invalid version format (%s)
3148
fa816bf3 3149(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
3150A "lax" version number is a positive decimal number (integer or
3151decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
3152v-string. If the v-string has fewer than three components, it
3153must have a leading 'v' character. Otherwise, the leading 'v' is
3154optional. Both decimal and dotted-decimal versions may have a
3155trailing "alpha" component separated by an underscore character
3156after a fractional or dotted-decimal component. The parenthesized
3157text indicates which criteria were not met. See the L<version> module
3158for more details on allowed version formats.
46314c13 3159
798ae1b7
DG
3160=item Invalid version object
3161
fa816bf3
FC
3162(F) The internal structure of the version object was invalid.
3163Perhaps the internals were modified directly in some way or
3164an arbitrary reference was blessed into the "version" class.
798ae1b7 3165
cd209d9d 3166=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 3167marked by S<<-- HERE> in m/%s/
675fa9ff 3168
cc06e157
KW
3169=item Inverting a character class which contains a multi-character
3170sequence is illegal in regex; marked by <-- HERE in m/%s/
3171
3172(F) You wrote something like
3173
3174 qr/\P{name=KATAKANA LETTER AINU P}/
3175 qr/[^\p{name=KATAKANA LETTER AINU P}]/
3176
3177This name actually evaluates to a sequence of two Katakana characters,
3178not just a single one, and it is illegal to try to take the complement
3179of a sequence. (Mathematically it would mean any sequence of characters
3180from 0 to infinity in length that weren't these two in a row, and that
3181is likely not of any real use.)
3182
edf23316
FC
3183(F) The two-character sequence C<"(*"> in this context in a regular
3184expression pattern should be an indivisible token, with nothing
3185intervening between the C<"("> and the C<"*">, but you separated them.
675fa9ff 3186
a0d0e21e
LW
3187=item ioctl is not implemented
3188
3189(F) Your machine apparently doesn't implement ioctl(), which is pretty
3190strange for a machine that supports C.
3191
c289d2f7
JH
3192=item ioctl() on unopened %s
3193
3194(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 3195Check your control flow and number of arguments.
c289d2f7 3196
fe13d51d 3197=item IO layers (like '%s') unavailable
363c40c4
SB
3198
3199(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 3200you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
3201with 'useperlio'.
3202
80cbd5ad
JH
3203=item IO::Socket::atmark not implemented on this architecture
3204
3205(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 3206neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 3207
6e8a73f2 3208=item '%s' is an unknown bound type in regex; marked by S<<-- HERE> in m/%s/
64935bc6
KW
3209
3210(F) You used C<\b{...}> or C<\B{...}> and the C<...> is not known to
3211Perl. The current valid ones are given in
3212L<perlrebackslash/\b{}, \b, \B{}, \B>.
3213
ac3afc4b
YO
3214=item %s is forbidden - matches null string many times in regex; marked by S<<-- HERE> in
3215m/%s/
3216
3217(F) The pattern you've specified might cause the regular expression to
3218infinite loop so it is forbidden. The S<<-- HERE>
3219shows whereabouts in the regular expression the problem was discovered.
3220See L<perlre>.
3221
1ed4b776 3222=item %s() isn't allowed on :utf8 handles
74d1b2e4 3223
1ed4b776
TC
3224(F) The sysread(), recv(), syswrite() and send() operators are
3225not allowed on handles that have the C<:utf8> layer, either explicitly, or
74d1b2e4
FC
3226implicitly, eg., with the C<:encoding(UTF-16LE)> layer.
3227
1ed4b776
TC
3228Previously sysread() and recv() currently use only the C<:utf8> flag for the stream,
3229ignoring the actual layers. Since sysread() and recv() did no UTF-8
74d1b2e4
FC
3230validation they can end up creating invalidly encoded scalars.
3231
1ed4b776
TC
3232Similarly, syswrite() and send() used only the C<:utf8> flag, otherwise ignoring
3233any layers. If the flag is set, both wrote the value UTF-8 encoded, even if
74d1b2e4
FC
3234the layer is some different encoding, such as the example above.
3235
3236Ideally, all of these operators would completely ignore the C<:utf8> state,
3237working only with bytes, but this would result in silently breaking existing
1972ac5c
A
3238code.
3239
d4360efa 3240=item "%s" is more clearly written simply as "%s" in regex; marked by S<<-- HERE> in m/%s/
acdfc3b6 3241
d4360efa 3242(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
30b17cc1 3243
3f673807
FC
3244You specified a character that has the given plainer way of writing it, and
3245which is also portable to platforms running with different character sets.
acdfc3b6 3246
dcb414ac 3247=item $* is no longer supported as of Perl 5.30
a678626e 3248
dcb414ac
JK
3249(F) The special variable C<$*>, deprecated in older perls, was removed in
32505.10.0, is no longer supported and is a fatal error as of Perl 5.30. In
a678626e
A
3251previous versions of perl the use of C<$*> enabled or disabled multi-line
3252matching within a string.
3253
3254Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
3255modifiers. You can enable C</m> for a lexical scope (even a whole file)
3256with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
3257then all regular expressions behaved as if they were written using C</m>.)
3258
37398dc1
A
3259Use of this variable will be a fatal error in Perl 5.30.
3260
dcb414ac 3261=item $# is no longer supported as of Perl 5.30
a678626e 3262
dcb414ac
JK
3263(F) The special variable C<$#>, deprecated in older perls, was removed as of
32645.10.0, is no longer supported and is a fatal error as of Perl 5.30. You
a678626e
A
3265should use the printf/sprintf functions instead.
3266
ccf3535a 3267=item '%s' is not a code reference
6ad11d81 3268
6903afa2
FC
3269(W overload) The second (fourth, sixth, ...) argument of
3270overload::constant needs to be a code reference. Either
3271an anonymous subroutine, or a reference to a subroutine.
6ad11d81 3272
ccf3535a 3273=item '%s' is not an overloadable type
6ad11d81 3274
04a80ee0
RGS
3275(W overload) You tried to overload a constant type the overload package is
3276unaware of.
6ad11d81 3277
813e85a0
PLE
3278=item isa is experimental
3279
3280(S experimental::isa) This warning is emitted if you use the (C<isa>)
3281operator. This operator is currently experimental and its behaviour may
3282change in future releases of Perl.
3283
5a25739d
FC
3284=item -i used with no filenames on the command line, reading from STDIN
3285
3286(S inplace) The C<-i> option was passed on the command line, indicating
3287that the script is intended to edit files in place, but no files were
3288given. This is usually a mistake, since editing STDIN in place doesn't
3289make sense, and can be confusing because it can make perl look like
3290it is hanging when it is really just trying to read from STDIN. You
3291should either pass a filename to edit, or remove C<-i> from the command
028611fa 3292line. See L<perlrun|perlrun/-i[extension]> for more details.
5a25739d 3293
aec0ef10 3294=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
3295
3296(P) The regular expression parser is confused.
3297
105c827d
TC
3298=item \K not permitted in lookahead/lookbehind in regex; marked by <-- HERE in m/%s/
3299
64a5950a 3300(F) Your regular expression used C<\K> in a lookahead or lookbehind
55afc783
TC
3301assertion, which currently isn't permitted.
3302
3303This may change in the future, see L<Support \K in
3304lookarounds|https://github.com/Perl/perl5/issues/18134>.
105c827d 3305
a0d0e21e
LW
3306=item Label not found for "last %s"
3307
be771a83
GS
3308(F) You named a loop to break out of, but you're not currently in a loop
3309of that name, not even if you count where you were called from. See
3310L<perlfunc/last>.
a0d0e21e
LW
3311
3312=item Label not found for "next %s"
3313
3314(F) You named a loop to continue, but you're not currently in a loop of
3315that name, not even if you count where you were called from. See
3316L<perlfunc/last>.
3317
3318=item Label not found for "redo %s"
3319
3320(F) You named a loop to restart, but you're not currently in a loop of
3321that name, not even if you count where you were called from. See
3322L<perlfunc/last>.
3323
85ab1d1d 3324=item leaving effective %s failed
5ff3f7a4 3325
85ab1d1d 3326(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
3327effective uids or gids failed.
3328
49704364
LW
3329=item length/code after end of string in unpack
3330
d7f8936a 3331(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
3332length/code combination tried to obtain more data. This results in
3333an undefined value for the length. See L<perlfunc/pack>.
49704364 3334
25e26107 3335=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 3336
0d46a4e7
FC
3337(W syntax) You used length() on either an array or a hash when you
3338probably wanted a count of the items.
e508c8a4
MH
3339
3340Array size can be obtained by doing:
3341
3342 scalar(@array);
3343
3344The number of items in a hash can be obtained by doing:
3345
3346 scalar(keys %hash);
3347
f0e67a1d
Z
3348=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
3349
d4fe7078
RS
3350(F) An extension is attempting to insert text into the current parse
3351(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
3352couldn't be part of the current input. This is an inherent pitfall
3353of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 3354it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
3355
3356=item Lexing code internal error (%s)
3357
3358(F) Lexing code supplied by an extension violated the lexer's API in a
3359detectable way.
3360
69282e91 3361=item listen() on closed socket %s
a0d0e21e 3362
be771a83
GS
3363(W closed) You tried to do a listen on a closed socket. Did you forget
3364to check the return value of your socket() call? See
3365L<perlfunc/listen>.
a0d0e21e 3366
6651ba0b
FC
3367=item List form of piped open not implemented
3368
3369(F) On some platforms, notably Windows, the three-or-more-arguments
3370form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
3371Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
3372
2a6971a9
KW
3373=item Literal vertical space in [] is illegal except under /x in regex;
3374marked by S<<-- HERE> in m/%s/
3375
3376(F) (only under C<S<use re 'strict'>> or within C<(?[...])>)
3377
3378Likely you forgot the C</x> modifier or there was a typo in the pattern.
3379For example, did you really mean to match a form-feed? If so, all the
3380ASCII vertical space control characters are representable by escape
3381sequences which won't p