+(W) This prefix usually indicates that a DESTROY() method raised
+the indicated exception. Since destructors are usually called by
+the system at arbitrary points during execution, and often a vast
+number of times, the warning is issued only once for any number
+of failures that would otherwise result in the same message being
+repeated.
+
+Failure of user callbacks dispatched using the C<G_KEEPERR> flag
+could also result in this warning. See L<perlcall/G_KEEPERR>.
+
+=item <> should be quotes
+
+(F) You wrote C<require E<lt>fileE<gt>> when you should have written
+C<require 'file'>.
+
+=item Attempt to join self
+
+(F) You tried to join a thread from within itself, which is an
+impossible task. You may be joining the wrong thread, or you may
+need to move the join() to some other thread.
+
+=item Bad evalled substitution pattern
+
+(F) You've used the /e switch to evaluate the replacement for a
+substitution, but perl found a syntax error in the code to evaluate,
+most likely an unexpected right brace '}'.
+
+=item Bad realloc() ignored
+
+(S) An internal routine called realloc() on something that had never been
+malloc()ed in the first place. Mandatory, but can be disabled by
+setting environment variable C<PERL_BADFREE> to 1.
+
+=item Binary number > 0b11111111111111111111111111111111 non-portable
+
+(W) The binary number you specified is larger than 2**32-1
+(4294967295) and therefore non-portable between systems. See
+L<perlport> for more on portability concerns.
+
+=item Bit vector size > 32 non-portable
+
+(W) Using bit vector sizes larger than 32 is non-portable.
+
+=item Buffer overflow in prime_env_iter: %s
+
+(W) A warning peculiar to VMS. While Perl was preparing to iterate over
+%ENV, it encountered a logical name or symbol definition which was too long,
+so it was truncated to the string shown.
+
+=item Can't check filesystem of script "%s"
+
+(P) For some reason you can't check the filesystem of the script for nosuid.
+
+=item Can't ignore signal CHLD, forcing to default
+
+(W) Perl has detected that it is being run with the SIGCHLD signal
+(sometimes known as SIGCLD) disabled. Since disabling this signal
+will interfere with proper determination of exit status of child
+processes, Perl has reset the signal to its default value.
+This situation typically indicates that the parent program under
+which Perl may be running (e.g. cron) is being very careless.
+
+=item Can't modify non-lvalue subroutine call
+
+(F) Subroutines meant to be used in lvalue context should be declared as
+such, see L<perlsub/"Lvalue subroutines">.
+
+=item Can't read CRTL environ
+
+(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
+from the CRTL's internal environment array and discovered the array was
+missing. You need to figure out where your CRTL misplaced its environ
+or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not searched.
+
+=item Can't remove %s: %s, skipping file
+
+(S) You requested an inplace edit without creating a backup file. Perl
+was unable to remove the original file to replace it with the modified
+file. The file was left unmodified.
+
+=item Can't return %s from lvalue subroutine
+
+(F) Perl detected an attempt to return illegal lvalues (such
+as temporary or readonly values) from a subroutine used as an lvalue.
+This is not allowed.
+
+=item Can't weaken a nonreference
+
+(F) You attempted to weaken something that was not a reference. Only
+references can be weakened.
+
+=item Character class [:%s:] unknown
+
+(F) The class in the character class [: :] syntax is unknown.
+See L<perlre>.
+
+=item Character class syntax [%s] belongs inside character classes
+
+(W) The character class constructs [: :], [= =], and [. .] go
+I<inside> character classes, the [] are part of the construct,
+for example: /[012[:alpha:]345]/. Note that [= =] and [. .]
+are not currently implemented; they are simply placeholders for
+future extensions.
+
+=item Constant is not %s reference
+
+(F) A constant value (perhaps declared using the C<use constant> pragma)
+is being dereferenced, but it amounts to the wrong type of reference. The
+message indicates the type of reference that was expected. This usually
+indicates a syntax error in dereferencing the constant value.
+See L<perlsub/"Constant Functions"> and L<constant>.
+
+=item constant(%s): %%^H is not localized
+
+(F) When setting compile-time-lexicalized hash %^H one should set the
+corresponding bit of $^H as well.
+
+=item constant(%s): %s
+
+(F) Compile-time-substitutions (such as overloaded constants and
+character names) were not correctly set up.
+
+=item defined(@array) is deprecated
+
+(D) defined() is not usually useful on arrays because it checks for an
+undefined I<scalar> value. If you want to see if the array is empty,
+just use C<if (@array) { # not empty }> for example.
+
+=item defined(%hash) is deprecated
+
+(D) defined() is not usually useful on hashes because it checks for an
+undefined I<scalar> value. If you want to see if the hash is empty,
+just use C<if (%hash) { # not empty }> for example.
+
+=item Did not produce a valid header
+
+See Server error.
+
+=item Document contains no data
+
+See Server error.
+
+=item entering effective %s failed
+
+(F) While under the C<use filetest> pragma, switching the real and
+effective uids or gids failed.
+
+=item false [] range "%s" in regexp
+
+(W) A character class range must start and end at a literal character, not
+another character class like C<\d> or C<[:alpha:]>. The "-" in your false
+range is interpreted as a literal "-". Consider quoting the "-", "\-".
+See L<perlre>.