(F) You tried to unshift an "unreal" array that can't be unshifted, such
as the main Perl stack.
-=item Can't upgrade that kind of scalar
+=item Can't upgrade %s (%d) to %d
(P) The internal sv_upgrade routine adds "members" to an SV, making it
into a more specialized kind of SV. The top several SV types are so
specialized, however, that they cannot be interconverted. This message
indicates that such a conversion was attempted.
-=item Can't upgrade to undef
-
-(P) The undefined SV is the bottom of the totem pole, in the scheme of
-upgradability. Upgrading to undef indicates an error in the code
-calling sv_upgrade.
-
=item Can't use anonymous symbol table for method lookup
(F) The internal routine that does method lookup was handed a symbol
(W misc) You used the obsolescent C<dump()> built-in function, without fully
qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
+=item dump is not supported
+
+(F) Your machine doesn't support dump/undump.
+
=item Duplicate free() ignored
(S malloc) An internal routine called free() on something that had
=item Integer overflow in format string for %s
-(F) The indexes and widths specified in the format string of printf()
-or sprintf() are too large. The numbers must not overflow the size of
+(F) The indexes and widths specified in the format string of C<printf()>
+or C<sprintf()> are too large. The numbers must not overflow the size of
integers for your architecture.
=item Integer overflow in version
(P) The internal do_trans routines were called with invalid operational
data.
+=item panic: fold_constants JMPENV_PUSH returned %d
+
+(P) While attemtping folding constants an exception other than an C<eval>
+failure was caught.
+
=item panic: frexp
(P) The library function frexp() failed, making printf("%f") impossible.
=item The 'unique' attribute may only be applied to 'our' variables
-(F) Currently this attribute is not supported on C<my> or C<sub>
-declarations. See L<perlfunc/our>.
+(F) This attribute was never supported on C<my> or C<sub> declarations.
=item This Perl can't reset CRTL environ elements (%s)
=item Version string '%s' contains invalid data; ignoring: '%s'
-(W misc) The version string contains invalid characters, so it is
-being ignored.
+(W misc) The version string contains invalid characters at the end, which
+are being ignored.
=item v-string in use/require is non-portable