Re^3: Memory Leak with XS but not pure C

The standard Perl uc just leaves it there when uppercasing.

Any currently supported perl should uppercase it correctly:

$ cat uct.pl 
#!/usr/bin/env perl
use strict;
use warnings;
use utf8;

my $string = 'straße';
my $ucstring = uc $string;
print "Uppercase $string is $ucstring\n";
$ perl uct.pl 
Uppercase straße is STRASSE
$

Are you running an old version?

🦛

Comment on Re^3: Memory Leak with XS but not pure C

Replies are listed 'Best First'.
Re^4: Memory Leak with XS but not pure C by ikegami (Patriarch) on Mar 29, 2025 at 17:15 UTC
`uc` suffers from The Unicode Bug when the `unicode_strings` feature isn't in enabled. It works correctly (giving `SS` for `ß`) when the string the `unicode_strings` feature is enabled. It works correctly (giving `SS` for `ß`) when the string is stored in the UTF8=1 format. It works incorrectly (`ß` unchanged) otherwise. `use open ":std", ":locale"; use feature qw( say ); my $ss = "\xDF"; utf8::upgrade( my $ss_u = $ss ); utf8::downgrade( my $ss_d = $ss ); { no feature qw( unicode_strings ); say uc( $ss_d ); # ß say uc( $ss_u ); # SS } { use feature qw( unicode_strings ); say uc( $ss_d ); # SS say uc( $ss_u ); # SS }` [download]	[reply] [d/l] [select]
Re^5: Memory Leak with XS but not pure C by FrankFooty (Novice) on Mar 31, 2025 at 10:21 UTC
Thanks very much Ikegami. I hadn't heard of that feature How is it possible to get the same behaviour within an XS function	[reply]
Re^6: Memory Leak with XS but not pure C by syphilis (Archbishop) on Mar 31, 2025 at 12:29 UTC
How is it possible to get the same behaviour within an XS function There is https://perldoc.perl.org/perlapi#Character-case-changing . (Maybe other places, too ... but that's the only link I could find quickly.) Cheers, Rob	[reply]
Re^6: Memory Leak with XS but not pure C by ikegami (Patriarch) on Mar 31, 2025 at 13:20 UTC
If you're asking how to convert to uppercase from XS, you'd start with an upgraded string, then call `toUPPER_uvchr` or `toUPPER_utf8` repeatedly. (Or call a Perl function that uses `uc`.)	[reply] [d/l] [select]
Re^6: Memory Leak with XS but not pure C by ikegami (Patriarch) on Mar 31, 2025 at 13:18 UTC
There is nothing that can affect the behaviour of Perl's `uc` operator in XS code. But you can't use Perl operators in C/XS code anyway.	[reply] [d/l]