use strict;
use warnings;

use Devel::Peek qw( Dump );

use Inline C => <<'__EOI__';

void buggy_assign(SV* dsv, SV* ssv) {
   SvSetSV_nosteal(dsv, ssv);
   /* Should call SvSetMagicSV_nosteal(dsv, ssv); instead
    * or should call SvSETMAGIC(dsv); afterwards.
    */
}

void set_magic(SV* sv) {
   SvSETMAGIC(sv);
}

__EOI__

my $txt_de = "K\N{U+00E4}se";
my $txt_ru = "\N{U+041C}\N{U+043E}\N{U+0441}\N{U+043A}\N{U+0432}\N{U+0430}";

# \N should have done this already.
utf8::upgrade($_) for $txt_de, $txt_ru;

my $txt;

buggy_assign($txt, $txt_de);
print(length($txt), "\n"); Dump($txt);

buggy_assign($txt, $txt_ru);
print(length($txt), "\n"); Dump($txt);

set_magic($txt);
print(length($txt), "\n"); Dump($txt);