gistfile1.txt

my @initial = (1..15).List.pick(15);
use NativeCall;
sub malloc(size_t --> Pointer) is native { * };
sub memcpy_A(Buf, Pointer, size_t) is native is symbol("memcpy") { };
sub memcpy_B(Pointer, Buf, size_t) is native is symbol("memcpy") { };

sub qsort(Pointer, size_t, size_t, &compar (Pointer, Pointer --> Pointer)) is native { * };

my $data = Buf[uint8].new(@initial);
my $ptr = malloc(15);

memcpy_B($ptr, $data, 15);
say [$ptr, $data];

qsort $ptr, 15, 1, -> Pointer $first, Pointer $second --> Pointer {
    Pointer.new(nativecast(uint8, $first) - nativecast(uint8, $second))
};

memcpy_A($data, $ptr, 15);
say [$ptr, $data]; # this works