fix wrong return value from wmemmove on forward copies

[musl] / src / string / memcmp.c

#include <string.h>

int memcmp(const void *vl, const void *vr, size_t n)
{
        const unsigned char *l=vl, *r=vr;
        for (; n && *l == *r; n--, l++, r++);
        return n ? *l-*r : 0;
}