acos.s fix: use the formula acos(x) = atan2(sqrt(1-x),sqrt(1+x))

[musl] / src / thread / pthread_attr_setstacksize.c

#include "pthread_impl.h"

int pthread_attr_setstacksize(pthread_attr_t *a, size_t size)
{
        if (size-PTHREAD_STACK_MIN > SIZE_MAX/4) return EINVAL;
        a->_a_stacksize = size - DEFAULT_STACK_SIZE;
        return 0;
}