fix buffer overrun in getgrent code when there are no group members

[musl] / src / thread / pthread_mutexattr_getpshared.c

#include "pthread_impl.h"

int pthread_mutexattr_getpshared(const pthread_mutexattr_t *a, int *pshared)
{
        *pshared = *a>>31;
        return 0;
}