musl/src/signal/siglongjmp.c

#include <setjmp.h>
#include <signal.h>
#include <stdlib.h>
#include "syscall.h"

_Noreturn void siglongjmp(sigjmp_buf buf, int ret)
{
	if (buf->__fl) __syscall(SYS_rt_sigprocmask, SIG_SETMASK,
		buf->__ss, 0, __SYSCALL_SSLEN);
	longjmp(buf->__jb, ret);
}