Fix warnings

This change fixes Cosmopolitan so it has fewer opinions about compiler
warnings. The whole repository had to be cleaned up to be buildable in
-Werror -Wall mode. This lets us benefit from things like strict const
checking. Some actual bugs might have been caught too.

third_party/nsync/futex.c

@@ -163,9 +163,8 @@ static int nsync_futex_polyfill_ (atomic_int *w, int expect, struct timespec *ab
 	return -ETIMEDOUT;
 }
 
-static int nsync_futex_wait_win32_ (atomic_int *w, int expect, char pshare, struct timespec *timeout) {
+static int nsync_futex_wait_win32_ (atomic_int *w, int expect, char pshare, const struct timespec *timeout) {
 	int rc;
-	uint32_t ms;
 	struct timespec deadline, interval, remain, wait, now;
 
 	if (timeout) {
@@ -211,8 +210,8 @@ static struct timespec *nsync_futex_timeout_ (struct timespec *memory,
 	}
 }
 
-int nsync_futex_wait_ (atomic_int *w, int expect, char pshare, struct timespec *abstime) {
-	int e, rc, op, fop;
+int nsync_futex_wait_ (atomic_int *w, int expect, char pshare, const struct timespec *abstime) {
+	int e, rc, op;
 	struct PosixThread *pt = 0;
 	struct timespec tsmem, *timeout;
 
@@ -298,7 +297,7 @@ Finished:
 }
 
 int nsync_futex_wake_ (atomic_int *w, int count, char pshare) {
-	int e, rc, op, fop;
+	int rc, op, fop;
 
 	ASSERT (count == 1 || count == INT_MAX);
 

third_party/nsync/futex.internal.h

@@ -6,7 +6,7 @@
 COSMOPOLITAN_C_START_
 
 int nsync_futex_wake_(_Atomic(int) *, int, char);
-int nsync_futex_wait_(_Atomic(int) *, int, char, struct timespec *);
+int nsync_futex_wait_(_Atomic(int) *, int, char, const struct timespec *);
 
 COSMOPOLITAN_C_END_
 #endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */

third_party/nsync/mu_semaphore_futex.c

@@ -52,7 +52,7 @@ void nsync_mu_semaphore_init_futex (nsync_semaphore *s) {
 /* Wait until the count of *s exceeds 0, and decrement it. */
 errno_t nsync_mu_semaphore_p_futex (nsync_semaphore *s) {
 	struct futex *f = (struct futex *) s;
-	int e, i;
+	int i;
 	errno_t result = 0;
 	do {
 		i = ATM_LOAD ((nsync_atomic_uint32_ *) &f->i);
@@ -79,7 +79,7 @@ errno_t nsync_mu_semaphore_p_futex (nsync_semaphore *s) {
    or abs_deadline expires, in which case return ETIMEDOUT. */
 errno_t nsync_mu_semaphore_p_with_deadline_futex (nsync_semaphore *s, nsync_time abs_deadline) {
 	struct futex *f = (struct futex *)s;
-	int e, i;
+	int i;
 	int result = 0;
 	do {
 		i = ATM_LOAD ((nsync_atomic_uint32_ *) &f->i);

third_party/nsync/mu_semaphore_gcd.c

@@ -50,6 +50,7 @@ static long dispatch_semaphore_wait (dispatch_semaphore_t ds,
 
 static long dispatch_semaphore_signal (dispatch_semaphore_t ds) {
 	long rc = __syslib->dispatch_semaphore_signal (ds);
+	(void)rc;
 	STRACE ("dispatch_semaphore_signal(%#lx) → %ld", ds, rc);
 	return (ds);
 }