--- Libc/Libc-825.26/stdlib/FreeBSD/psort.c
+++ Libc/Libc-1669.40.2/stdlib/FreeBSD/psort.c
@@ -42,8 +42,11 @@
 #include <libkern/OSAtomic.h>
 #include <sys/mman.h>
 #include <errno.h>
+#include <os/lock.h>
 #define __APPLE_API_PRIVATE
 #include <machine/cpu_capabilities.h>
+
+#include "libc_private.h" // for LIBC_ABORT
 
 #ifdef I_AM_PSORT_R
 typedef int		 cmp_t(void *, const void *, const void *);
@@ -94,10 +97,8 @@
     size_t es;
     size_t turnoff;
     dispatch_queue_t queue;
-    pthread_cond_t cond;
-    pthread_mutex_t mutex;
-    OSSpinLock sharedlock;
-    int count;
+    dispatch_group_t group;
+    os_unfair_lock sharedlock;
 };
 
 static union args *
@@ -105,7 +106,7 @@
 {
     union args *args;
 
-    OSSpinLockLock(&shared->sharedlock);
+    os_unfair_lock_lock(&shared->sharedlock);
     if(!shared->freelist) {
 	struct page *page;
 	union args *prev;
@@ -123,17 +124,17 @@
     }
     args = shared->freelist;
     shared->freelist = args->next;
-    OSSpinLockUnlock(&shared->sharedlock);
+    os_unfair_lock_unlock(&shared->sharedlock);
     return args;
 }
 
 static void
 returnargs(struct shared *shared, union args *args)
 {
-    OSSpinLockLock(&shared->sharedlock);
+    os_unfair_lock_lock(&shared->sharedlock);
     args->next = shared->freelist;
     shared->freelist = args;
-    OSSpinLockUnlock(&shared->sharedlock);
+    os_unfair_lock_unlock(&shared->sharedlock);
 }
 
 /*
@@ -154,9 +155,7 @@
 	es % sizeof(long) ? 2 : es == sizeof(long)? 0 : 1;
 
 static inline void
-swapfunc(a, b, n, swaptype)
-	char *a, *b;
-	int n, swaptype;
+swapfunc(char *a, char *b, int n, int swaptype)
 {
 	if(swaptype <= 1)
 		swapcode(long, a, b, n)
@@ -321,8 +320,8 @@
 			args->a = a;
 			args->n = r;
 			args->depth_limit = depth_limit;
-			OSAtomicIncrement32(&shared->count);
-			dispatch_async_f(shared->queue, args, _psort_parallel);
+			dispatch_group_async_f(shared->group, shared->queue, args,
+					_psort_parallel);
 		} else {
 #ifdef I_AM_PSORT_R
 			_psort(a, r, es, thunk, cmp, depth_limit, NULL);
@@ -352,11 +351,6 @@
 #endif
 		shared->cmp, args->depth_limit, shared);
 	returnargs(shared, args);
-	if(OSAtomicDecrement32(&shared->count) <= 0) {
-		pthread_mutex_lock(&shared->mutex);
-		pthread_cond_signal(&shared->cond);
-		pthread_mutex_unlock(&shared->mutex);
-	}
 }
 
 /* fast, approximate integer square root */
@@ -381,7 +375,7 @@
 		union args *args;
 
 		bzero(&shared, sizeof(shared));
-		shared.sharedlock = OS_SPINLOCK_INIT;
+		shared.sharedlock = OS_UNFAIR_LOCK_INIT;
 		if ((args = getargs(&shared)) != NULL) {
 			struct page *p, *pp;
 #ifdef I_AM_PSORT_R
@@ -395,8 +389,7 @@
 			shared.cmp = cmp;
 			shared.es = es;
 			shared.queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
-			shared.cond = (pthread_cond_t)PTHREAD_COND_INITIALIZER;
-			shared.mutex = (pthread_mutex_t)PTHREAD_MUTEX_INITIALIZER;
+			shared.group = dispatch_group_create();
 			args->a = a;
 			args->n = n;
 			args->depth_limit = DEPTH(n);
@@ -415,17 +408,11 @@
 			 * this purpose.
 			 */
 			shared.turnoff = isqrt(n);
-			OSAtomicIncrement32(&shared.count);
 			_psort_parallel(args);
 
 			/* wait for queue to drain */
-			pthread_mutex_lock(&shared.mutex);
-			while(shared.count > 0)
-				pthread_cond_wait(&shared.cond, &shared.mutex);
-
-			pthread_mutex_unlock(&shared.mutex);
-			pthread_mutex_destroy(&shared.mutex);
-			pthread_cond_destroy(&shared.cond);
+			dispatch_group_wait(shared.group, DISPATCH_TIME_FOREVER);
+			dispatch_release(shared.group);
 			for(p = shared.pagelist; p; p = pp) {
 				pp = p->next;
 				munmap(p, PAGESIZE);