From 95b147967216a057d51a1b970da777486be716e3 Mon Sep 17 00:00:00 2001
From: Rich Felker <dalias@aerifal.cx>
Date: Wed, 28 Sep 2011 18:00:02 -0400
Subject: next step making barrier self-sync'd destruction safe

i think this works, but it can be simplified. (next step)
---
 src/thread/pthread_barrier_destroy.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

(limited to 'src/thread/pthread_barrier_destroy.c')

diff --git a/src/thread/pthread_barrier_destroy.c b/src/thread/pthread_barrier_destroy.c
index 3ebc2b39..e0da197a 100644
--- a/src/thread/pthread_barrier_destroy.c
+++ b/src/thread/pthread_barrier_destroy.c
@@ -5,8 +5,12 @@ void __vm_lock(int), __vm_unlock(void);
 int pthread_barrier_destroy(pthread_barrier_t *b)
 {
 	if (b->_b_limit < 0) {
-		int seq = b->_b_seq;
-		if (seq & 1) __wait(&b->_b_seq, 0, seq, 0);
+		if (b->_b_lock) {
+			int v;
+			a_or(&b->_b_lock, INT_MIN);
+			while ((v = b->_b_lock) & INT_MAX)
+				__wait(&b->_b_lock, 0, v, 0);
+		}
 		__vm_lock(-1);
 		__vm_unlock();
 	}
-- 
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