From: Willy Tarreau <w@1wt.eu>
Date: Thu, 18 Oct 2018 14:12:28 +0000 (+0200)
Subject: BUILD: memory: fix pointer declaration for atomic CAS
X-Git-Tag: v1.9-dev4~17
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ac6c880;p=thirdparty%2Fhaproxy.git

BUILD: memory: fix pointer declaration for atomic CAS

The calls to HA_ATOMIC_CAS() on the lockfree version of the pool allocator
were mistakenly done on (void*) for the old value instead of (void **).
While this has no impact on "recent" gcc, it does have one for gcc < 4.7
since the CAS was open coded and it's not possible to assign a temporary
variable of type "void".

No backport is needed, this only affects 1.9.
---

diff --git a/include/common/memory.h b/include/common/memory.h
index a0b6d62031..da96b82926 100644
--- a/include/common/memory.h
+++ b/include/common/memory.h
@@ -272,7 +272,7 @@ static inline void __pool_free(struct pool_head *pool, void *ptr)
 	do {
 		*POOL_LINK(pool, ptr) = (void *)free_list;
 		__ha_barrier_store();
-	} while (!HA_ATOMIC_CAS(&pool->free_list, (void *)&free_list, ptr));
+	} while (!HA_ATOMIC_CAS(&pool->free_list, (void **)&free_list, ptr));
 	HA_ATOMIC_SUB(&pool->used, 1);
 }
 
diff --git a/src/memory.c b/src/memory.c
index 51c623a851..d75dc7e6e0 100644
--- a/src/memory.c
+++ b/src/memory.c
@@ -168,7 +168,7 @@ void *__pool_refill_alloc(struct pool_head *pool, unsigned int avail)
 		do {
 			*POOL_LINK(pool, ptr) = free_list;
 			__ha_barrier_store();
-		} while (HA_ATOMIC_CAS(&pool->free_list, (void *)&free_list, ptr) == 0);
+		} while (HA_ATOMIC_CAS(&pool->free_list, (void **)&free_list, ptr) == 0);
 	}
 
 	HA_ATOMIC_ADD(&pool->allocated, allocated - allocated_orig);
@@ -199,7 +199,7 @@ void pool_flush(struct pool_head *pool)
 		return;
 	do {
 		next = pool->free_list;
-	} while (!HA_ATOMIC_CAS(&pool->free_list, (void *)&next, NULL));
+	} while (!HA_ATOMIC_CAS(&pool->free_list, (void **)&next, NULL));
 	while (next) {
 		temp = next;
 		next = *POOL_LINK(pool, temp);