From: Willy Tarreau <w@1wt.eu>
Date: Sat, 20 Oct 2018 15:37:38 +0000 (+0200)
Subject: BUILD: memory: fix free_list pointer declaration again for atomic CAS
X-Git-Tag: v1.9-dev4~13
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=7a6ad88b02d8b74c2488003afb1a7063043ddd2d;p=thirdparty%2Fhaproxy.git

BUILD: memory: fix free_list pointer declaration again for atomic CAS

Commit ac6c880 ("BUILD: memory: fix pointer declaration for atomic CAS")
attemtped to fix a build warning affecting the lock-free version of the
pool allocator. But the fix tried to hide the cause instead of addressing
it, thus clang still complains about (void **) not matching (void ***).

The real solution is to declare free_list (void **) and not to use a cast.
Now this builds fine with gcc/clang with and without threads.

No backport is needed.
---

diff --git a/include/common/memory.h b/include/common/memory.h
index da96b82926..5fde4bcddc 100644
--- a/include/common/memory.h
+++ b/include/common/memory.h
@@ -267,12 +267,12 @@ static inline void *pool_alloc(struct pool_head *pool)
  */
 static inline void __pool_free(struct pool_head *pool, void *ptr)
 {
-	void *free_list = pool->free_list;
+	void **free_list = pool->free_list;
 
 	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, &free_list, ptr));
 	HA_ATOMIC_SUB(&pool->used, 1);
 }