From: Willy Tarreau <w@1wt.eu>
Date: Wed, 31 Aug 2022 08:52:25 +0000 (+0200)
Subject: BUILD: debug: make sure debug macros are never empty
X-Git-Tag: v2.7-dev5~32
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d8009a1ca6607bfe08978476ae2c77679b2b5453;p=thirdparty%2Fhaproxy.git

BUILD: debug: make sure debug macros are never empty

As outlined in commit f7ebe584d7 ("BUILD: debug: Add braces to if
statement calling only CHECK_IF()"), the BUG_ON() family of macros
is incorrectly defined to be empty when debugging is disabled, and
that can lead to trouble. Make sure they always fall back to the
usual "do { } while (0)". This may be backported to 2.6 if needed,
though no such issue was met there to date.
---

diff --git a/include/haproxy/bug.h b/include/haproxy/bug.h
index d65c1567c3..60b2467936 100644
--- a/include/haproxy/bug.h
+++ b/include/haproxy/bug.h
@@ -140,9 +140,9 @@ static inline __attribute((always_inline)) void ha_crash_now(void)
 #  define CHECK_IF(cond)     _BUG_ON_ONCE(cond, __FILE__, __LINE__, 1, "FATAL: check ",   "")
 # endif
 #else
-#  define BUG_ON(cond)
-#  define WARN_ON(cond)
-#  define CHECK_IF(cond)
+#  define BUG_ON(cond)       do { } while (0)
+#  define WARN_ON(cond)      do { } while (0)
+#  define CHECK_IF(cond)     do { } while (0)
 #endif
 
 /* These macros are only for hot paths and remain disabled unless DEBUG_STRICT is 2 or above.
@@ -164,8 +164,8 @@ static inline __attribute((always_inline)) void ha_crash_now(void)
 #  define CHECK_IF_HOT(cond) _BUG_ON_ONCE(cond, __FILE__, __LINE__, 1, "FATAL: check ",   "")
 # endif
 #else
-#  define BUG_ON_HOT(cond)
-#  define CHECK_IF_HOT(cond)
+#  define BUG_ON_HOT(cond)   do { } while (0)
+#  define CHECK_IF_HOT(cond) do { } while (0)
 #endif