From: Ben Kallus <benjamin.p.kallus.gr@dartmouth.edu>
Date: Sun, 20 Jul 2025 16:48:07 +0000 (-0400)
Subject: CLEANUP: compiler: prefer char * over void * for pointer arithmetic
X-Git-Tag: v3.3-dev4~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d3b46cca7b208b98fcd090043f8b4af4dd204de1;p=thirdparty%2Fhaproxy.git

CLEANUP: compiler: prefer char * over void * for pointer arithmetic

This patch changes two instances of pointer arithmetic on void *
to use char * instead, to avoid UB. This is essentially to please
UB analyzers, though.
---

diff --git a/include/haproxy/compiler.h b/include/haproxy/compiler.h
index 80d9be772..01a1a62e7 100644
--- a/include/haproxy/compiler.h
+++ b/include/haproxy/compiler.h
@@ -350,7 +350,7 @@
  * <type> which has its member <name> stored at address <ptr>.
  */
 #ifndef container_of
-#define container_of(ptr, type, name) ((type *)(((void *)(ptr)) - ((long)&((type *)0)->name)))
+#define container_of(ptr, type, name) ((type *)(((char *)(ptr)) - ((long)&((type *)0)->name)))
 #endif
 
 /* returns a pointer to the structure of type <type> which has its member <name>
@@ -359,7 +359,7 @@
 #ifndef container_of_safe
 #define container_of_safe(ptr, type, name) \
 	({ void *__p = (ptr); \
-		__p ? (type *)(__p - ((long)&((type *)0)->name)) : (type *)0; \
+		__p ? (type *)((char *)__p - ((long)&((type *)0)->name)) : (type *)0; \
 	})
 #endif