From: Ralf Habacker <ralf.habacker@freenet.de>
Date: Tue, 8 Mar 2022 08:02:51 +0000 (+0100)
Subject: test-segfault: Fix build error caused by a null pointer dereference warning
X-Git-Tag: dbus-1.15.0~71
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3e8423d2991bc6d7f5b4e54c2513a48c39cd23e8;p=thirdparty%2Fdbus.git

test-segfault: Fix build error caused by a null pointer dereference warning

Only do the deliberate crash via undefined behaviour (which the compiler
is quite right to warn us about!) if raise() isn't available.

The pointer needs to be volatile otherwise the compiler is free to remove
the store.

Part-of: https://gitlab.freedesktop.org/dbus/dbus/-/merge_requests/275
Reviewed-by: Simon McVittie <smcv@collabora.com>
---

diff --git a/test/test-segfault.c b/test/test-segfault.c
index 5c559ccb9..ef905c58d 100644
--- a/test/test-segfault.c
+++ b/test/test-segfault.c
@@ -10,15 +10,16 @@
 int
 main (int argc, char **argv)
 {
-  char *p;  
-
   _dbus_disable_crash_handling ();
 
 #ifdef HAVE_RAISE
   raise (SIGSEGV);
+#else
+  {
+    volatile char *p = NULL;
+    *p = 'a';
+  }
 #endif
-  p = NULL;
-  *p = 'a';
-  
+
   return 0;
 }