From: Nick Mathewson <nickm@torproject.org>
Date: Sat, 31 Jan 2009 07:31:47 +0000 (+0000)
Subject: Build with the -fno-strict-aliasing flag on GCC.
X-Git-Tag: release-2.0.1-alpha~106
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=52eb4951302554dd696d6a0120ad5d3f6cffb7bb;p=libevent

Build with the -fno-strict-aliasing flag on GCC.

You do not want to know about the 2 hours I just spent tracking down
an evdns bug that only affected me on some platforms to the way we
were using sockaddr* and sockaddr_in*.  Suffice it to say that I do
not think this is the only C99-aliasing-dubiousness in our code, nor
that I am smart enough to keep my code correct with the GCC's strict
aliasing optimizations in place.

svn:r1079
---

diff --git a/configure.in b/configure.in
index 503e4b49..6b084582 100644
--- a/configure.in
+++ b/configure.in
@@ -19,7 +19,11 @@ AC_PROG_LN_S
 
 AC_PROG_GCC_TRADITIONAL
 if test "$GCC" = yes ; then
+        # Enable many gcc warnings by default...
         CFLAGS="$CFLAGS -Wall"
+	# And disable the strict-aliasing optimization, since it breaks
+	# our sockaddr-handling code in strange ways.
+	CFLAGS="$CFLAGS -fno-strict-aliasing"
 fi
 
 AC_ARG_ENABLE(gcc-warnings,
@@ -433,13 +437,13 @@ if test x$enable_gcc_warnings = xyes; then
   CFLAGS="$CFLAGS -W -Wfloat-equal -Wundef -Wpointer-arith -Wstrict-prototypes -Wmissing-prototypes -Wwrite-strings -Wredundant-decls -Wchar-subscripts -Wcomment -Wformat -Wwrite-strings -Wmissing-declarations -Wredundant-decls -Wnested-externs -Wbad-function-cast -Wswitch-enum -Werror"
   CFLAGS="$CFLAGS -Wno-unused-parameter -Wno-sign-compare -Wstrict-aliasing"
 
-  if test x$have_gcc4 = xyes ; then 
+  if test x$have_gcc4 = xyes ; then
     # These warnings break gcc 3.3.5 and work on gcc 4.0.2
     CFLAGS="$CFLAGS -Winit-self -Wmissing-field-initializers -Wdeclaration-after-statement"
     #CFLAGS="$CFLAGS -Wold-style-definition"
   fi
 
-  if test x$have_gcc42 = xyes ; then 
+  if test x$have_gcc42 = xyes ; then
     # These warnings break gcc 4.0.2 and work on gcc 4.2
     CFLAGS="$CFLAGS -Waddress -Wnormalized=id -Woverride-init"
   fi
diff --git a/evdns.c b/evdns.c
index d86d52a0..aad21e27 100644
--- a/evdns.c
+++ b/evdns.c
@@ -3468,6 +3468,7 @@ main(int c, char **v) {
 		++idx;
 	}
 	event_init();
+	evdns_init();
 	if (verbose)
 		evdns_set_log_fn(logfn);
 	evdns_resolv_conf_parse(DNS_OPTION_NAMESERVERS, "/etc/resolv.conf");