From: Remi Gacogne <remi.gacogne@powerdns.com>
Date: Thu, 5 Jan 2023 14:52:10 +0000 (+0100)
Subject: Enable FORTIFY_SOURCE=3 when supported by the compiler
X-Git-Tag: dnsdist-1.8.0-rc1~110^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1b69ef907a56a23fdeee9ab66931dbde45b54cb3;p=thirdparty%2Fpdns.git

Enable FORTIFY_SOURCE=3 when supported by the compiler

Barely tested, we should at least measure the performance impact and
ponder making that optional.
---

diff --git a/m4/pdns_d_fortify_source.m4 b/m4/pdns_d_fortify_source.m4
index 68e9be5ef5..4a3322519f 100644
--- a/m4/pdns_d_fortify_source.m4
+++ b/m4/pdns_d_fortify_source.m4
@@ -21,8 +21,14 @@ dnl
 AC_DEFUN([AC_CC_D_FORTIFY_SOURCE],[
       OLD_CXXFLAGS="$CXXFLAGS"
       CXXFLAGS="-Wall -W -Werror $CXXFLAGS"
-      gl_COMPILER_OPTION_IF([-D_FORTIFY_SOURCE=2], [
-        CFLAGS="-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 $CFLAGS"
-        CXXFLAGS="-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 $OLD_CXXFLAGS"
-      ], [CXXFLAGS="$OLD_CXXFLAGS"], [AC_LANG_PROGRAM([[#include <stdio.h>]],[])])
-]) 
+      gl_COMPILER_OPTION_IF([-D_FORTIFY_SOURCE=3], [
+        CFLAGS="-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=3 $CFLAGS"
+        CXXFLAGS="-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=3 $OLD_CXXFLAGS"
+      ], [
+          gl_COMPILER_OPTION_IF([-D_FORTIFY_SOURCE=2], [
+            CFLAGS="-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 $CFLAGS"
+            CXXFLAGS="-U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 $OLD_CXXFLAGS"
+          ], [CXXFLAGS="$OLD_CXXFLAGS"], [AC_LANG_PROGRAM([[#include <stdio.h>]],[])])
+         ]
+      , [AC_LANG_PROGRAM([[#include <stdio.h>]],[])])
+])