From 3f004042927aedaa3596e7b5b186682ea4e405fc Mon Sep 17 00:00:00 2001
From: Simon McVittie <simon.mcvittie@collabora.co.uk>
Date: Tue, 1 Feb 2011 19:09:31 +0000
Subject: [PATCH 1/2] Allow PIE to be disabled, to work around broken toolchains

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=16621
---
 configure.in |   34 +++++++++++++++++++++-------------
 1 files changed, 21 insertions(+), 13 deletions(-)

diff --git a/configure.in b/configure.in
index 08bd962..17d2a06 100644
--- a/configure.in
+++ b/configure.in
@@ -1208,19 +1208,6 @@ if test "x$GCC" = "xyes"; then
      ;;
   esac
 
-  case " $CFLAGS " in
-  *[\ \	]-fPIE[\ \	]*) ;;
-  *) if test x$dbus_win = xno && cc_supports_flag -fPIE; then
-        PIE_CFLAGS="-fPIE"
-        if ld_supports_flag -z,relro; then
-           PIE_LDFLAGS="-pie -Wl,-z,relro"
-        else
-           PIE_LDFLAGS="-pie"
-        fi
-     fi
-     ;;
-  esac
-
   ### Disabled warnings, and compiler flag overrides
 
   # Let's just ignore unused for now
@@ -1296,6 +1283,27 @@ fi
 
 AC_SUBST(PIC_CFLAGS)
 AC_SUBST(PIC_LDFLAGS)
+
+# Disabling position-independent executables means we can't take advantage
+# of address space layout randomization, but some toolchains have known-broken
+# support for PIE. See https://bugs.freedesktop.org/show_bug.cgi?id=16621
+AC_ARG_ENABLE([pie],
+  [AS_HELP_STRING([--disable-pie],
+    [disable PIE to work around broken toolchains: this breaks ASLR, which is a security feature])],
+  [enable_pie=$enableval],
+  [enable_pie=yes])
+PIE_CFLAGS=
+PIE_LDFLAGS=
+if test "x$GCC,$enable_pie,$dbus_win" = xyes,yes,no; then
+  if cc_supports_flag -fPIE; then
+    PIE_CFLAGS="-fPIE"
+    if ld_supports_flag -z,relro; then
+      PIE_LDFLAGS="-pie -Wl,-z,relro"
+    else
+      PIE_LDFLAGS="-pie"
+    fi
+  fi
+fi
 AC_SUBST(PIE_CFLAGS)
 AC_SUBST(PIE_LDFLAGS)
 
-- 
1.7.2.3