[PATCH] Some distributions ship compilers that include -fPIE in the default specs (Gentoo Hardened)

[Magnus Granberg]

Hi

On Gentoo Hardened we compile with -fPIE in the default specs and
grub fails to compile.
This patch check if the compiler use -fPIE in the default specs and add
-fno-PIE to TARGET_CFLAGS.

--- aclocal.m4.zorry    2008-02-03 14:11:28.000000000 +0100
+++ aclocal.m4  2009-08-22 01:05:56.000000000 +0200
@@ -362,3 +362,31 @@
   AC_MSG_RESULT([no])
 [fi]
 ])
+
+dnl Check if the C compiler supports `-fPIE'.
+AC_DEFUN(grub_CHECK_PIE,[
+[# Position independent executable.
+pie_possible=yes]
+AC_MSG_CHECKING([whether `$CC' has `-fPIE' as default])
+# Is this a reliable test case?
+AC_LANG_CONFTEST([[
+#ifdef __PIE__
+int main() {
+       return 0;
+}
+#else
+#error NO __PIE__ DEFINED
+#endif
+]])
+
+[# `$CC -c -o ...' might not be portable.  But, oh, well...  Is calling
+# `ac_compile' like this correct, after all?
+if eval "$ac_compile -S -o conftest.s" 2> /dev/null; then]
+  AC_MSG_RESULT([yes])
+  [# Should we clear up other files as well, having called `AC_LANG_CONFTEST'?
+  rm -f conftest.s
+else
+  pie_possible=no]
+  AC_MSG_RESULT([no])
+[fi]
+])
--- configure.ac.zorry  2008-02-03 14:41:51.000000000 +0100
+++ configure.ac        2009-09-01 01:05:34.000000000 +0200
@@ -251,6 +251,14 @@
 # Compiler features.
 #
 
+# Position independent executable.
+grub_CHECK_PIE
+[# Need that, because some distributions ship compilers that include
+# `-fPIE' in the default specs.
+if [ x"$pie_possible" = xyes ]; then
+  TARGET_CFLAGS="$TARGET_CFLAGS -fno-PIE"
+fi]
+
 # Smashing stack protector.
 grub_CHECK_STACK_PROTECTOR
 [# Need that, because some distributions ship compilers that include

---
Hardened-Development Overlay
Magnus Granberg (Zorry) <address@hidden>