[patch] Ported the Grub2 -fPIE Check

grub-0.97-fpie_check.patch (text/plain), 1.39 KB, created by Magnus Granberg on 2009-09-05 16:16:00 UTC

2009-09-05	Magnus Granberg		<[e-mail]>

		# #139277 #168834 #281246
		* configure.ac: Add grub_CHECK_PIE. It check if the compiler
		include -fPIE in the default specs.
		* configure.ac: Check if pie_possible is yes and add -nopie
		to STAGE1_CFLAGS and STAGE2_CFLAGS.

--- configure.ac.zorry	2009-09-05 15:54:43.000000000 +0200
+++ configure.ac	2009-09-05 16:35:48.000000000 +0200
@@ -110,6 +110,42 @@
   fi
 fi
 
+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 "$ac_compile -S -o conftest.s" 2> /dev/null; then]
+  AC_MSG_RESULT([yes])
+  [# Should we clear up other files as well, having called `AC_LANG_CONFTEST'?
+  rm -f conftest.s
+else
+  pie_possible=no]
+  AC_MSG_RESULT([no])
+[fi]
+])
+
+# Position independent executable.
+grub_CHECK_PIE
+[# Need that, because some distributions ship compilers that include
+# `-fPIE' in the default specs.
+if [ x"$pie_possible" = xyes ]; then
+  STAGE1_CFLAGS="$STAGE1_CFLAGS -nopie"
+  STAGE2_CFLAGS="$STAGE2_CFLAGS -nopie"
+fi]
+
 AC_SUBST(STAGE1_CFLAGS)
 AC_SUBST(STAGE2_CFLAGS)
 AC_SUBST(GRUB_CFLAGS)