From f93ddcfd1cacc2b0c892408d85f491fd54cc84c1 Mon Sep 17 00:00:00 2001
From: Vladimir Serbinenko <phcoder@gmail.com>
Date: Sat, 23 Nov 2013 12:40:44 +0100
Subject: [PATCH] 	Don't add -mflush-func if it's not supported by
 compiler.

---
 ChangeLog            |  4 ++++
 conf/Makefile.common |  3 ---
 configure.ac         | 15 +++++++++++++++
 3 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 0c87f158c..fb67de1d3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2013-11-23  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	Don't add -mflush-func if it's not supported by compiler.
+
 2013-11-23  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	Move common BIOS/coreboot memory map declarations to
diff --git a/conf/Makefile.common b/conf/Makefile.common
index 835aeeac5..9f0d1d6d5 100644
--- a/conf/Makefile.common
+++ b/conf/Makefile.common
@@ -10,9 +10,6 @@ if COND_mips_loongson
   CFLAGS_PLATFORM += -mexplicit-relocs
   CPPFLAGS_PLATFORM = -DUSE_ASCII_FALLBACK
 endif
-if COND_mips
-  CFLAGS_PLATFORM += -mflush-func=grub_red_herring
-endif
 if COND_sparc64_ieee1275
   CFLAGS_PLATFORM += -mno-app-regs
   LDFLAGS_PLATFORM = -Wl,-melf64_sparc -mno-relax
diff --git a/configure.ac b/configure.ac
index cb12f2401..8619a676e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -520,6 +520,21 @@ if test "x$grub_cv_cc_target_clang" = xno && test "x$target_cpu" = xi386 && test
    TARGET_CFLAGS="$TARGET_CFLAGS -mrtd -mregparm=3"
 fi
 
+# on mips redirect cache flushing function to non-existant one.
+if test "x$target_cpu" = xmips || test "x$target_cpu" = xmipsel ; then
+  AC_CACHE_CHECK([whether -mflush-func=grub_red_herring works], [grub_cv_cc_mflush_func], [
+    CFLAGS="$TARGET_CFLAGS -mflush-func=grub_red_herring -Werror"
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[]])],
+        [grub_cv_cc_mflush_func=yes],
+	[grub_cv_cc_mflush_func=no])
+  ])
+
+  if test "x$grub_cv_cc_mflush_func" = xyes; then
+    TARGET_CFLAGS="$TARGET_CFLAGS -mflush-func=grub_red_herring"
+  fi
+fi
+
+
 # Force no alignment to save space on i386.
 if test "x$target_cpu" = xi386; then
   AC_CACHE_CHECK([whether -falign-loops works], [grub_cv_cc_falign_loop], [