From 3bae3b8527b938db6413e0d9062c74fe0c0278e7 Mon Sep 17 00:00:00 2001
From: Colin Watson <cjwatson@debian.org>
Date: Fri, 22 Jan 2016 10:58:53 +0000
Subject: Work around unsupported relocations on arm64

The patch for https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63304 causes
the toolchain to emit relocations that GRUB does not support.
-mpc-relative-literal-loads works around this.
---
 configure.ac | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/configure.ac b/configure.ac
index 24b9cbf..010175d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -936,6 +936,21 @@ if test "x$grub_cv_target_cc_qn" = xyes; then
   TARGET_CFLAGS="$TARGET_CFLAGS -Qn"
 fi
 
+if test "x$target_cpu" = xarm64; then
+  # Work around unsupported relocations as reported in
+  # https://lists.gnu.org/archive/html/grub-devel/2015-12/msg00092.html; see
+  # also: https://bugs.launchpad.net/bugs/1533009
+  AC_CACHE_CHECK([whether option -mpc-relative-literal-loads], grub_cv_cc_mpc_relative_literal_loads, [
+    CFLAGS="$TARGET_CFLAGS -mpc-relative-literal-loads -Werror"
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[]])],
+		      [grub_cv_cc_mpc_relative_literal_loads=yes],
+		      [grub_cv_cc_mpc_relative_literal_loads=no])
+  ])
+  if test "x$grub_cv_cc_mpc_relative_literal_loads" = xyes; then
+    TARGET_CFLAGS="$TARGET_CFLAGS -mpc-relative-literal-loads"
+  fi
+fi
+
 #
 # Compiler features.
 #