configure.ac: Set $CPPFLAGS when checking for no_app_regs.

Fixes compilation for sparc64 with clang.

diff --git a/configure.ac b/configure.ac
index 908bb81e7e5ac5a47b9865969bd0640d849e2177..9e24d896dd705f4bdd5e352b6c86f3813e0f2d92 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -741,6 +741,7 @@ if test x"$target_cpu" = xsparc64 ; then
         break
       fi
       CFLAGS="$TARGET_CFLAGS $cand -Werror"
+      CPPFLAGS="$TARGET_CPPFLAGS"
       AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[]])],
                        [grub_cv_target_cc_mno_app_regs="$cand"], [])
     done