[coreboot-gerrit] New patch to review for coreboot: buildgcc: Never set GMP CFLAGS manually in order to get the right flags

[Paul Kocialkowski (contact@paulk.fr)]

Paul Kocialkowski (contact at paulk.fr) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/15452

-gerrit

commit baadd6aa8e89f4c17189309bf3b54640a2c12de0
Author: Paul Kocialkowski <contact at paulk.fr>
Date:   Fri Jun 17 21:41:00 2016 -0700

    buildgcc: Never set GMP CFLAGS manually in order to get the right flags
    
    When no CFLAGS are explicitly provided to it, the GMP configure script
    will figure out the best optimization flags to use on its own. In
    particular, it will setup the march, mfpu and mtune flags based on
    hardware detection.
    
    However, when CFLAGS are provided, they are used as-is and such
    detection doesn't happen. When the march, mfpu and mtune flags are not
    provided (which happens when GMP wasn't built already), not only will
    related optimizations be disabled, but some code might not build because
    of missing support. This happens with NEON instructions on ARMv7 hosts.
    
    Thus, it is better not to set CFLAGS and leave it up to the GMP
    configure script to get them right and still reuse those later.
    
    Change-Id: I6ffcbac1298523d1b8ddf29a8bca1b00298828a7
    Signed-off-by: Paul Kocialkowski <contact at paulk.fr>
---
 util/crossgcc/buildgcc | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/util/crossgcc/buildgcc b/util/crossgcc/buildgcc
index 1e761da..118a50b 100755
--- a/util/crossgcc/buildgcc
+++ b/util/crossgcc/buildgcc
@@ -404,10 +404,6 @@ GNU General Public License for more details.
 EOF
 }
 
-have_hostcflags_from_gmp() {
-	grep -q __GMP_CFLAGS $DESTDIR$TARGETDIR/include/gmp.h >/dev/null 2>&1
-}
-
 set_hostcflags_from_gmp() {
 	# Now set CFLAGS to match GMP CFLAGS but strip out -pedantic
 	# as GCC 4.6.x fails if it's there.
@@ -416,7 +412,7 @@ set_hostcflags_from_gmp() {
 }
 
 build_GMP() {
-	CC="$CC" CFLAGS="$HOSTCFLAGS" \
+	CC="$CC" \
 		../${GMP_DIR}/configure --disable-shared --enable-fat \
 		--prefix=$TARGETDIR $OPTIONS \
 		|| touch .failed
@@ -788,11 +784,6 @@ elif [ $UNAME = "NetBSD" ]; then
 fi
 fi # GCC
 
-export HOSTCFLAGS="-Os"
-if have_hostcflags_from_gmp; then
-	set_hostcflags_from_gmp
-fi
-
 if [ "$USECCACHE" = 1 ]; then
 	CC="ccache $CC"
 fi