From cc90ec336c77f384dea5fa09af9e36ed21c49f37 Mon Sep 17 00:00:00 2001
From: Lucas Hosseini <hoss@fb.com>
Date: Fri, 20 Sep 2019 19:40:04 +0200
Subject: [PATCH] Fix default args for cpu features.

---
 acinclude/ax_check_cpu.m4 |  9 +++++++--
 configure                 | 10 +++++++---
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/acinclude/ax_check_cpu.m4 b/acinclude/ax_check_cpu.m4
index a0a542cfcd..76465d06e3 100644
--- a/acinclude/ax_check_cpu.m4
+++ b/acinclude/ax_check_cpu.m4
@@ -9,11 +9,16 @@ AC_MSG_CHECKING([for cpu arch])
   case $target in
     amd64-* | x86_64-*)
       ARCH_CPUFLAGS="-mpopcnt -msse4"
-      ARCH_CXXFLAGS="-m64";;
+      ARCH_CXXFLAGS="-m64"
+      ;;
+    aarch64*-*)
+dnl This is an arch for Nvidia Xavier a proper detection would be nice.
+      ARCH_CPUFLAGS="-march=armv8.2-a"
+      ;;
     *) ;;
   esac
 
-AC_MSG_RESULT([$target CPUFLAGS+="$ARCH_CPUFLAGS" CXXFLAGS+="$ARCH_CXXFLAGS"])
+AC_MSG_RESULT([$target CPUFLAGS+=" $ARCH_CPUFLAGS" CXXFLAGS+=" $ARCH_CXXFLAGS"])
 
 AC_SUBST(ARCH_CPUFLAGS)
 AC_SUBST(ARCH_CXXFLAGS)
diff --git a/configure b/configure
index 9f2fe9acc6..9b07329c9d 100755
--- a/configure
+++ b/configure
@@ -6816,12 +6816,16 @@ $as_echo_n "checking for cpu arch... " >&6; }
   case $target in
     amd64-* | x86_64-*)
       ARCH_CPUFLAGS="-mpopcnt -msse4"
-      ARCH_CXXFLAGS="-m64";;
+      ARCH_CXXFLAGS="-m64"
+      ;;
+    aarch64*-*)
+      ARCH_CPUFLAGS="-march=armv8.2-a"
+      ;;
     *) ;;
   esac
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $target CPUFLAGS+=\"$ARCH_CPUFLAGS\" CXXFLAGS+=\"$ARCH_CXXFLAGS\"" >&5
-$as_echo "$target CPUFLAGS+=\"$ARCH_CPUFLAGS\" CXXFLAGS+=\"$ARCH_CXXFLAGS\"" >&6; }
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $target CPUFLAGS+=\" $ARCH_CPUFLAGS\" CXXFLAGS+=\" $ARCH_CXXFLAGS\"" >&5
+$as_echo "$target CPUFLAGS+=\" $ARCH_CPUFLAGS\" CXXFLAGS+=\" $ARCH_CXXFLAGS\"" >&6; }