From c7b252aa09773364781a03bbf498782573ee8585 Mon Sep 17 00:00:00 2001
From: Albert Ou <aou@eecs.berkeley.edu>
Date: Fri, 27 Sep 2019 22:18:56 +0000
Subject: [PATCH] toolchains: Check for GNU make 4.x

GNU make 4.x is needed to cross-compile glibc 2.28 and newer.
This ensures the problem is caught earlier on CentOS release 7.6, whose
default make version remains 3.82.
---
 scripts/build-toolchains.sh | 7 +++++++
 scripts/build-util.sh       | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/scripts/build-toolchains.sh b/scripts/build-toolchains.sh
index 734398c3..738b5ae7 100755
--- a/scripts/build-toolchains.sh
+++ b/scripts/build-toolchains.sh
@@ -99,6 +99,13 @@ if [ "${EC2FASTINSTALL}" = true ] ; then
     git submodule deinit "${module}" || :
 
 else
+    "${MAKE}" --version | (
+        read -r makever
+        case ${makever} in
+        'GNU Make '[4-9]\.*|'GNU Make '[1-9][0-9]) ;;
+        *) false ;;
+        esac; ) || die 'obsolete make version; need GNU make 4.x or later'
+
     module_prepare riscv-gnu-toolchain qemu
     module_build riscv-gnu-toolchain --prefix="${RISCV}"
     echo '==>  Building GNU/Linux toolchain'
diff --git a/scripts/build-util.sh b/scripts/build-util.sh
index 5ca38147..be58a6a1 100644
--- a/scripts/build-util.sh
+++ b/scripts/build-util.sh
@@ -14,7 +14,7 @@ case ${ncpu} in
 *) export MAKEFLAGS="-j ${ncpu} ${MAKEFLAGS}" ;;
 esac
 
-MAKE=$(command -v gmake || command -v make)
+MAKE=$(command -v gnumake || command -v gmake || command -v make)
 readonly MAKE