travis-ci: build with the right compiler

szeder · gitster · commit 2c8921db2b86 · 2019-01-17T11:14:45.000-08:00
Our 'Makefile' hardcodes the compiler to build Git as 'CC = cc'. This CC variable can be overridden from the command line, i.e. 'make CC=gcc-X.Y' will build with that particular GCC version, but not from the environment, i.e. 'CC=gcc-X.Y make' will still build with whatever 'cc' happens to be on the platform. Our build jobs on Travis CI are badly affected by this. In the build matrix we have dedicated build jobs to build Git with GCC and Clang both on Linux and macOS from the very beginning (522354d (Add Travis CI support, 2015-11-27)). Alas, this never really worked as supposed to, because Travis CI specifies the compiler for those build jobs as 'export CC=gcc' and 'export CC=clang' (which works fine for projects built with './configure && make'). Consequently, our 'linux-clang' build job has always used GCC, because that's where 'cc' points at in Travis CI's Linux images, while the 'osx-gcc' build job has always used Clang. Furthermore, 37fa4b3 (travis-ci: run gcc-8 on linux-gcc jobs, 2018-05-19) added an 'export CC=gcc-8' in an attempt to build with a more modern compiler, but to no avail. Set MAKEFLAGS with CC based on the $CC environment variable, so 'make' will run the "right" compiler. The Xcode 10.1 macOS image on Travis CI already contains the gcc@8 package from Homebrew, but we have to 'brew link' it first to be able to use it. So with this patch our build jobs will build Git with the following compiler versions: linux-clang: clang version 5.0.0 (tags/RELEASE_500/final) linux-gcc: gcc-8 (Ubuntu 8.1.0-5ubuntu1~14.04) 8.1.0 osx-clang: Apple LLVM version 10.0.0 (clang-1000.11.45.5) osx-gcc: gcc-8 (Homebrew GCC 8.2.0) 8.2.0 GETTEXT_POISON: gcc (Ubuntu 4.8.4-2ubuntu1~14.04.3) 4.8.4 Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/ci/install-dependencies.sh b/ci/install-dependencies.sh
@@ -40,6 +40,11 @@ osx-clang|osx-gcc)
 	brew install git-lfs gettext
 	brew link --force gettext
 	brew install caskroom/cask/perforce
+	case "$jobname" in
+	osx-gcc)
+		brew link gcc@8
+		;;
+	esac
 	;;
 StaticAnalysis)
 	sudo apt-get -q update
diff --git a/ci/lib-travisci.sh b/ci/lib-travisci.sh
@@ -99,12 +99,14 @@ export DEFAULT_TEST_TARGET=prove
 export GIT_PROVE_OPTS="--timer --jobs 3 --state=failed,slow,save"
 export GIT_TEST_OPTS="--verbose-log -x --immediate"
 export GIT_TEST_CLONE_2GB=YesPlease
-if [ "$jobname" = linux-gcc ]; then
-	export CC=gcc-8
-fi
 
 case "$jobname" in
 linux-clang|linux-gcc)
+	if [ "$jobname" = linux-gcc ]
+	then
+		export CC=gcc-8
+	fi
+
 	export GIT_TEST_HTTPD=YesPlease
 
 	# The Linux build installs the defined dependency versions below.
@@ -118,6 +120,11 @@ linux-clang|linux-gcc)
 	export PATH="$GIT_LFS_PATH:$P4_PATH:$PATH"
 	;;
 osx-clang|osx-gcc)
+	if [ "$jobname" = osx-gcc ]
+	then
+		export CC=gcc-8
+	fi
+
 	# t9810 occasionally fails on Travis CI OS X
 	# t9816 occasionally fails with "TAP out of sequence errors" on
 	# Travis CI OS X
@@ -127,3 +134,5 @@ GIT_TEST_GETTEXT_POISON)
 	export GIT_TEST_GETTEXT_POISON=YesPlease
 	;;
 esac
+
+export MAKEFLAGS="CC=${CC:-cc}"
