travis-ci: run gcc-8 on linux-gcc jobs

pclouds · gitster · commit 37fa4b3c78f4 · 2018-05-21T14:14:09.000+09:00
Switch from gcc-4.8 to gcc-8. Newer compilers come with more warning
checks (usually in -Wextra).  Since -Wextra is enabled in developer
mode (which is also enabled in travis), this lets travis report more
warnings before other people do it.

Signed-off-by: Nguyễn Thái Ngọc Duy &lt;pclouds@gmail.com&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
diff --git a/.travis.yml b/.travis.yml
@@ -16,10 +16,13 @@ compiler:
 
 addons:
   apt:
+    sources:
+    - ubuntu-toolchain-r-test
     packages:
     - language-pack-is
     - git-svn
     - apache2
+    - gcc-8
 
 matrix:
   include:
diff --git a/ci/lib-travisci.sh b/ci/lib-travisci.sh
@@ -99,6 +99,9 @@ export DEFAULT_TEST_TARGET=prove
 export GIT_PROVE_OPTS="--timer --jobs 3 --state=failed,slow,save"
 export GIT_TEST_OPTS="--verbose-log -x"
 export GIT_TEST_CLONE_2GB=YesPlease
+if [ "$jobname" = linux-gcc ]; then
+	export CC=gcc-8
+fi
 
 case "$jobname" in
 linux-clang|linux-gcc)
