Merge pull request #46 from Forceflow/fixtravix

Travis: Use GCC9 to build on bionic for icelake compilation support

Author: Forceflow

Diff for: .travis.yml

@@ -1,13 +1,16 @@
 dist: bionic
 language: cpp
 compiler: gcc
-before_install:
-  - sudo apt-get update
-  - sudo apt-get -y install gcc-8
+addons:
+  apt:
+    sources:
+      - ubuntu-toolchain-r-test
+    packages:
+      - gcc-9 g++-9
 script: 
   - cd test
-  - make CXX=g++-8 bmi2
-  - make CXX=g++-8 avx512
-  - make CXX=g++-8 test
+  - make CXX=g++-9 bmi2
+  - make CXX=g++-9 avx512
+  - make CXX=g++-9 test
 # This really should finish in less than 2 minutes - otherwise something's wrong
   - timeout 120 ./libmorton_test 128