message: travis: try to extend to newer GCC, and clang
diff: @@ -7,6 +7,17 @@ matrix:
  dist: trusty
  sudo: false
  env: BUILD_TARGET=trusty_build
  + compiler: gcc
  + - os: linux
  + dist: trusty
  + sudo: false
  + env: BUILD_TARGET=trusty_build
  + compiler: gcc-5
  + - os: linux
  + dist: trusty
  + sudo: false
  + env: BUILD_TARGET=trusty_build
  + compiler: clang
  - os: linux
  sudo: required
  services:
  