[travis] fix apt package installs

.travis.yml

@@ -29,11 +29,11 @@ matrix:
       addons:
         apt:
           sources: [ 'ubuntu-toolchain-r-test']
-        packages: [ 'libstdc++6']
+          packages: [ 'libstdc++6', 'libstdc++-5-dev']
     - os: linux
       sudo: false
       compiler: ": clang-coverage"
-      env: JOBS=8 COVERAGE=true LLVM_VERSION="3.8" _CXX="ccache clang++-3.8 -Qunused-arguments" _CC="clang-3.8"
+      env: JOBS=8 COVERAGE=true _CXX="ccache clang++-3.8 -Qunused-arguments" _CC="clang-3.8"
       addons:
         apt:
           sources: [ 'ubuntu-toolchain-r-test']
@@ -86,7 +86,7 @@ script:
  - cat config.log
  - make
  - make test
- - enabled ${COVERAGE} coverage
+ - enabled ${COVERAGE} export LLVM_COV="$(mason prefix clang 3.8.0)/bin/llvm-cov" && coverage
  - enabled ${BENCH} make bench
 
 after_success:

scripts/travis-common.sh

@@ -92,7 +92,7 @@ configure () {
 
 coverage () {
     ./mason_packages/.link/bin/cpp-coveralls \
-        --gcov /usr/bin/llvm-cov-${LLVM_VERSION} \
+        --gcov ${LLVM_COV} \
         --build-root . --gcov-options '\-lp' \
         --exclude mason_packages \
         --exclude .sconf_temp --exclude benchmark --exclude deps \