Update .travis.yml

.travis.yml

@@ -6,6 +6,12 @@
 # http://stackoverflow.com/questions/22111549/travis-ci-with-clang-3-4-and-c11/30925448#30925448
 # to allow C++11, though we are not yet building with -std=c++11
 
+before-install:
+  # Debug information
+  - if [[ "$TRAVIS_OS_NAME" = "linux" ]]; then lsb_release -a; fi
+  - uname -a
+  - $CC --version
+  - $CXX --version
 install:
 # /usr/bin/gcc is 4.6 always, but gcc-X.Y is available.
 - if [ "$CXX" = "g++" ]; then export CXX="g++-4.9" CC="gcc-4.9"; fi