diff --git a/.travis.yml b/.travis.yml
index 3173efc..566b011 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,17 +2,18 @@ language: cpp
 
 env:
   matrix:
-    - CXX=g++-4.9
-    - CXX=g++-4.8
-    - CXX=g++-4.7
+    - COMPILER=g++-4.9
+    - COMPILER=g++-4.8
+    - COMPILER=g++-4.7
 
 before_install:
  - sudo add-apt-repository ppa:ubuntu-toolchain-r/test -y
  - sudo add-apt-repository ppa:boost-latest/ppa -y
  - sudo apt-get update -qq
- - sudo apt-get install -qq cmake libboost1.54-dev libboost-program-options1.54-dev ${CXX}
+ - sudo apt-get install -qq cmake libboost1.54-dev libboost-program-options1.54-dev ${COMPILER}
 
 before_script:
+ - export CXX=${COMPILER}
  - mkdir build
  - cd build
  - cmake -DWITH_UNIT_TESTS=ON ..