Fix definition of CC

.travis.yml

@@ -42,15 +42,15 @@ matrix:
         - PYTHON_VERSION=3.5
         - CONDA_DEPENDENCIES="setuptools sphinx cython numpy pytest-cov clang llvm-openmp"
         - OPENMP_EXPECTED=True
-        - CC=clang
+        - CCOMPILER=clang
 
     # Test gcc on OSX
     - os: osx
       env:
         - PYTHON_VERSION=3.5
         - CONDA_DEPENDENCIES="setuptools sphinx cython numpy pytest-cov gcc"
         - OPENMP_EXPECTED=True
-        - CC=gcc
+        - CCOMPILER=gcc
 
   # Uncomment the following if there are issues in setuptools that we
   # can't work around quickly - otherwise leave uncommented so that
@@ -76,6 +76,15 @@ before_install:
         fi
       fi
 
+    # We need to use CCOMPILER otherwise Travis overwrites CC if we define it
+    # in env: above.
+    - if [ ! -z $CCOMPILER ]; then
+        export CC=$CCOMPILER;
+      fi
+
+    # Check CC variable
+    - echo $CC
+
 install:
 
     - git clone git://github.com/astropy/ci-helpers.git