diff --git a/.travis.yml b/.travis.yml
index 26517d5c..76eeafba 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -49,7 +49,8 @@ matrix:
       env:
         - LLVM_VERSION=3.8.0
         - LLVM_ARCHIVE_PATH=$HOME/clang+llvm.tar.xz
-        - COMPILER="$HOME/clang-$LLVM_VERSION/bin/clang++ -I$HOME/clang-$LLVM_VERSION/include"
+        - COMPILER=$HOME/clang-$LLVM_VERSION/bin/clang++
+        - CPPFLAGS="-I $HOME/clang-$LLVM_VERSION/include"
       before_install:
        - wget http://llvm.org/releases/$LLVM_VERSION/clang+llvm-$LLVM_VERSION-x86_64-linux-gnu-ubuntu-14.04.tar.xz -O $LLVM_ARCHIVE_PATH
        - mkdir $HOME/clang-$LLVM_VERSION