diff --git a/.travis.yml b/.travis.yml
index 6cea141..ecf9911 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -165,6 +165,7 @@ matrix:
         apt:
           packages:
             - clang-3.6
+            - libstdc++-4.9-dev
           sources:
             - ubuntu-toolchain-r-test