diff --git a/.travis.yml b/.travis.yml
index 02cedf9..ac0ce7c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -97,6 +97,7 @@ matrix:
         apt:
           packages:
             - clang-3.5
+            - libstdc++-4.9-dev
           sources:
             - ubuntu-toolchain-r-test
             - llvm-toolchain-precise-3.5
@@ -130,6 +131,7 @@ matrix:
         apt:
           packages:
             - clang-3.8
+            - libstdc++-4.9-dev
           sources:
             - ubuntu-toolchain-r-test
             - llvm-toolchain-precise-3.8
@@ -141,6 +143,7 @@ matrix:
         apt:
           packages:
             - clang-3.9
+            - libstdc++-4.9-dev
           sources:
             - ubuntu-toolchain-r-test
             - llvm-toolchain-precise-3.9