diff --git a/.travis.yml b/.travis.yml
index 8129bb8..82404d5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -89,14 +89,14 @@ matrix:
             - <<: *xenial-clang
               sourceline: 'deb https://apt.llvm.org/xenial/ llvm-toolchain-xenial-5.0 main'
             - ubuntu-toolchain-r-test
-          packages: [clang++-5.0, libc++-]
+          packages: [clang++-5.0, libc++-dev]
       env: COMPILER=clang++-5.0 CXXSTD=11
     - &clang-6
       compiler: clang
       addons:
         apt:
           sources: [llvm-toolchain-xenial-6.0, ubuntu-toolchain-r-test]
-          packages: [clang++-6.0, libc++-]
+          packages: [clang++-6.0, libc++-dev]
       env: COMPILER=clang++-6.0 CXXSTD=11
     - &clang-7
       compiler: clang