diff --git a/.travis.yml b/.travis.yml
index 5de21f3..61b628f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -22,6 +22,7 @@ matrix:
         - rustup target add $TARGET
       script:
         - cargo build --verbose --target $TARGET --no-default-features --features i128
+        - cargo build --verbose --target $TARGET --no-default-features --features libm
     - name: "rustfmt"
       rust: 1.31.0
       before_script: