diff --git a/.travis.yml b/.travis.yml
index 2b6b22b..98c7776 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -41,6 +41,7 @@ before_install:
 install:
   - source ~/.cargo/env || true
   - |
+    echo "TRAVIS_RUST_VERSION:$TRAVIS_RUST_VERSION"
     if [ "$TRAVIS_RUST_VERSION" == "nightly" ]; then
       rustup component add rustfmt-preview
     else