fix up .travis.yml

japaric · japaric · commit db82c999402a · 2018-05-10T09:48:28.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -12,7 +12,7 @@ matrix:
       rust: beta
 
     - env: TARGET=x86_64-unknown-linux-gnu
-      rust:
+      rust: nightly
 
     - env: TARGET=thumbv6m-none-eabi
       rust: nightly
