try a target that doesn't have std at all

Author: cuviper

.travis.yml

@@ -6,6 +6,14 @@ rust:
   - stable
   - beta
   - nightly
+matrix:
+  include:
+    # try a target that doesn't have std at all
+    - rust: stable
+      env: TARGET=thumbv6m-none-eabi
+      script:
+        - rustup target add $TARGET
+        - cargo build --verbose --target $TARGET --no-default-features
 sudo: false
 script:
   - cargo build --verbose