some more dependency cleanup

.github/workflows/ci.yml

@@ -5,12 +5,25 @@ name: ci
 jobs:
   check:
     name: Check
+    os: [ubuntu-latest, macos-latest, windows-latest]
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+      - uses: actions-rs/cargo@v1
+        with:
+          command: check
+          args: --release
+
+  cross-check:
+    name: Check Cross
     runs-on: ubuntu-latest
     strategy:
       matrix:
         target:
           - armv7-unknown-linux-gnueabihf
-          - x86_64-unknown-linux-gnu
           - thumbv7em-none-eabihf
     steps:
       - uses: actions/checkout@v2
@@ -23,8 +36,8 @@ jobs:
       - uses: actions-rs/cargo@v1
         with:
           use-cross: true
-          command: build
-          args: --release --target=${{ matrix.target }}
+          command: check
+          args: --release --target=${{ matrix.target }} --no-default-features
 
   fmt:
     name: Rustfmt