diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a164d1786..23d20c900 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -418,7 +418,7 @@ jobs:
       - name: build
         run: |
           emcmake cmake -B build -DQJS_BUILD_LIBC=ON
-          emmake make -C build qjs_wasm -j$(getconf _NPROCESSORS_ONLN)
+          emmake make -C build qjs_wasm "-j$(getconf _NPROCESSORS_ONLN)"
       - name: result
         run: ls -lh build
   wasi:
@@ -509,7 +509,7 @@ jobs:
         run: |
           mkdir build
           cd build
-          $ANDROID_HOME/cmake/3.22.1/bin/cmake -DCMAKE_TOOLCHAIN_FILE=$ANDROID_HOME/ndk/26.0.10792818/build/cmake/android.toolchain.cmake -DCMAKE_BUILD_TYPE=Release -DANDROID_ABI="arm64-v8a" -DANDROID_PLATFORM=android-24 -DQJS_BUILD_LIBC=ON ..
+          "$ANDROID_HOME/cmake/3.22.1/bin/cmake" "-DCMAKE_TOOLCHAIN_FILE=$ANDROID_HOME/ndk/26.0.10792818/build/cmake/android.toolchain.cmake" -DCMAKE_BUILD_TYPE=Release -DANDROID_ABI="arm64-v8a" -DANDROID_PLATFORM=android-24 -DQJS_BUILD_LIBC=ON ..
       - name: Build android arm64
         run: |
           "$ANDROID_HOME/cmake/3.22.1/bin/cmake" --build build --target qjs
@@ -711,6 +711,14 @@ jobs:
             mode:
               name: sanitize
 
+          # clang's -O0 codegen is broken.
+          - flavor: debug
+            mode:
+              name: clang+sanitize
+          - flavor: debug
+            mode:
+              name: clang+msan
+
     steps:
       - name: Setup meson
         run: |