diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 2c24ebeb..cf02bbbe 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -143,7 +143,6 @@ jobs:
           cd build
           cmake -G Xcode -DCMAKE_TOOLCHAIN_FILE=../ios.toolchain.cmake -DPLATFORM=OS64 .. -DPK_BUILD_STATIC_LIB=ON -DPK_USE_CJSON=ON -DPK_USE_BOX2D=ON
           cmake --build . --config Release
-          ls -l
           cd ..
           mkdir -p output/ios
           cp build/Release-iphoneos/libpocketpy.a output/ios/libpocketpy.a
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 32825edf..9a214aef 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -27,6 +27,11 @@ elseif(MSVC)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /EHsc /utf-8 /O2")
 else()
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fexceptions -O2")
+
+    # -Wshorten-64-to-32 for apple
+    if(APPLE)
+        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wshorten-64-to-32")
+    endif()
 endif()
 
 include_directories(${CMAKE_CURRENT_LIST_DIR}/include)