ci : check if these changes fix Github Actions (Metal)

Author: ggerganov

.github/workflows/build.yml

@@ -171,10 +171,6 @@ jobs:
           LLAMA_NO_METAL=1 make tests -j $(sysctl -n hw.logicalcpu)
           LLAMA_NO_METAL=1 make test  -j $(sysctl -n hw.logicalcpu)
 
-  # TODO: build with LLAMA_METAL=OFF because test-backend-ops fail on "Apple Paravirtual device" and I don't know
-  #       how to debug it.
-  #       ref: https://github.com/ggerganov/llama.cpp/actions/runs/7132125951/job/19422043567?pr=4359#step:5:6584
-  #       would be great if we fix these
   macOS-latest-cmake:
     runs-on: macos-latest
 
@@ -195,7 +191,7 @@ jobs:
           sysctl -a
           mkdir build
           cd build
-          cmake -DLLAMA_METAL=OFF ..
+          cmake -DLLAMA_METAL=ON -DLLAMA_METAL_NO_FAST_MATH=ON ..
           cmake --build . --config Release -j $(sysctl -n hw.logicalcpu)
 
       - name: Test

CMakeLists.txt

@@ -184,7 +184,7 @@ if (LLAMA_METAL)
         # note: adding -fno-inline fixes the tests when using MTL_SHADER_VALIDATION=1
         add_custom_command(
             OUTPUT ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ggml.metallib
-            COMMAND xcrun -sdk macosx metal -fno-fast-math -fno-inline -c ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ggml-metal.metal -o ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ggml-metal.air
+            COMMAND xcrun -sdk macosx metal -O1 -fno-fast-math -fno-inline -c ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ggml-metal.metal -o ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ggml-metal.air
             COMMAND xcrun -sdk macosx metallib ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ggml-metal.air -o ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ggml.metallib
             DEPENDS ggml-metal.metal
             COMMENT "Compiling Metal kernels"