Add VKB_BUILD_SHADERS cmake option to control shader build (#1528)

* Add VKB_BUILD_SHADERS cmake variable to control shader compilation

* Add VKB_BUILD_SHADERS=OFF to iOS CI build script

Author: SRSaunders

.github/workflows/build.yml

@@ -194,5 +194,5 @@ jobs:
       - name: build_ios
         run: |
           source ~/VulkanSDK/iOS/setup-env.sh
-          cmake -H"." -B"build/ios" -DVKB_BUILD_TESTS=ON -DVKB_BUILD_SAMPLES=ON -G Xcode -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_DEPLOYMENT_TARGET=16.3 -DCMAKE_XCODE_ATTRIBUTE_CODE_SIGNING_ALLOWED=NO
+          cmake -H"." -B"build/ios" -DVKB_BUILD_TESTS=ON -DVKB_BUILD_SAMPLES=ON -DVKB_BUILD_SHADERS=OFF -G Xcode -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_DEPLOYMENT_TARGET=16.3 -DCMAKE_XCODE_ATTRIBUTE_CODE_SIGNING_ALLOWED=NO
           cmake --build "build/ios" --target vulkan_samples --config ${{ matrix.build_type }} -- -allowProvisioningUpdates

bldsys/cmake/global_options.cmake

@@ -120,6 +120,7 @@ set(VKB_VALIDATION_LAYERS_BEST_PRACTICES OFF CACHE BOOL "Enable best practices v
 set(VKB_VALIDATION_LAYERS_SYNCHRONIZATION OFF CACHE BOOL "Enable synchronization validation layers for every application (implicitly enables VKB_VALIDATION_LAYERS).")
 set(VKB_VULKAN_DEBUG ON CACHE BOOL "Enable VK_EXT_debug_utils or VK_EXT_debug_marker if supported.")
 set(VKB_BUILD_SAMPLES ON CACHE BOOL "Enable generation and building of Vulkan best practice samples.")
+set(VKB_BUILD_SHADERS ON CACHE BOOL "Enable shader compilation for all supported shading languages.")
 set(VKB_BUILD_TESTS OFF CACHE BOOL "Enable generation and building of Vulkan best practice tests.")
 set(VKB_WSI_SELECTION "XCB" CACHE STRING "Select WSI target (XCB, XLIB, WAYLAND, D2D)")
 set(VKB_CLANG_TIDY OFF CACHE STRING "Use CMake Clang Tidy integration")

bldsys/cmake/sample_helper.cmake

@@ -1,7 +1,7 @@
 #[[
- Copyright (c) 2019-2025, Arm Limited and Contributors
- Copyright (c) 2024-2025, Mobica Limited
- Copyright (c) 2024-2025, Sascha Willems
+ Copyright (c) 2019-2026, Arm Limited and Contributors
+ Copyright (c) 2024-2026, Mobica Limited
+ Copyright (c) 2024-2026, Sascha Willems
 
  SPDX-License-Identifier: Apache-2.0
 
@@ -197,7 +197,7 @@ endif()
     endif()
 
     # HLSL compilation via DXC
-    if(Vulkan_dxc_EXECUTABLE AND DEFINED SHADERS_HLSL)
+    if(VKB_BUILD_SHADERS AND Vulkan_dxc_EXECUTABLE AND DEFINED SHADERS_HLSL)
         set(OUTPUT_FILES "")
         set(HLSL_TARGET_NAME ${PROJECT_NAME}-HLSL)
         foreach(SHADER_FILE_HLSL ${TARGET_SHADERS_HLSL})
@@ -256,16 +256,7 @@ endif()
     endif()
 
     # Slang shader compilation
-    # Skip on MacOS/iOS due to CI/CD using potentially broken slang compiler versions from the SDK
-    # Might revisit once Slang shipped with the SDK is usable
-    set(SLANG_SKIP_COMPILE false)
-    if (($ENV{CI} MATCHES true) AND ((CMAKE_SYSTEM_NAME MATCHES "Darwin") OR (CMAKE_SYSTEM_NAME MATCHES "iOS")))
-        set(SLANG_SKIP_COMPILE true)
-    endif()
-    if(VKB_SKIP_SLANG_SHADER_COMPILATION)
-        set(SLANG_SKIP_COMPILE true)
-    endif()
-    if(NOT SLANG_SKIP_COMPILE AND Vulkan_slang_EXECUTABLE AND DEFINED SHADERS_SLANG)
+    if(VKB_BUILD_SHADERS AND NOT VKB_SKIP_SLANG_SHADER_COMPILATION AND Vulkan_slang_EXECUTABLE AND DEFINED SHADERS_SLANG)
         set(OUTPUT_FILES "")
         set(SLANG_TARGET_NAME ${PROJECT_NAME}-SLANG)
         foreach(SHADER_FILE_SLANG ${TARGET_SHADERS_SLANG})
@@ -297,7 +288,7 @@ endif()
     endif()
 
     # GLSL shader compilation
-    if(Vulkan_glslc_EXECUTABLE AND DEFINED SHADERS_GLSL)
+    if(VKB_BUILD_SHADERS AND Vulkan_glslc_EXECUTABLE AND DEFINED SHADERS_GLSL)
         set(GLSL_TARGET_NAME ${PROJECT_NAME}-GLSL)
         set(OUTPUT_FILES "")
         foreach(SHADER_FILE_GLSL ${TARGET_SHADERS_GLSL})
@@ -343,7 +334,7 @@ endif()
     endif()
 
     # spvasm shader compilation
-    if(Vulkan_spirvas_EXECUTABLE AND DEFINED SHADERS_SPVASM)
+    if(VKB_BUILD_SHADERS AND Vulkan_spirvas_EXECUTABLE AND DEFINED SHADERS_SPVASM)
         set(SPVASM_TARGET_NAME ${PROJECT_NAME}-SPVASM)
         set(OUTPUT_FILES "")
         foreach(SHADER_FILE_SPVASM ${TARGET_SHADERS_SPVASM})