CMake: Add support for clcache

.appveyor.yml

@@ -9,13 +9,14 @@ environment:
     - compiler: msvc
 install:
   - vcpkg install --triplet %PLATFORM%-windows fftw3 libsamplerate libsndfile sdl2
+  - nuget install clcache -Version 4.1.0
 build_script:
   - cd %APPVEYOR_BUILD_FOLDER%
   - mkdir build
   - cd build
   - ps: $env:CMAKE_PLATFORM="$(if ($env:PLATFORM -eq 'x64') { 'x64' } else { '' })"
   - ps: $env:QT_SUFFIX="$(if ($env:PLATFORM -eq 'x64') { '_64' } else { '' })"
-  - cmake -DCMAKE_BUILD_TYPE=RelWithDebInfo -DCMAKE_PREFIX_PATH=c:/Qt/5.9.5/msvc2015%QT_SUFFIX%;c:/tools/vcpkg/installed/%PLATFORM%-windows -DCMAKE_GENERATOR_PLATFORM="%CMAKE_PLATFORM%" ..
+  - cmake -DUSE_COMPILE_CACHE=ON -DCACHE_TOOL=%APPVEYOR_BUILD_FOLDER%/clcache.4.1.0/clcache-4.1.0/clcache.exe -DCMAKE_BUILD_TYPE=RelWithDebInfo -DCMAKE_PREFIX_PATH=c:/Qt/5.9.5/msvc2015%QT_SUFFIX%;c:/tools/vcpkg/installed/%PLATFORM%-windows -DCMAKE_GENERATOR_PLATFORM="%CMAKE_PLATFORM%" ..
   - cmake --build . -- /maxcpucount:4
   - cmake --build . --target tests
 cache:

CMakeLists.txt

@@ -546,17 +546,7 @@ IF(CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
 ENDIF()
 
 # use ccache
-OPTION(USE_CCACHE "Use ccache for compilation" OFF)
-IF(USE_CCACHE)
-	FIND_PROGRAM(CCACHE ccache)
-	IF (CCACHE)
-		MESSAGE(STATUS "Using ccache found in PATH")
-		SET_PROPERTY(GLOBAL PROPERTY RULE_LAUNCH_COMPILE ${CCACHE})
-		SET_PROPERTY(GLOBAL PROPERTY RULE_LAUNCH_LINK ${CCACHE})
-	ELSE()
-		MESSAGE(WARNING "USE_CCACHE enabled, but no ccache found")
-	ENDIF()
-ENDIF()
+include(CompileCache)
 
 # make sub-directories
 ADD_SUBDIRECTORY(cmake)

cmake/modules/CompileCache.cmake

@@ -0,0 +1,25 @@
+option(USE_COMPILE_CACHE "Use ccache or clcache for compilation" OFF)
+
+# Compatibility for old option name
+if(USE_CCACHE)
+	set(USE_COMPILE_CACHE ON)
+endif()
+
+if(USE_COMPILE_CACHE)
+	if(MSVC)
+		set(CACHE_TOOL_NAME clcache)
+	elseif(CMAKE_CXX_COMPILER_ID MATCHES "(GNU|AppleClang|Clang)")
+		set(CACHE_TOOL_NAME ccache)
+	else()
+		message(WARNING "Compile cache only available with MSVC or GNU")
+	endif()
+
+	find_program(CACHE_TOOL ${CACHE_TOOL_NAME})
+	if (CACHE_TOOL)
+		message(STATUS "Using ${CACHE_TOOL} found for caching")
+		set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE ${CACHE_TOOL})
+		set_property(GLOBAL PROPERTY RULE_LAUNCH_LINK ${CACHE_TOOL})
+	else()
+		message(WARNING "USE_COMPILE_CACHE enabled, but no ${CACHE_TOOL_NAME} found")
+	endif()
+endif()