Use sccache on Windows (#4678)

* build: support sccache and windows

.github/workflows/build.yml

@@ -134,6 +134,16 @@ jobs:
           "C2_CONAN_CACHE_SUFFIX=$(if ($Env:C2_BUILD_WITH_QT6 -eq "on") { "-QT6" } else { "`" })" >> "$Env:GITHUB_ENV"
         shell: powershell
 
+      - name: Setup sccache (Windows)
+        # sccache v0.5.3
+        uses: nerixyz/ccache-action@9a7e8d00116ede600ee7717350c6594b8af6aaa5
+        if: startsWith(matrix.os, 'windows')
+        with:
+          variant: sccache
+          key: sccache-build-${{ matrix.os }}-${{ matrix.qt-version }}-${{ matrix.skip-crashpad }}
+          restore-keys: |
+            sccache-build-${{ matrix.os }}-${{ matrix.qt-version }}
+
       - name: Cache conan packages (Windows)
         if: startsWith(matrix.os, 'windows')
         uses: actions/cache@v3

.gitignore

@@ -121,3 +121,6 @@ resources/resources_autogenerated.qrc
 
 # Leftovers from running `aqt install`
 aqtinstall.log
+
+# sccache (CI)
+.sccache

CHANGELOG.md

@@ -21,6 +21,8 @@
 - Dev: Replace our QObjectRef class with Qt's QPointer class. (#4666)
 - Dev: Fixed warnings about QWidgets already having a QLayout. (#4672)
 - Dev: Fixed undefined behavior when loading non-existant credentials. (#4673)
+- Dev: Added support for compiling with `sccache`. (#4678)
+- Dev: Added `sccache` in Windows CI. (#4678)
 
 ## 2.4.4
 

CMakeLists.txt

@@ -42,11 +42,30 @@ else()
 endif()
 
 find_program(CCACHE_PROGRAM ccache)
-if (CCACHE_PROGRAM)
-    set(CMAKE_CXX_COMPILER_LAUNCHER "${CCACHE_PROGRAM}")
-    message("Using ${CCACHE_PROGRAM} for speeding up build")
+find_program(SCCACHE_PROGRAM sccache)
+if (SCCACHE_PROGRAM)
+    set(_compiler_launcher ${SCCACHE_PROGRAM})
+elseif (CCACHE_PROGRAM)
+    set(_compiler_launcher ${CCACHE_PROGRAM})
 endif ()
 
+if (_compiler_launcher)
+    set(CMAKE_CXX_COMPILER_LAUNCHER "${_compiler_launcher}" CACHE STRING "CXX compiler launcher")
+    message(STATUS "Using ${_compiler_launcher} for speeding up build")
+
+    if (MSVC)
+        # /Zi can't be used with (s)ccache
+        # Use /Z7 instead (debug info in object files)
+        if(CMAKE_BUILD_TYPE STREQUAL "Debug")
+            string(REPLACE "/Zi" "/Z7" CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG}")
+        elseif(CMAKE_BUILD_TYPE STREQUAL "Release")
+            string(REPLACE "/Zi" "/Z7" CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE}")
+        elseif(CMAKE_BUILD_TYPE STREQUAL "RelWithDebInfo")
+            string(REPLACE "/Zi" "/Z7" CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS_RELWITHDEBINFO}")
+        endif()
+    endif()
+endif()
+
 include(${CMAKE_CURRENT_LIST_DIR}/cmake/GIT.cmake)
 
 find_package(Qt${MAJOR_QT_VERSION} REQUIRED