Merge #96: cmake: Improve Ccache usage on Windows

6edbb28 fixup! ci: Test CMake edge cases (Hennadii Stepanov)
bbc1c4c fixup! cmake: Add `ccache` support (Hennadii Stepanov)

Pull request description:

  This PR:

  1. Improves the user experience when using the `ccache` package installed via [Chocolatey](https://community.chocolatey.org/packages/ccache) on Windows. The new approach is the same as the one currently used in the master branch CI.

  2. Also fix caching for debug configurations (see https://github.com/ccache/ccache/wiki/MS-Visual-Studio#usage-with-cmake)

  3. Added caching to the "Win64 native" CI job:
  - https://github.com/hebasto/bitcoin/actions/runs/7828761172/job/21362637142

  (it might be compared with the log for the same branch, but without the first commit: https://github.com/hebasto/bitcoin/actions/runs/7828850714/job/21363047274)

Top commit has no ACKs.

Tree-SHA512: 803f3155c113a9e985c001077d9d42adc876ab5a389c4aa786d4cc6eec19054a5e37d0a17ab68d260cbd0041eb331e9742e430f82ea8f8bf34b368e037442e0f

Author: hebasto

.github/workflows/cmake.yml

@@ -406,6 +406,10 @@ jobs:
           path: ~/AppData/Local/vcpkg/archives
           key: ${{ runner.os }}-${{ runner.arch }}-vcpkg-binary-${{ hashFiles('cmake_version', 'msbuild_version', 'toolset_version', 'vcpkg.json') }}
 
+      - name: Install Ccache
+        run: |
+          choco install --yes --no-progress ccache
+
       - name: Generate build system
         run: |
           cmake -B build --preset vs2022
@@ -417,10 +421,31 @@ jobs:
           path: ~/AppData/Local/vcpkg/archives
           key: ${{ runner.os }}-${{ runner.arch }}-vcpkg-binary-${{ hashFiles('cmake_version', 'msbuild_version', 'toolset_version', 'vcpkg.json') }}
 
+      - name: Restore Ccache cache
+        id: ccache-cache
+        uses: actions/cache/restore@v4
+        with:
+          path: ~/AppData/Local/ccache
+          key: ${{ github.job }}-ccache-${{ github.run_id }}
+          restore-keys: ${{ github.job }}-ccache-
+
       - name: Build Release configuration
         run: |
+          ccache --zero-stats
           cmake --build build -j $env:NUMBER_OF_PROCESSORS --config Release
 
+      - name: Ccache stats
+        run: |
+          ccache --version | head -n 1
+          ccache --show-stats --verbose
+
+      - name: Save Ccache cache
+        uses: actions/cache/save@v4
+        if: github.event_name != 'pull_request' && steps.ccache-cache.outputs.cache-hit != 'true'
+        with:
+          path: ~/AppData/Local/ccache
+          key: ${{ github.job }}-ccache-${{ github.run_id }}
+
       - name: Test Release configuration
         run: |
           ctest --test-dir build -j $env:NUMBER_OF_PROCESSORS -C Release

cmake/optional.cmake

@@ -5,22 +5,31 @@
 # Optional features and packages.
 
 if(CCACHE)
-  find_program(CCACHE_COMMAND ccache)
+  set(ccache_hints)
+  if(MSVC AND EXISTS "$ENV{ChocolateyInstall}")
+    # Bypass a shim executable provided by Chocolatey.
+    # See https://docs.chocolatey.org/en-us/features/shim
+    file(GLOB ccache_hints "$ENV{ChocolateyInstall}/lib/ccache/tools/ccache-*")
+  endif()
+  find_program(CCACHE_COMMAND ccache HINTS ${ccache_hints})
+  unset(ccache_hints)
+
   if(CCACHE_COMMAND)
     if(MSVC)
       if(CMAKE_VERSION VERSION_GREATER_EQUAL 3.24)
         # ccache >= 4.8 requires compile batching turned off that is available since CMake 3.24.
         # See https://github.com/ccache/ccache/wiki/MS-Visual-Studio
         set(CCACHE ON)
-        set(MSVC_CCACHE_WRAPPER_CONTENT "\"${CCACHE_COMMAND}\" \"${CMAKE_CXX_COMPILER}\"")
-        set(MSVC_CCACHE_WRAPPER_FILENAME wrapped-cl.bat)
-        file(WRITE ${CMAKE_BINARY_DIR}/${MSVC_CCACHE_WRAPPER_FILENAME} "${MSVC_CCACHE_WRAPPER_CONTENT} %*")
+        file(COPY_FILE ${CCACHE_COMMAND} ${CMAKE_BINARY_DIR}/cl.exe ONLY_IF_DIFFERENT)
         list(APPEND CMAKE_VS_GLOBALS
-          "CLToolExe=${MSVC_CCACHE_WRAPPER_FILENAME}"
+          "CLToolExe=cl.exe"
           "CLToolPath=${CMAKE_BINARY_DIR}"
           "DebugInformationFormat=OldStyle"
         )
         set(CMAKE_VS_NO_COMPILE_BATCHING ON)
+        # By default Visual Studio generators will use /Zi which is not compatible
+        # with ccache, so tell Visual Studio to use /Z7 instead.
+        set(CMAKE_MSVC_DEBUG_INFORMATION_FORMAT "$<$<CONFIG:Debug,RelWithDebInfo>:Embedded>")
       elseif(CCACHE STREQUAL "AUTO")
         message(WARNING "ccache requested and found, but CMake >= 3.24 is required to use it properly. Disabling.\n"
                         "To skip ccache check, use \"-DCCACHE=OFF\".\n")