ci: use sccache on windows instead of ccache (ggml-org#11545)

* Use sccache on ci for windows

* Detect sccache in cmake

Author: ochafik

.github/workflows/build.yml

@@ -689,6 +689,7 @@ jobs:
         uses: hendrikmuhs/ccache-action@v1.2.16
         with:
           key: windows-msys2
+          variant: sccache
           evict-old-files: 1d
 
       - name: Setup ${{ matrix.sys }}
@@ -763,6 +764,7 @@ jobs:
         uses: hendrikmuhs/ccache-action@v1.2.16
         with:
           key: windows-latest-cmake-${{ matrix.build }}
+          variant: sccache
           evict-old-files: 1d
 
       - name: Clone Kompute submodule
@@ -949,6 +951,7 @@ jobs:
         uses: hendrikmuhs/ccache-action@v1.2.16
         with:
           key: ${{ github.job }}-${{ matrix.cuda }}-${{ matrix.build }}
+          variant: sccache
           evict-old-files: 1d
 
       - name: Install Cuda Toolkit 11.7
@@ -1090,6 +1093,7 @@ jobs:
         uses: hendrikmuhs/ccache-action@v1.2.16
         with:
           key: windows-latest-cmake-sycl
+          variant: sccache
           evict-old-files: 1d
 
       - name: Install
@@ -1174,6 +1178,7 @@ jobs:
         uses: hendrikmuhs/ccache-action@v1.2.16
         with:
           key: ${{ github.job }}
+          variant: sccache
           evict-old-files: 1d
 
       - name: Build
@@ -1208,6 +1213,7 @@ jobs:
         uses: hendrikmuhs/ccache-action@v1.2.16
         with:
           key: windows-latest-cmake-hip-release
+          variant: sccache
           evict-old-files: 1d
 
       - name: Install

ggml/src/CMakeLists.txt

@@ -93,12 +93,18 @@ endif()
 
 if (GGML_CCACHE)
     find_program(GGML_CCACHE_FOUND ccache)
+    find_program(GGML_SCCACHE_FOUND sccache)
 
-    if (GGML_CCACHE_FOUND)
+    if (GGML_CCACHE_FOUND OR GGML_SCCACHE_FOUND)
+        if(GGML_CCACHE_FOUND)
+            set(GGML_CCACHE_VARIANT ccache)
+        else()
+            set(GGML_CCACHE_VARIANT sccache)
+        endif()
         # TODO: should not be set globally
-        set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE ccache)
+        set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE "${GGML_CCACHE_VARIANT}")
         set(ENV{CCACHE_SLOPPINESS} time_macros)
-        message(STATUS "ccache found, compilation results will be cached. Disable with GGML_CCACHE=OFF.")
+        message(STATUS "${GGML_CCACHE_VARIANT} found, compilation results will be cached. Disable with GGML_CCACHE=OFF.")
     else()
         message(STATUS "Warning: ccache not found - consider installing it for faster compilation or disable this warning with GGML_CCACHE=OFF")
     endif ()