ci: don't save caches for pull requests

.github/workflows/build.yml

@@ -40,7 +40,9 @@ jobs:
       - uses: actions/checkout@v5
         with:
           submodules: recursive
-      - uses: actions/cache@v5
+      - name: restore ccache
+        uses: actions/cache/restore@v5
+        id: ccache-restore
         with:
           path: /Users/runner/Library/Caches/ccache
           key: ccache-${{ runner.os }}-build-${{ github.sha }}
@@ -57,6 +59,12 @@ jobs:
         run: |
           ${{env.CCACHE_SETTINGS}}
           ${{env.BUILD_DEFAULT}}
+      - name: save ccache
+        uses: actions/cache/save@v5
+        if: github.event_name != 'pull_request' && steps.ccache-restore.outputs.cache-hit != 'true'
+        with:
+          path: /Users/runner/Library/Caches/ccache
+          key: ${{ steps.ccache-restore.outputs.cache-primary-key }}
 
   build-windows:
     name: 'Windows (MSYS2)'
@@ -68,7 +76,9 @@ jobs:
       - uses: actions/checkout@v5
         with:
           submodules: recursive
-      - uses: actions/cache@v5
+      - name: restore ccache
+        uses: actions/cache/restore@v5
+        id: ccache-restore
         with:
           path: C:\Users\runneradmin\AppData\Local\ccache
           key: ccache-${{ runner.os }}-build-${{ github.sha }}
@@ -76,6 +86,7 @@ jobs:
       - uses: msys2/setup-msys2@v2
         with:
           update: true
+          cache: false
           install: mingw-w64-x86_64-toolchain make mingw-w64-x86_64-cmake mingw-w64-x86_64-ccache mingw-w64-x86_64-boost mingw-w64-x86_64-openssl mingw-w64-x86_64-zeromq mingw-w64-x86_64-libsodium mingw-w64-x86_64-hidapi mingw-w64-x86_64-protobuf mingw-w64-x86_64-libusb mingw-w64-x86_64-unbound mingw-w64-x86_64-rust git pkg-config
       - uses: ./.github/actions/set-make-job-count
       - name: build
@@ -84,6 +95,12 @@ jobs:
         run: |
           ${{env.CCACHE_SETTINGS}}
           ${{env.BUILD_DEFAULT}}
+      - name: save ccache
+        uses: actions/cache/save@v5
+        if: github.event_name != 'pull_request' && steps.ccache-restore.outputs.cache-hit != 'true'
+        with:
+          path: C:\Users\runneradmin\AppData\Local\ccache
+          key: ${{ steps.ccache-restore.outputs.cache-primary-key }}
 
   build-arch:
     name: 'Arch Linux'
@@ -98,7 +115,9 @@ jobs:
       - uses: actions/checkout@v5
         with:
           submodules: recursive
-      - uses: actions/cache@v5
+      - name: restore ccache
+        uses: actions/cache/restore@v5
+        id: ccache-restore
         with:
           path: ~/.cache/ccache
           key: ccache-arch-build-${{ github.sha }}
@@ -110,6 +129,12 @@ jobs:
         run: |
           ${{ env.CCACHE_SETTINGS }}
           ${{ env.BUILD_DEFAULT }}
+      - name: save ccache
+        uses: actions/cache/save@v5
+        if: github.event_name != 'pull_request' && steps.ccache-restore.outputs.cache-hit != 'true'
+        with:
+          path: ~/.cache/ccache
+          key: ${{ steps.ccache-restore.outputs.cache-primary-key }}
 
   build-debian:
     # Oldest supported Debian version
@@ -133,7 +158,9 @@ jobs:
       - uses: actions/checkout@v5
         with:
           submodules: recursive
-      - uses: actions/cache@v5
+      - name: restore ccache
+        uses: actions/cache/restore@v5
+        id: ccache-restore
         with:
           path: ~/.cache/ccache
           key: ccache-debian-11-build-${{ github.sha }}
@@ -145,6 +172,12 @@ jobs:
         run: |
           ${{ env.CCACHE_SETTINGS }}
           ${{ env.BUILD_DEFAULT }}
+      - name: save ccache
+        uses: actions/cache/save@v5
+        if: github.event_name != 'pull_request' && steps.ccache-restore.outputs.cache-hit != 'true'
+        with:
+          path: ~/.cache/ccache
+          key: ${{ steps.ccache-restore.outputs.cache-primary-key }}
 
   build-ubuntu:
     name: ${{ matrix.name }}
@@ -174,7 +207,9 @@ jobs:
       - uses: actions/checkout@v5
         with:
           submodules: recursive
-      - uses: actions/cache@v5
+      - name: restore ccache
+        uses: actions/cache/restore@v5
+        id: ccache-restore
         with:
           path: ~/.cache/ccache
           key: ccache-${{ matrix.container }}-build-${{ github.sha }}
@@ -186,6 +221,12 @@ jobs:
         run: |
           ${{env.CCACHE_SETTINGS}}
           ${{env.BUILD_DEFAULT}}
+      - name: save ccache
+        uses: actions/cache/save@v5
+        if: github.event_name != 'pull_request' && steps.ccache-restore.outputs.cache-hit != 'true'
+        with:
+          path: ~/.cache/ccache
+          key: ${{ steps.ccache-restore.outputs.cache-primary-key }}
 
   test-ubuntu:
     name: "${{ matrix.name }} (tests)"
@@ -221,7 +262,9 @@ jobs:
       - uses: actions/checkout@v5
         with:
           submodules: recursive
-      - uses: actions/cache@v5
+      - name: restore ccache
+        uses: actions/cache/restore@v5
+        id: ccache-restore
         with:
           path: ~/.cache/ccache
           key: ccache-${{ matrix.container }}-build-${{ github.sha }}
@@ -238,6 +281,12 @@ jobs:
           ${{env.CCACHE_SETTINGS}}
           ${{env.BUILD_DEFAULT}}
           cmake --build build --target test
+      - name: save ccache
+        uses: actions/cache/save@v5
+        if: github.event_name != 'pull_request' && steps.ccache-restore.outputs.cache-hit != 'true'
+        with:
+          path: ~/.cache/ccache
+          key: ${{ steps.ccache-restore.outputs.cache-primary-key }}
 
   source-archive:
     name: "source archive"