diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5397cb0a6..e7ba0b6f6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -141,7 +141,7 @@ jobs:
         uses: actions/cache@v1
         with:
           path: examples/cpp/benchmark
-          key: ${{ runner.os }}-googlebenchmark-${{ hashFiles('examples/cpp/bench.cpp') }}
+          key: ${{ runner.os }}-googlebenchmark-v1.5.0
       - name: Run benchmark
         run: |
           cd examples/cpp
diff --git a/.github/workflows/cpp.yml b/.github/workflows/cpp.yml
index 52d9778aa..d7810a574 100644
--- a/.github/workflows/cpp.yml
+++ b/.github/workflows/cpp.yml
@@ -19,7 +19,7 @@ jobs:
         uses: actions/cache@v1
         with:
           path: examples/cpp/benchmark
-          key: ${{ runner.os }}-googlebenchmark-${{ hashFiles('examples/cpp/bench.cpp') }}
+          key: ${{ runner.os }}-googlebenchmark-v1.5.0
       - name: Run benchmark
         run: cd examples/cpp && make json
       - name: Store benchmark result
diff --git a/examples/cpp/Makefile b/examples/cpp/Makefile
index 30dfa7bd3..2d5f6d6f0 100644
--- a/examples/cpp/Makefile
+++ b/examples/cpp/Makefile
@@ -16,10 +16,10 @@ benchmark/build: benchmark
 	mkdir -p benchmark/build
 
 benchmark:
-	[ -d benchmark ] || git clone --depth=1 --single-branch https://github.com/google/benchmark.git benchmark
+	[ -d benchmark ] || git clone --depth=1 --single-branch --branch v1.5.0 https://github.com/google/benchmark.git benchmark
 
 benchmark/googletest: benchmark
-	[ -d benchmark/googletest ] || git clone --depth=1 --single-branch https://github.com/google/googletest.git benchmark/googletest
+	[ -d benchmark/googletest ] || git clone --depth=1 --single-branch --branch release-1.10.0 https://github.com/google/googletest.git benchmark/googletest
 
 clean:
 	rm -rf a.out benchmark