diff --git a/.github/workflows/compilers.yml b/.github/workflows/compilers.yml
index 1ccc5dbbc8..340dd20f57 100644
--- a/.github/workflows/compilers.yml
+++ b/.github/workflows/compilers.yml
@@ -257,6 +257,8 @@ jobs:
       - run: make test-all TESTS='-- ruby -ext-'
         if: ${{ matrix.entry.check }}
       - run: make test-spec
+        env:
+          CHECK_LEAKS: true
         if: ${{ matrix.entry.check }}
       - run: make test-annocheck
         if: ${{ matrix.entry.check && endsWith(matrix.entry.name, 'annocheck') }}
diff --git a/.github/workflows/spec_guards.yml b/.github/workflows/spec_guards.yml
index d09f1a24d3..7bffe25bb2 100644
--- a/.github/workflows/spec_guards.yml
+++ b/.github/workflows/spec_guards.yml
@@ -40,6 +40,8 @@ jobs:
       - run: gem install webrick
       - run: ruby ../mspec/bin/mspec
         working-directory: spec/ruby
+        env:
+          CHECK_LEAKS: true
       - uses: k0kubun/action-slack@v2.0.0
         with:
           payload: |