diff --git a/.github/workflows/ci_workflow.yml b/.github/workflows/ci_workflow.yml
index 66784ea93..27ddc99a7 100644
--- a/.github/workflows/ci_workflow.yml
+++ b/.github/workflows/ci_workflow.yml
@@ -66,7 +66,7 @@ jobs:
       # Source: https://github.com/AcademySoftwareFoundation/aswf-docker
       container: aswf/ci-openexr:${{ matrix.vfx-cy || 2024 }}
       cxx-standard: ${{ matrix.cxx-standard || 17 }}
-      cxx-compiler: ${{ matrix.cxx-compiler || g++ }}
+      cxx-compiler: ${{ matrix.cxx-compiler || 'g++' }}
       cc-compiler: ${{ matrix.cc-compiler || gcc }}
       build-type: ${{ matrix.build-type || Release }}
       BUILD_SHARED_LIBS: ${{ matrix.BUILD_SHARED_LIBS || ON }}