diff --git a/libcxxabi/test/CMakeLists.txt b/libcxxabi/test/CMakeLists.txt
--- a/libcxxabi/test/CMakeLists.txt
+++ b/libcxxabi/test/CMakeLists.txt
@@ -8,7 +8,7 @@
 endmacro()
 
 pythonize_bool(LIBCXXABI_USE_LLVM_UNWINDER)
-set(LIBCXXABI_EXECUTOR "${Python3_EXECUTABLE} ${LIBCXXABI_LIBCXX_PATH}/utils/run.py" CACHE STRING
+set(LIBCXXABI_EXECUTOR "\\\"${Python3_EXECUTABLE}\\\" ${LIBCXXABI_LIBCXX_PATH}/utils/run.py" CACHE STRING
     "Executor to use when running tests.")
 
 if (LIBCXXABI_ENABLE_SHARED)
diff --git a/libunwind/test/CMakeLists.txt b/libunwind/test/CMakeLists.txt
--- a/libunwind/test/CMakeLists.txt
+++ b/libunwind/test/CMakeLists.txt
@@ -10,7 +10,7 @@
 pythonize_bool(LIBUNWIND_ENABLE_CET)
 pythonize_bool(LIBUNWIND_ENABLE_THREADS)
 pythonize_bool(LIBUNWIND_USES_ARM_EHABI)
-set(LIBUNWIND_EXECUTOR "${Python3_EXECUTABLE} ${LIBUNWIND_LIBCXX_PATH}/utils/run.py" CACHE STRING
+set(LIBUNWIND_EXECUTOR "\\\"${Python3_EXECUTABLE}\\\" ${LIBUNWIND_LIBCXX_PATH}/utils/run.py" CACHE STRING
     "Executor to use when running tests.")
 
 set(AUTO_GEN_COMMENT "## Autogenerated by libunwind configuration.\n# Do not edit!")