diff --git a/libcxx/test/CMakeLists.txt b/libcxx/test/CMakeLists.txt
--- a/libcxx/test/CMakeLists.txt
+++ b/libcxx/test/CMakeLists.txt
@@ -117,6 +117,12 @@
   serialize_lit_param(enable_32bit True)
 endif()
 
+foreach(param IN LISTS LIBCXX_TEST_PARAMS)
+  string(REGEX REPLACE "(.+)=(.+)" "\\1" name "${param}")
+  string(REGEX REPLACE "(.+)=(.+)" "\\2" value "${param}")
+  serialize_lit_param("${name}" "\"${value}\"")
+endforeach()
+
 if (NOT DEFINED LIBCXX_TEST_DEPS)
   message(FATAL_ERROR "Expected LIBCXX_TEST_DEPS to be defined")
 endif()
@@ -136,8 +142,7 @@
   add_lit_testsuite(check-cxx
     "Running libcxx tests"
     ${CMAKE_CURRENT_BINARY_DIR}
-    DEPENDS cxx-test-depends
-    PARAMS "${LIBCXX_TEST_PARAMS}")
+    DEPENDS cxx-test-depends)
 endif()
 
 if (LIBCXX_GENERATE_COVERAGE)
diff --git a/libcxxabi/test/CMakeLists.txt b/libcxxabi/test/CMakeLists.txt
--- a/libcxxabi/test/CMakeLists.txt
+++ b/libcxxabi/test/CMakeLists.txt
@@ -94,6 +94,12 @@
   serialize_lit_param(enable_32bit True)
 endif()
 
+foreach(param IN LISTS LIBCXXABI_TEST_PARAMS)
+  string(REGEX REPLACE "(.+)=(.+)" "\\1" name "${param}")
+  string(REGEX REPLACE "(.+)=(.+)" "\\2" value "${param}")
+  serialize_lit_param("${name}" "\"${value}\"")
+endforeach()
+
 configure_lit_site_cfg(
   "${LIBCXXABI_TEST_CONFIG}"
   ${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg
@@ -101,5 +107,4 @@
 
 add_lit_testsuite(check-cxxabi "Running libcxxabi tests"
   ${CMAKE_CURRENT_BINARY_DIR}
-  DEPENDS ${LIBCXXABI_TEST_DEPS}
-  PARAMS "${LIBCXXABI_TEST_PARAMS}")
+  DEPENDS ${LIBCXXABI_TEST_DEPS})
diff --git a/libunwind/test/CMakeLists.txt b/libunwind/test/CMakeLists.txt
--- a/libunwind/test/CMakeLists.txt
+++ b/libunwind/test/CMakeLists.txt
@@ -44,6 +44,12 @@
   serialize_lit_param(enable_32bit True)
 endif()
 
+foreach(param IN LISTS LIBUNWIND_TEST_PARAMS)
+  string(REGEX REPLACE "(.+)=(.+)" "\\1" name "${param}")
+  string(REGEX REPLACE "(.+)=(.+)" "\\2" value "${param}")
+  serialize_lit_param("${name}" "\"${value}\"")
+endforeach()
+
 configure_lit_site_cfg(
   "${LIBUNWIND_TEST_CONFIG}"
   ${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg
@@ -51,5 +57,4 @@
 
 add_lit_testsuite(check-unwind "Running libunwind tests"
   ${CMAKE_CURRENT_BINARY_DIR}
-  DEPENDS unwind ${LIBUNWIND_TEST_DEPS}
-  PARAMS "${LIBUNWIND_TEST_PARAMS}")
+  DEPENDS unwind ${LIBUNWIND_TEST_DEPS})