diff --git a/cmake/QtBuildInternals/QtBuildInternalsConfig.cmake b/cmake/QtBuildInternals/QtBuildInternalsConfig.cmake
index d3e3754e6f1..91275f58993 100644
--- a/cmake/QtBuildInternals/QtBuildInternalsConfig.cmake
+++ b/cmake/QtBuildInternals/QtBuildInternalsConfig.cmake
@@ -283,7 +283,7 @@ function(qt_compute_relative_path_from_cmake_config_dir_to_prefix)
     endif()
     file(RELATIVE_PATH
          qt_path_from_cmake_config_dir_to_prefix
-         ${clean_config_prefix} ${CMAKE_INSTALL_PREFIX})
+         "${clean_config_prefix}" "${CMAKE_INSTALL_PREFIX}")
      set(qt_path_from_cmake_config_dir_to_prefix "${qt_path_from_cmake_config_dir_to_prefix}"
          PARENT_SCOPE)
 endfunction()
diff --git a/src/corelib/CMakeLists.txt b/src/corelib/CMakeLists.txt
index 62cf6ec1bb3..269891f91ad 100644
--- a/src/corelib/CMakeLists.txt
+++ b/src/corelib/CMakeLists.txt
@@ -14,7 +14,7 @@ else()
     get_filename_component(_clean_prefix "${QT_CONFIG_BUILD_DIR}" ABSOLUTE)
 endif()
 file(RELATIVE_PATH QT_INVERSE_CONFIG_INSTALL_DIR
-    ${_clean_prefix} ${QT_BUILD_INTERNALS_RELOCATABLE_INSTALL_PREFIX})
+    "${_clean_prefix}" "${QT_BUILD_INTERNALS_RELOCATABLE_INSTALL_PREFIX}")
 
 # special case end