diff --git a/build/cmake/setup.cmake b/build/cmake/setup.cmake
index 5656b9dc30..c3d66de91e 100644
--- a/build/cmake/setup.cmake
+++ b/build/cmake/setup.cmake
@@ -641,7 +641,10 @@ endif()
 
 if(wxUSE_XLOCALE)
     check_include_file(xlocale.h HAVE_XLOCALE_H)
-    set(CMAKE_EXTRA_INCLUDE_FILES xlocale.h locale.h)
+    set(CMAKE_EXTRA_INCLUDE_FILES locale.h)
+    if(HAVE_XLOCALE_H)
+        list(APPEND CMAKE_EXTRA_INCLUDE_FILES xlocale.h)
+    endif()
     check_type_size(locale_t LOCALE_T)
     set(CMAKE_EXTRA_INCLUDE_FILES)
 endif()