diff --git a/cmake/os/Windows.cmake b/cmake/os/Windows.cmake
index f1f483dfb33..7c2cb535f50 100644
--- a/cmake/os/Windows.cmake
+++ b/cmake/os/Windows.cmake
@@ -191,3 +191,5 @@ CHECK_TYPE_SIZE(ssize_t SIZE_OF_SSIZE_T)
 IF(NOT HAVE_SIZE_OF_SSIZE_T)
  SET(ssize_t SSIZE_T)
 ENDIF()
+
+SET(FN_NO_CASE_SENSE 1)
\ No newline at end of file
diff --git a/config.h.cmake b/config.h.cmake
index ef2207bbb91..eb1a5e24ec8 100644
--- a/config.h.cmake
+++ b/config.h.cmake
@@ -567,6 +567,9 @@
 #cmakedefine USE_MB_IDENT 1
 #cmakedefine USE_STRCOLL 1
 
+/* This should mean case insensitive file system */
+#cmakedefine FN_NO_CASE_SENSE 1
+
 #cmakedefine HAVE_CHARSET_armscii8 1
 #cmakedefine HAVE_CHARSET_ascii 
 #cmakedefine HAVE_CHARSET_big5 1