diff --git a/CMakeLists.txt b/CMakeLists.txt
index e7038f89d..c9bb2fcac 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -112,6 +112,7 @@ endif()
 add_definitions(-DFLATBUFFERS_LOCALE_INDEPENDENT=$<BOOL:${FLATBUFFERS_LOCALE_INDEPENDENT}>)
 
 if(NOT WIN32)
+  include(CheckSymbolExists)
   check_symbol_exists(realpath "stdlib.h" HAVE_REALPATH)
   if(NOT HAVE_REALPATH)
     add_definitions(-DFLATBUFFERS_NO_ABSOLUTE_PATH_RESOLUTION)