diff --git a/cmake/prebuild.cmake b/cmake/prebuild.cmake
index b0348f3a3..e508a46c2 100644
--- a/cmake/prebuild.cmake
+++ b/cmake/prebuild.cmake
@@ -59,7 +59,7 @@ set(FU "")
 if (APPLE OR (MSVC AND NOT ${CMAKE_C_COMPILER_ID} MATCHES "Clang"))
   set(FU "_")
 endif()
-if(MINGW)
+if(MINGW AND NOT MINGW64)
   set(FU "_")
 endif()