diff --git a/mingw-w64-crt/def-include/func.def.in b/mingw-w64-crt/def-include/func.def.in
index 58cc36d..a5a4efa 100644
--- a/mingw-w64-crt/def-include/func.def.in
+++ b/mingw-w64-crt/def-include/func.def.in
@@ -55,3 +55,8 @@
 #ifndef F_NON_I386
 #define F_NON_I386(x)
 #endif
+
+#if defined(DEF_I386)
+// for __cdecl and __stdcall only
+#define DECORATED_EXPORT(symbol) symbol == _ ## symbol
+#endif
diff --git a/mingw-w64-crt/def-include/msvcrt-common.def.in b/mingw-w64-crt/def-include/msvcrt-common.def.in
index 26aa13e..7f24d9a 100644
--- a/mingw-w64-crt/def-include/msvcrt-common.def.in
+++ b/mingw-w64-crt/def-include/msvcrt-common.def.in
@@ -3,9 +3,6 @@
 #define ADD_UNDERSCORE(symbol) symbol == _ ## symbol
 #define ADD_DOUBLE_UNDERSCORE(symbol) symbol == __ ## symbol
 
-// for __cdecl and __stdcall only
-#define DECORATED_EXPORT(symbol) symbol == _ ## symbol
-
 ADD_DOUBLE_UNDERSCORE(iscsymf)
 ADD_DOUBLE_UNDERSCORE(iscsym)
 ADD_DOUBLE_UNDERSCORE(isascii)