diff --git a/source/common/ucnv.h b/source/common/ucnv.h
index 31b34306622..aaa513ec4b0 100644
--- a/source/common/ucnv.h
+++ b/source/common/ucnv.h
@@ -26,6 +26,8 @@
 #include "ucnv_bld.h"
 #include "ucnv_err.h"
 
+U_CDECL_BEGIN
+
 typedef void (*UConverterToUCallback) (UConverter *,
 				  UChar **,
 				  const UChar *,
@@ -44,6 +46,8 @@ typedef void (*UConverterFromUCallback) (UConverter *,
 				    bool_t,
 				    UErrorCode *);
 
+U_CDECL_END
+
 
 /**
  * Creates a UConverter object with the names specified as a C string.