diff --git a/include/freetype/ftmodapi.h b/include/freetype/ftmodapi.h
index 8d039c4f3..88488bfe8 100644
--- a/include/freetype/ftmodapi.h
+++ b/include/freetype/ftmodapi.h
@@ -623,7 +623,7 @@ FT_BEGIN_HEADER
* it is bytecode interpreter's execution context, `TT_ExecContext`,
* which is declared in FreeType's internal header file `tttypes.h`.
*/
- typedef FT_Error
+ typedef void
(*FT_DebugHook_Func)( void* arg );