diff --git a/src/ldo.c b/src/ldo.c
index 086d174..8c8ba73 100644
--- a/src/ldo.c
+++ b/src/ldo.c
@@ -526,7 +526,13 @@ l_sinline int precallC (lua_State *L, StkId func, int nresults,
     luaD_hook(L, LUA_HOOKCALL, -1, 1, narg);
   }
   lua_unlock(L);
-  n = (*f)(L);  /* do the actual call */
+  /* do the actual call */
+#ifdef USE_YK
+  f = (lua_CFunction) yk_promote((void *) *f);
+  n = (f)(L);
+#else
+  n = (*f)(L);
+#endif
   lua_lock(L);
   api_checknelems(L, n);
   luaD_poscall(L, ci, n);