diff --git a/src/include/fmgr.h b/src/include/fmgr.h
index 4e8f68c7cebdff0a24ffde444d6a89190c509bd1..808d142bd4aa3ca0d7de482cb173e138e217628e 100644
--- a/src/include/fmgr.h
+++ b/src/include/fmgr.h
@@ -505,9 +505,9 @@ extern Datum FunctionCall9Coll(FmgrInfo *flinfo, Oid collation,
 
 /* These are for invocation of a function identified by OID with a
  * directly-computed parameter list.  Note that neither arguments nor result
- * are allowed to be NULL.  These are essentially FunctionLookup() followed
- * by FunctionCallN().  If the same function is to be invoked repeatedly,
- * do the FunctionLookup() once and then use FunctionCallN().
+ * are allowed to be NULL.  These are essentially fmgr_info() followed by
+ * FunctionCallN().  If the same function is to be invoked repeatedly, do the
+ * fmgr_info() once and then use FunctionCallN().
  */
 extern Datum OidFunctionCall0Coll(Oid functionId, Oid collation);
 extern Datum OidFunctionCall1Coll(Oid functionId, Oid collation,