[src/trunk]: src/usr.bin/xlint/lint1 lint: fix grammar for initialization

[rillig <rillig%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/9cc64140734e
branches:  trunk
changeset: 981748:9cc64140734e
user:      rillig <rillig%NetBSD.org@localhost>
date:      Sat Mar 20 11:05:16 2021 +0000

description:
lint: fix grammar for initialization

Previously, the grammar syntactically accepted the following code:

        int var = .member = 12345;

The designation '.member =' can only be used with brace-enclosed
initializers.

diffstat:

 usr.bin/xlint/lint1/cgram.y |  25 +++++++++++++++----------
 1 files changed, 15 insertions(+), 10 deletions(-)

diffs (75 lines):

diff -r 2ebdbcd6cab0 -r 9cc64140734e usr.bin/xlint/lint1/cgram.y
--- a/usr.bin/xlint/lint1/cgram.y       Sat Mar 20 10:32:43 2021 +0000
+++ b/usr.bin/xlint/lint1/cgram.y       Sat Mar 20 11:05:16 2021 +0000
@@ -1,5 +1,5 @@
 %{
-/* $NetBSD: cgram.y,v 1.179 2021/03/20 10:32:43 rillig Exp $ */
+/* $NetBSD: cgram.y,v 1.180 2021/03/20 11:05:16 rillig Exp $ */
 
 /*
  * Copyright (c) 1996 Christopher G. Demetriou.  All Rights Reserved.
@@ -35,7 +35,7 @@
 
 #include <sys/cdefs.h>
 #if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: cgram.y,v 1.179 2021/03/20 10:32:43 rillig Exp $");
+__RCSID("$NetBSD: cgram.y,v 1.180 2021/03/20 11:05:16 rillig Exp $");
 #endif
 
 #include <limits.h>
@@ -119,7 +119,7 @@
 }
 %}
 
-%expect 138
+%expect 136
 
 %union {
        int     y_int;
@@ -1326,10 +1326,6 @@
        ;
 
 initializer:                   /* C99 6.7.8 "Initialization" */
-       | designation init_base_expr    %prec T_COMMA
-       | init_base_expr
-
-init_base_expr:
          expr                          %prec T_COMMA {
                init_using_expr($1);
          }
@@ -1342,8 +1338,13 @@
        ;
 
 initializer_list:              /* C99 6.7.8 "Initialization" */
-         initializer           %prec T_COMMA
-       | initializer_list T_COMMA initializer
+         initializer_list_item         %prec T_COMMA
+       | initializer_list T_COMMA initializer_list_item
+       ;
+
+initializer_list_item:
+         designation initializer
+       | initializer
        ;
 
 range:
@@ -1978,7 +1979,7 @@
        | T_LPAREN type_name T_RPAREN                   %prec T_UNARY {
                sym_t *tmp = mktempsym($2);
                cgram_declare(tmp, true, NULL);
-         } init_lbrace initializer_list init_rbrace {
+         } init_lbrace initializer_list comma_opt init_rbrace {
                if (!Sflag)
                         /* compound literals are a C9X/GCC extension */
                         gnuism(319);
@@ -2044,6 +2045,10 @@
          }
        ;
 
+comma_opt:
+         T_COMMA
+       | /* empty */
+       ;
 %%
 
 /* ARGSUSED */