[src/trunk]: src/usr.bin/xlint/lint1 lint: do not modify tnode_t->tn_type in ...

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

details:   https://anonhg.NetBSD.org/src/rev/fe6f91531eb4
branches:  trunk
changeset: 379979:fe6f91531eb4
user:      rillig <rillig%NetBSD.org@localhost>
date:      Tue Jun 29 21:05:32 2021 +0000

description:
lint: do not modify tnode_t->tn_type in check_init_expr

This is a very small step towards having all shared type_t objects only
referenced via const pointers.  Since the types may be shared, it is a
bad idea to try to modify them, so better let the compiler check this.
It's a long way to reach this goal, but this small step is already
possible.

No functional change.

diffstat:

 usr.bin/xlint/lint1/init.c |  11 +++++++----
 1 files changed, 7 insertions(+), 4 deletions(-)

diffs (38 lines):

diff -r 2e695529d449 -r fe6f91531eb4 usr.bin/xlint/lint1/init.c
--- a/usr.bin/xlint/lint1/init.c        Tue Jun 29 21:04:02 2021 +0000
+++ b/usr.bin/xlint/lint1/init.c        Tue Jun 29 21:05:32 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: init.c,v 1.199 2021/06/19 15:23:57 rillig Exp $        */
+/*     $NetBSD: init.c,v 1.200 2021/06/29 21:05:32 rillig Exp $        */
 
 /*
  * Copyright (c) 1994, 1995 Jochen Pohl
@@ -38,7 +38,7 @@
 
 #include <sys/cdefs.h>
 #if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: init.c,v 1.199 2021/06/19 15:23:57 rillig Exp $");
+__RCSID("$NetBSD: init.c,v 1.200 2021/06/29 21:05:32 rillig Exp $");
 #endif
 
 #include <stdlib.h>
@@ -381,14 +381,17 @@ static void
 check_init_expr(const type_t *tp, sym_t *sym, tnode_t *tn)
 {
        tnode_t *ln;
+       type_t *ltp;
        tspec_t lt, rt;
        struct memory_block *tmem;
 
+       ltp = expr_dup_type(tp);
+       ltp->t_const = false;
+
        /* Create a temporary node for the left side. */
        ln = expr_zalloc(sizeof(*ln));
        ln->tn_op = NAME;
-       ln->tn_type = expr_dup_type(tp);
-       ln->tn_type->t_const = false;
+       ln->tn_type = ltp;
        ln->tn_lvalue = true;
        ln->tn_sym = sym;