[src/trunk]: src/usr.bin/xlint/lint1 lint: remove remaining support for lvalu...

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

details:   https://anonhg.NetBSD.org/src/rev/139e73ec36c9
branches:  trunk
changeset: 984351:139e73ec36c9
user:      rillig <rillig%NetBSD.org@localhost>
date:      Sun Jul 04 13:14:53 2021 +0000

description:
lint: remove remaining support for lvalue casts

These had been GCC extensions until GCC 3.4, they were removed in GCC
4.0.

diffstat:

 distrib/sets/lists/tests/mi              |   3 ++-
 tests/usr.bin/xlint/lint1/Makefile       |   3 ++-
 tests/usr.bin/xlint/lint1/d_cast_lhs.c   |  27 +++++++++++++++++++--------
 tests/usr.bin/xlint/lint1/d_cast_lhs.exp |   4 ++++
 usr.bin/xlint/lint1/tree.c               |   8 ++------
 5 files changed, 29 insertions(+), 16 deletions(-)

diffs (119 lines):

diff -r 74a83461688c -r 139e73ec36c9 distrib/sets/lists/tests/mi
--- a/distrib/sets/lists/tests/mi       Sun Jul 04 12:57:48 2021 +0000
+++ b/distrib/sets/lists/tests/mi       Sun Jul 04 13:14:53 2021 +0000
@@ -1,4 +1,4 @@
-# $NetBSD: mi,v 1.1074 2021/07/04 08:19:05 rillig Exp $
+# $NetBSD: mi,v 1.1075 2021/07/04 13:14:53 rillig Exp $
 #
 # Note: don't delete entries from here - mark them as "obsolete" instead.
 #
@@ -6151,6 +6151,7 @@
 ./usr/tests/usr.bin/xlint/lint1/d_cast_init.c                  tests-usr.bin-tests     compattestfile,atf
 ./usr/tests/usr.bin/xlint/lint1/d_cast_init2.c                 tests-usr.bin-tests     compattestfile,atf
 ./usr/tests/usr.bin/xlint/lint1/d_cast_lhs.c                   tests-usr.bin-tests     compattestfile,atf
+./usr/tests/usr.bin/xlint/lint1/d_cast_lhs.exp                 tests-usr.bin-tests     compattestfile,atf
 ./usr/tests/usr.bin/xlint/lint1/d_cast_typeof.c                        tests-usr.bin-tests     compattestfile,atf
 ./usr/tests/usr.bin/xlint/lint1/d_compound_literals1.c         tests-usr.bin-tests     compattestfile,atf
 ./usr/tests/usr.bin/xlint/lint1/d_compound_literals2.c         tests-usr.bin-tests     compattestfile,atf
diff -r 74a83461688c -r 139e73ec36c9 tests/usr.bin/xlint/lint1/Makefile
--- a/tests/usr.bin/xlint/lint1/Makefile        Sun Jul 04 12:57:48 2021 +0000
+++ b/tests/usr.bin/xlint/lint1/Makefile        Sun Jul 04 13:14:53 2021 +0000
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.77 2021/07/04 08:50:26 rillig Exp $
+# $NetBSD: Makefile,v 1.78 2021/07/04 13:14:54 rillig Exp $
 
 NOMAN=         # defined
 MAX_MESSAGE=   345             # see lint1/err.c
@@ -55,6 +55,7 @@
 FILES+=                d_cast_init.c
 FILES+=                d_cast_init2.c
 FILES+=                d_cast_lhs.c
+FILES+=                d_cast_lhs.exp
 FILES+=                d_cast_typeof.c
 FILES+=                d_compound_literals1.c
 FILES+=                d_compound_literals2.c
diff -r 74a83461688c -r 139e73ec36c9 tests/usr.bin/xlint/lint1/d_cast_lhs.c
--- a/tests/usr.bin/xlint/lint1/d_cast_lhs.c    Sun Jul 04 12:57:48 2021 +0000
+++ b/tests/usr.bin/xlint/lint1/d_cast_lhs.c    Sun Jul 04 13:14:53 2021 +0000
@@ -1,18 +1,29 @@
-/*     $NetBSD: d_cast_lhs.c,v 1.4 2021/03/27 13:59:18 rillig Exp $    */
+/*     $NetBSD: d_cast_lhs.c,v 1.5 2021/07/04 13:14:54 rillig Exp $    */
 # 3 "d_cast_lhs.c"
 
 /*
- * pointer casts are valid lhs lvalues
+ * Pointer casts had been valid lvalues in GCC before 4.0.
+ *
+ * https://gcc.gnu.org/onlinedocs/gcc-3.4.6/gcc/Lvalues.html#Lvalues
  *
- * XXX: C99 6.5.4 "Cast operators" footnote 85 says "A cast does not yield an
- * lvalue".  It does not mention any exceptional rule for pointers.
+ * C99 6.5.4 "Cast operators" footnote 85 says "A cast does not yield an
+ * lvalue".
  */
-struct sockaddr {
+struct str {
+       int member;
 };
 
+void sink(const void *);
+
+/* ARGSUSED */
 void
-foo()
+foo(void *p)
 {
-       unsigned long p = 6;
-       ((struct sockaddr *)p) = 0;
+       /* expect+2: error: a cast does not yield an lvalue [163] */
+       /* expect+1: error: left operand of '=' must be lvalue [114] */
+       ((struct str *)p) = 0;
+
+       /* expect+2: error: a cast does not yield an lvalue [163] */
+       /* expect+1: error: operand of '&' must be lvalue [114] */
+       sink(&(const void *)p);
 }
diff -r 74a83461688c -r 139e73ec36c9 tests/usr.bin/xlint/lint1/d_cast_lhs.exp
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/usr.bin/xlint/lint1/d_cast_lhs.exp  Sun Jul 04 13:14:53 2021 +0000
@@ -0,0 +1,4 @@
+d_cast_lhs.c(24): error: a cast does not yield an lvalue [163]
+d_cast_lhs.c(24): error: left operand of '=' must be lvalue [114]
+d_cast_lhs.c(28): error: a cast does not yield an lvalue [163]
+d_cast_lhs.c(28): error: operand of '&' must be lvalue [114]
diff -r 74a83461688c -r 139e73ec36c9 usr.bin/xlint/lint1/tree.c
--- a/usr.bin/xlint/lint1/tree.c        Sun Jul 04 12:57:48 2021 +0000
+++ b/usr.bin/xlint/lint1/tree.c        Sun Jul 04 13:14:53 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: tree.c,v 1.307 2021/07/04 12:24:38 rillig Exp $        */
+/*     $NetBSD: tree.c,v 1.308 2021/07/04 13:14:54 rillig Exp $        */
 
 /*
  * Copyright (c) 1994, 1995 Jochen Pohl
@@ -37,7 +37,7 @@
 
 #include <sys/cdefs.h>
 #if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: tree.c,v 1.307 2021/07/04 12:24:38 rillig Exp $");
+__RCSID("$NetBSD: tree.c,v 1.308 2021/07/04 13:14:54 rillig Exp $");
 #endif
 
 #include <float.h>
@@ -783,8 +783,6 @@
        } else if (!tn->tn_lvalue) {
                if (tn->tn_op == CVT && tn->tn_cast &&
                    tn->tn_left->tn_op == LOAD) {
-                       if (tn->tn_type->t_tspec == PTR)
-                               return true;
                        /* a cast does not yield an lvalue */
                        error(163);
                }
@@ -1073,8 +1071,6 @@
        if (!ln->tn_lvalue) {
                if (ln->tn_op == CVT && ln->tn_cast &&
                    ln->tn_left->tn_op == LOAD) {
-                       if (ln->tn_type->t_tspec == PTR)
-                               return true;
                        /* a cast does not yield an lvalue */
                        error(163);
                }