[src/trunk]: src/usr.bin/xlint/lint1 lint: fix 3 of the 4 wrong messages abou...

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

details:   https://anonhg.NetBSD.org/src/rev/3193e60f1e4d
branches:  trunk
changeset: 1022877:3193e60f1e4d
user:      rillig <rillig%NetBSD.org@localhost>
date:      Tue Aug 10 20:43:12 2021 +0000

description:
lint: fix 3 of the 4 wrong messages about lvalue in initial assignment

diffstat:

 tests/usr.bin/xlint/lint1/msg_115.c   |  11 ++++-------
 tests/usr.bin/xlint/lint1/msg_115.exp |   3 ---
 usr.bin/xlint/lint1/decl.c            |  12 +++++++++---
 usr.bin/xlint/lint1/init.c            |   5 +++--
 usr.bin/xlint/lint1/tree.c            |  21 +++++++++------------
 5 files changed, 25 insertions(+), 27 deletions(-)

diffs (183 lines):

diff -r c30202620131 -r 3193e60f1e4d tests/usr.bin/xlint/lint1/msg_115.c
--- a/tests/usr.bin/xlint/lint1/msg_115.c       Tue Aug 10 19:52:14 2021 +0000
+++ b/tests/usr.bin/xlint/lint1/msg_115.c       Tue Aug 10 20:43:12 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: msg_115.c,v 1.6 2021/07/31 10:09:03 rillig Exp $       */
+/*     $NetBSD: msg_115.c,v 1.7 2021/08/10 20:43:13 rillig Exp $       */
 # 3 "msg_115.c"
 
 // Test for message: %soperand of '%s' must be modifiable lvalue [115]
@@ -30,21 +30,18 @@
        /* expect+1: warning: left operand of '=' must be modifiable lvalue [115] */
        const_member cm1 = (const_member) { 12345 };
        if (cm1.member != 0)
-               /* FIXME: In a function call, const members can be assigned. */
-               /* expect+1: warning: left operand of 'farg' must be modifiable lvalue [115] */
+               /* In a function call, const members can be assigned. */
                take_const_member(cm1);
 
        struct {
                const_member member;
        } cm2 = {
-           /* FIXME: In an initialization, const members can be assigned. */
-           /* expect+1: warning: left operand of 'init' must be modifiable lvalue [115] */
+           /* In an initialization, const members can be assigned. */
            cm1,
        };
        if (cm2.member.member != 0) {
        }
 
-       /* FIXME: In a return statement, const members can be assigned. */
-       /* expect+1: warning: left operand of 'return' must be modifiable lvalue [115] */
+       /* In a return statement, const members can be assigned. */
        return cm1;
 }
diff -r c30202620131 -r 3193e60f1e4d tests/usr.bin/xlint/lint1/msg_115.exp
--- a/tests/usr.bin/xlint/lint1/msg_115.exp     Tue Aug 10 19:52:14 2021 +0000
+++ b/tests/usr.bin/xlint/lint1/msg_115.exp     Tue Aug 10 20:43:12 2021 +0000
@@ -6,6 +6,3 @@
 msg_115.c(15): warning: left operand of '%=' must be modifiable lvalue [115]
 msg_115.c(16): warning: operand of 'x++' must be modifiable lvalue [115]
 msg_115.c(31): warning: left operand of '=' must be modifiable lvalue [115]
-msg_115.c(35): warning: left operand of 'farg' must be modifiable lvalue [115]
-msg_115.c(42): warning: left operand of 'init' must be modifiable lvalue [115]
-msg_115.c(49): warning: left operand of 'return' must be modifiable lvalue [115]
diff -r c30202620131 -r 3193e60f1e4d usr.bin/xlint/lint1/decl.c
--- a/usr.bin/xlint/lint1/decl.c        Tue Aug 10 19:52:14 2021 +0000
+++ b/usr.bin/xlint/lint1/decl.c        Tue Aug 10 20:43:12 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: decl.c,v 1.220 2021/08/10 19:52:14 rillig Exp $ */
+/* $NetBSD: decl.c,v 1.221 2021/08/10 20:43:12 rillig Exp $ */
 
 /*
  * Copyright (c) 1996 Christopher G. Demetriou.  All Rights Reserved.
@@ -38,7 +38,7 @@
 
 #include <sys/cdefs.h>
 #if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: decl.c,v 1.220 2021/08/10 19:52:14 rillig Exp $");
+__RCSID("$NetBSD: decl.c,v 1.221 2021/08/10 20:43:12 rillig Exp $");
 #endif
 
 #include <sys/param.h>
@@ -209,7 +209,13 @@
        ntp->t_const = false;
        ntp->t_volatile = false;
 
-       /* TODO: deep-copy struct/union members; see msg_115.c */
+       /*
+        * In case of a struct or union type, the members should lose their
+        * qualifiers as well, but that would require a deep copy of the
+        * struct or union type.  This in turn would defeat the type
+        * comparison in eqtype, which simply tests whether tp1->t_str ==
+        * tp2->t_str.
+        */
 
        return ntp;
 }
diff -r c30202620131 -r 3193e60f1e4d usr.bin/xlint/lint1/init.c
--- a/usr.bin/xlint/lint1/init.c        Tue Aug 10 19:52:14 2021 +0000
+++ b/usr.bin/xlint/lint1/init.c        Tue Aug 10 20:43:12 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: init.c,v 1.206 2021/07/31 19:07:52 rillig Exp $        */
+/*     $NetBSD: init.c,v 1.207 2021/08/10 20:43:12 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 1.206 2021/07/31 19:07:52 rillig Exp $");
+__RCSID("$NetBSD: init.c,v 1.207 2021/08/10 20:43:12 rillig Exp $");
 #endif
 
 #include <stdlib.h>
@@ -833,6 +833,7 @@
        ln = build_name(in->in_sym, 0);
        ln->tn_type = expr_unqualified_type(ln->tn_type);
 
+       /* TODO: allow 'const' on the left-hand side; see msg_115.c */
        tn = build_binary(ln, ASSIGN, rn);
        expr(tn, false, false, false, false);
 
diff -r c30202620131 -r 3193e60f1e4d usr.bin/xlint/lint1/tree.c
--- a/usr.bin/xlint/lint1/tree.c        Tue Aug 10 19:52:14 2021 +0000
+++ b/usr.bin/xlint/lint1/tree.c        Tue Aug 10 20:43:12 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: tree.c,v 1.331 2021/08/09 20:07:23 rillig Exp $        */
+/*     $NetBSD: tree.c,v 1.332 2021/08/10 20:43:12 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 1.331 2021/08/09 20:07:23 rillig Exp $");
+__RCSID("$NetBSD: tree.c,v 1.332 2021/08/10 20:43:12 rillig Exp $");
 #endif
 
 #include <float.h>
@@ -1048,8 +1048,11 @@
 }
 
 static bool
-typeok_assign(const mod_t *mp, const tnode_t *ln, const type_t *ltp, tspec_t lt)
+typeok_assign(op_t op, const tnode_t *ln, const type_t *ltp, tspec_t lt)
 {
+       if (op == RETURN || op == INIT || op == FARG)
+               return true;
+
        if (!ln->tn_lvalue) {
                if (ln->tn_op == CVT && ln->tn_cast &&
                    ln->tn_left->tn_op == LOAD) {
@@ -1057,19 +1060,17 @@
                        error(163);
                }
                /* %soperand of '%s' must be lvalue */
-               error(114, "left ", mp->m_name);
+               error(114, "left ", op_name(op));
                return false;
        } else if (ltp->t_const || ((lt == STRUCT || lt == UNION) &&
                                    has_constant_member(ltp))) {
                if (!tflag)
                        /* %soperand of '%s' must be modifiable lvalue */
-                       warning(115, "left ", mp->m_name);
+                       warning(115, "left ", op_name(op));
        }
        return true;
 }
 
-
-
 /* Check the types using the information from modtab[]. */
 static bool
 typeok_scalar(op_t op, const mod_t *mp,
@@ -1223,7 +1224,7 @@
        case ORASS:
                goto assign;
        assign:
-               if (!typeok_assign(mp, ln, ltp, lt))
+               if (!typeok_assign(op, ln, ltp, lt))
                        return false;
                break;
        case COMMA:
@@ -3792,9 +3793,6 @@
        }
 }
 
-/*
- * Called by expr() to recursively perform some tests.
- */
 /* ARGSUSED */
 void
 check_expr_misc(const tnode_t *tn, bool vctx, bool tctx,
@@ -3974,7 +3972,6 @@
                            szof);
                break;
        }
-
 }
 
 /*