[src/trunk]: src/usr.bin/xlint/lint1 lint: allow pointer cast from char to st...

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

details:   https://anonhg.NetBSD.org/src/rev/b5d9f8c7a789
branches:  trunk
changeset: 368112:b5d9f8c7a789
user:      rillig <rillig%NetBSD.org@localhost>
date:      Fri Jun 24 19:27:43 2022 +0000

description:
lint: allow pointer cast from char to struct/union

diffstat:

 tests/usr.bin/xlint/lint1/msg_247.c |  10 +++++++---
 usr.bin/xlint/lint1/tree.c          |  10 +++++-----
 2 files changed, 12 insertions(+), 8 deletions(-)

diffs (66 lines):

diff -r 18bfcbcd382b -r b5d9f8c7a789 tests/usr.bin/xlint/lint1/msg_247.c
--- a/tests/usr.bin/xlint/lint1/msg_247.c       Fri Jun 24 19:20:39 2022 +0000
+++ b/tests/usr.bin/xlint/lint1/msg_247.c       Fri Jun 24 19:27:43 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: msg_247.c,v 1.19 2022/06/24 19:20:39 rillig Exp $      */
+/*     $NetBSD: msg_247.c,v 1.20 2022/06/24 19:27:43 rillig Exp $      */
 # 3 "msg_247.c"
 
 // Test for message: pointer cast from '%s' to '%s' may be troublesome [247]
@@ -190,14 +190,18 @@
        sink(usp);
 }
 
+/*
+ * Before tree.c 1.460 from 2022-06-24, lint warned about pointer casts from
+ * unsigned char or plain char to a struct or union type.  These casts often
+ * occur in traditional code that does not use void pointers, even 30 years
+ * after C90 introduced 'void'.
+ */
 void
 char_to_struct(void *ptr)
 {
 
-       /* expect+1: warning: pointer cast from 'pointer to char' to 'pointer to struct counter' may be troublesome [247] */
        sink((struct counter *)(char *)ptr);
 
-       /* expect+1: warning: pointer cast from 'pointer to unsigned char' to 'pointer to struct counter' may be troublesome [247] */
        sink((struct counter *)(unsigned char *)ptr);
 
        /* expect+1: warning: pointer cast from 'pointer to signed char' to 'pointer to struct counter' may be troublesome [247] */
diff -r 18bfcbcd382b -r b5d9f8c7a789 usr.bin/xlint/lint1/tree.c
--- a/usr.bin/xlint/lint1/tree.c        Fri Jun 24 19:20:39 2022 +0000
+++ b/usr.bin/xlint/lint1/tree.c        Fri Jun 24 19:27:43 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: tree.c,v 1.459 2022/06/22 19:23:18 rillig Exp $        */
+/*     $NetBSD: tree.c,v 1.460 2022/06/24 19:27:43 rillig Exp $        */
 
 /*
  * Copyright (c) 1994, 1995 Jochen Pohl
@@ -37,7 +37,7 @@
 
 #include <sys/cdefs.h>
 #if defined(__RCSID)
-__RCSID("$NetBSD: tree.c,v 1.459 2022/06/22 19:23:18 rillig Exp $");
+__RCSID("$NetBSD: tree.c,v 1.460 2022/06/24 19:27:43 rillig Exp $");
 #endif
 
 #include <float.h>
@@ -2507,14 +2507,14 @@
        if (is_incomplete(nstp) || is_incomplete(ostp))
                return false;
 
-       if (is_struct_or_union(nst) && nstp->t_str != ostp->t_str)
-               return true;
-
        if (nst == CHAR || nst == UCHAR)
                return false;   /* for the sake of traditional C code */
        if (ost == CHAR || ost == UCHAR)
                return false;   /* for the sake of traditional C code */
 
+       if (is_struct_or_union(nst) && nstp->t_str != ostp->t_str)
+               return true;
+
        return portable_size_in_bits(nst) != portable_size_in_bits(ost);
 }