Module Name: src
Committed By: rillig
Date: Sat Apr 22 20:54:28 UTC 2023
Modified Files:
src/tests/usr.bin/xlint/lint1: msg_135.c
src/usr.bin/xlint/lint1: tree.c
Log Message:
lint: allow cast from a type to a union containing that type
To generate a diff of this commit:
cvs rdiff -u -r1.13 -r1.14 src/tests/usr.bin/xlint/lint1/msg_135.c
cvs rdiff -u -r1.518 -r1.519 src/usr.bin/xlint/lint1/tree.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/tests/usr.bin/xlint/lint1/msg_135.c
diff -u src/tests/usr.bin/xlint/lint1/msg_135.c:1.13 src/tests/usr.bin/xlint/lint1/msg_135.c:1.14
--- src/tests/usr.bin/xlint/lint1/msg_135.c:1.13 Sat Apr 22 19:45:04 2023
+++ src/tests/usr.bin/xlint/lint1/msg_135.c Sat Apr 22 20:54:28 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: msg_135.c,v 1.13 2023/04/22 19:45:04 rillig Exp $ */
+/* $NetBSD: msg_135.c,v 1.14 2023/04/22 20:54:28 rillig Exp $ */
# 3 "msg_135.c"
// Test for message: converting '%s' to '%s' increases alignment from %u to %u [135]
@@ -95,8 +95,6 @@ cast_to_union(void)
double p_align_8;
} *both;
- /* TODO: don't warn here. */
- /* expect+1: warning: converting 'pointer to int' to 'pointer to union both' increases alignment from 4 to 8 [135] */
both = (union both *)&align_4;
both = (union both *)&align_8;
return both->p_align_8;
Index: src/usr.bin/xlint/lint1/tree.c
diff -u src/usr.bin/xlint/lint1/tree.c:1.518 src/usr.bin/xlint/lint1/tree.c:1.519
--- src/usr.bin/xlint/lint1/tree.c:1.518 Sat Apr 22 20:17:19 2023
+++ src/usr.bin/xlint/lint1/tree.c Sat Apr 22 20:54:28 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: tree.c,v 1.518 2023/04/22 20:17:19 rillig Exp $ */
+/* $NetBSD: tree.c,v 1.519 2023/04/22 20:54:28 rillig Exp $ */
/*
* Copyright (c) 1994, 1995 Jochen Pohl
@@ -37,7 +37,7 @@
#include <sys/cdefs.h>
#if defined(__RCSID)
-__RCSID("$NetBSD: tree.c,v 1.518 2023/04/22 20:17:19 rillig Exp $");
+__RCSID("$NetBSD: tree.c,v 1.519 2023/04/22 20:54:28 rillig Exp $");
#endif
#include <float.h>
@@ -3451,6 +3451,17 @@ is_byte_array(const type_t *tp)
}
static bool
+union_contains(const type_t *utp, const type_t *mtp)
+{
+ for (const sym_t *mem = utp->t_sou->sou_first_member;
+ mem != NULL; mem = mem->s_next) {
+ if (types_compatible(mem->s_type, mtp, true, false, NULL))
+ return true;
+ }
+ return false;
+}
+
+static bool
should_warn_about_pointer_cast(const type_t *nstp, tspec_t nst,
const type_t *ostp, tspec_t ost)
{
@@ -3494,12 +3505,8 @@ should_warn_about_pointer_cast(const typ
if (nst == UNION || ost == UNION) {
const type_t *union_tp = nst == UNION ? nstp : ostp;
const type_t *other_tp = nst == UNION ? ostp : nstp;
- for (const sym_t *mem = union_tp->t_sou->sou_first_member;
- mem != NULL; mem = mem->s_next) {
- if (types_compatible(mem->s_type, other_tp,
- true, false, NULL))
- return false;
- }
+ if (union_contains(union_tp, other_tp))
+ return false;
}
if (is_struct_or_union(nst) && nstp->t_sou != ostp->t_sou)
@@ -3539,7 +3546,8 @@ convert_pointer_from_pointer(type_t *ntp
if (hflag && alignment_in_bits(nstp) > alignment_in_bits(ostp) &&
ost != CHAR && ost != UCHAR &&
- !is_incomplete(ostp)) {
+ !is_incomplete(ostp) &&
+ !(nst == UNION && union_contains(nstp, ostp))) {
/* converting '%s' to '%s' increases alignment ... */
warning(135, type_name(otp), type_name(ntp),
alignment_in_bits(ostp) / CHAR_SIZE,
