[src/trunk]: src/tests/usr.bin/xlint/lint1 tests/lint: demonstrate warning fo...

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

details:   https://anonhg.NetBSD.org/src/rev/c1d812f786f5
branches:  trunk
changeset: 368115:c1d812f786f5
user:      rillig <rillig%NetBSD.org@localhost>
date:      Fri Jun 24 20:32:12 2022 +0000

description:
tests/lint: demonstrate warning for cast between compatible structs

diffstat:

 tests/usr.bin/xlint/lint1/msg_247.c |  39 ++++++++++++++++++++++++++++++++++--
 1 files changed, 36 insertions(+), 3 deletions(-)

diffs (71 lines):

diff -r 523cb49ccbbd -r c1d812f786f5 tests/usr.bin/xlint/lint1/msg_247.c
--- a/tests/usr.bin/xlint/lint1/msg_247.c       Fri Jun 24 20:16:21 2022 +0000
+++ b/tests/usr.bin/xlint/lint1/msg_247.c       Fri Jun 24 20:32:12 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: msg_247.c,v 1.22 2022/06/24 20:16:21 rillig Exp $      */
+/*     $NetBSD: msg_247.c,v 1.23 2022/06/24 20:32:12 rillig Exp $      */
 # 3 "msg_247.c"
 
 // Test for message: pointer cast from '%s' to '%s' may be troublesome [247]
@@ -103,7 +103,7 @@
 void *allocate(void);
 
 struct counter *
-counter_new(void)
+counter_new_typesafe(void)
 {
        struct counter_impl *impl = allocate();
        impl->public_part.count = 12345;
@@ -111,6 +111,16 @@
        return &impl->public_part;
 }
 
+struct counter *
+counter_new_cast(void)
+{
+       struct counter_impl *impl = allocate();
+       impl->public_part.count = 12345;
+       impl->saved_count = 12346;
+       /* expect+1: warning: pointer cast from 'pointer to struct counter_impl' to 'pointer to struct counter' may be troublesome [247] */
+       return (struct counter *)impl;
+}
+
 void
 counter_increment(struct counter *counter)
 {
@@ -156,7 +166,7 @@
         */
        return (struct lhash_st_OPENSSL_STRING *)OPENSSL_LH_new();
 }
-# 160 "msg_247.c" 2
+# 170 "msg_247.c" 2
 
 void sink(const void *);
 
@@ -272,3 +282,26 @@
 
        return t6;
 }
+
+
+// From jemalloc.
+
+typedef struct ctl_node_s {
+       _Bool named;
+} ctl_node_t;
+
+typedef struct ctl_named_node_s {
+       ctl_node_t node;
+       const char *name;
+} ctl_named_node_t;
+
+void *
+cast_between_initial_struct(void *ptr)
+{
+       /* expect+1: warning: pointer cast from 'pointer to struct ctl_named_node_s' to 'pointer to struct ctl_node_s' may be troublesome [247] */
+       void *t1 = (ctl_node_t *)(ctl_named_node_t *)ptr;
+
+       void *t2 = (ctl_named_node_t *)(ctl_node_t *)ptr;
+
+       return t2;
+}