https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110091
Bug ID: 110091
Summary: bogus -Wdangling-pointer on non-pointer values
Product: gcc
Version: 12.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: patrickdepinguin at gmail dot com
Target Milestone: ---
Following reduced testcase gives a bogus -Wdangling-pointer:
struct tEntry
{
int value;
};
struct tOut
{
int outvalue;
};
extern struct tOut *out;
extern int otherfunc(struct tEntry *);
extern void anotherfunc(int val);
void bar()
{
struct tEntry entry = { 0 };
if (otherfunc(&entry) != 0)
{
return;
}
if (out)
{
out->outvalue = entry.value;
}
anotherfunc(5);
}
void foo()
{
bar();
}
$ gcc -O2 -Wall -Werror /opt/test.c
/opt/test.c: In function 'bar':
/opt/test.c:26:30: error: dangling pointer to 'entry' may be used
[-Werror=dangling-pointer=]
26 | out->outvalue = entry.value;
| ~~~~~^~~~~~
/opt/test.c:17:19: note: 'entry' declared here
17 | struct tEntry entry = { 0 };
| ^~~~~
In function 'bar',
inlined from 'foo' at /opt/test.c:34:5:
/opt/test.c:26:30: error: dangling pointer to 'entry' may be used
[-Werror=dangling-pointer=]
26 | out->outvalue = entry.value;
| ~~~~~^~~~~~
/opt/test.c: In function 'foo':
/opt/test.c:17:19: note: 'entry' declared here
17 | struct tEntry entry = { 0 };
| ^~~~~
cc1: all warnings being treated as errors
entry is a local struct, initialized to 0, and passed as pointer to an external
function.
But the use being warned about is not using any pointer.
Tested with 12.2.0 (Debian), 12.2.1 (Gentoo), 12.3.0 (official gcc docker
image), 13.1.0 (official gcc docker image).
