[Bug c/101358] Warn when saving a pointer to an object with temporary lifetime
msebor at gcc dot gnu.org
gcc-bugzilla@gcc.gnu.org
Wed Jul 7 21:59:40 GMT 2021
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101358
Martin Sebor <msebor at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Blocks| |87403
CC| |msebor at gcc dot gnu.org
Ever confirmed|0 |1
Last reconfirmed| |2021-07-07
Severity|normal |enhancement
--- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> ---
Confirmed as an enhancement request for the front end. The Gimplifier
introduces a local variable for the return value so the problem is no longer
detectable:
$ cat pr101358.c && /build/gcc-master/gcc/xgcc -B /build/gcc-master/gcc -S
-Wall -fdump-tree-original=/dev/stdout -fdump-tree-gimple=/dev/stdout
pr101358.c
typedef struct {
int x[1];
} foo;
foo f(void);
int g(void) {
int *p = f().x;
return *p;
}
;; Function g (null)
;; enabled by -tree-original
{
int * p = (int *) &f ().x;
int * p = (int *) &f ().x;
return *p;
}
int g ()
{
struct
{
int x[1];
} D.1952;
int D.1953;
int * p;
D.1952 = f ();
p = &D.1952.x;
D.1953 = *p;
return D.1953;
}
Referenced Bugs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87403
[Bug 87403] [Meta-bug] Issues that suggest a new warning
More information about the Gcc-bugs
mailing list