https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106850
Bug ID: 106850
Summary: restrict type qualifier ignored on function return
type
Product: gcc
Version: 12.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: colomar.6.4.3 at gmail dot com
Target Milestone: ---
Related: <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87313>
The description of the restrict qualifier would lead one to think that it can
be used as a standard way of describing a function that returns a unique
pointer, as the [[gnu::malloc]] attribute does in GNU C.
GCC currently ignores the qualifier, so it can't use it for the optimizations
that [[gnu::malloc]] allows, but if GCC didn't ignore the qualifier, it could
be used for that.
```c
#include <err.h>
#include <stddef.h>
#include <stdlib.h>
#include <stdio.h>
[[gnu::malloc(free)]]
void *restrict
my_malloc(size_t size)
{
void *p;
p = malloc(size);
if (!p)
err(EXIT_FAILURE, "malloc(2)");
return p;
}
```
```sh
$ cc -Wall -Wextra my_malloc.c -S
my_malloc.c:8:1: warning: type qualifiers ignored on function return type
[-Wignored-qualifiers]
8 | my_malloc(size_t size)
| ^~~~~~~~~
```
Could you please not ignore the qualifier, and treat it as synonym of
[[gnu::malloc]]?
