https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106854
Bug ID: 106854
Summary: [[gnu::malloc(deallocator)]] for non-pointer functions
(e.g., fd)
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: ---
Some stuff is allocated and deallocated through non-pointer types. Most of the
time it's file descriptors, i.e., int.
Since [[gnu::malloc(f)]] is independent of [[gnu::malloc]], it could be used
for such cases:
int close(int fd);
[[gnu::malloc(close)]]
int open(const char *pathname, int flags, ...);
Notice that [[gnu::malloc]] can't be used above.
[[gnu::malloc(f)]] has no reason to be restricted to functions returning
pointers, has it?
Could you allow using it for file descriptors? Otherwise, a more generic
[[open(close)]] attribute might be reasonable.
Currently, it results in a warning:
$ cat fd.c && echo && cc -Wall -Wextra -S fd.c
#include <fcntl.h>
#include <unistd.h>
[[gnu::malloc(close)]]
int g(void)
{
return open("foo", O_RDONLY);
}
fd.c:6:1: warning: ‘malloc’ attribute ignored on functions returning ‘int’;
valid only for pointer return types [-Wattributes]
6 | {
| ^
