https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97858
Martin Sebor <msebor at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Last reconfirmed|2020-11-17 00:00:00 |2021-4-9
Summary|Bogus warnings about |avoid mentioning va_list
|va_list |internal fields in
| |-Wuninitialized
CC| |msebor at gcc dot gnu.org
--- Comment #12 from Martin Sebor <msebor at gcc dot gnu.org> ---
(In reply to Jan Hubicka from comment #7)
> Thanks, my original intention was to mostly track the fact that we do not
> want
> to warn about fields of va_list type that is internal to compiler though
> :)
To be clear: for the following test case you suggest to issue just the one
warning below:
$ cat pr97858.c && gcc -O2 -S -Wall pr97858.c
void f (__builtin_va_list);
int g (int i, ...)
{
__builtin_va_list ap;
// __builtin_va_start (ap, i);
int x = __builtin_va_arg (ap, int);
__builtin_va_end (ap);
return x;
}
pr97858.c: In function ‘g’:
pr97858.c:8:7: warning: ‘ap’ is used uninitialized [-Wuninitialized]
8 | int x = __builtin_va_arg (ap, int);
| ^
pr97858.c:5:21: note: ‘ap’ declared here
5 | __builtin_va_list ap;
| ^~
as opposed to the three GCC issues now:
pr97858.c: In function ‘g’:
pr97858.c:8:7: warning: ‘ap[0].gp_offset’ is used uninitialized
[-Wuninitialized]
8 | int x = __builtin_va_arg (ap, int);
| ^
pr97858.c:5:21: note: ‘ap’ declared here
5 | __builtin_va_list ap;
| ^~
pr97858.c:8:7: warning: ‘ap[0].reg_save_area’ may be used uninitialized
[-Wmaybe-uninitialized]
8 | int x = __builtin_va_arg (ap, int);
| ^
pr97858.c:5:21: note: ‘ap’ declared here
5 | __builtin_va_list ap;
| ^~
pr97858.c:8:7: warning: ‘ap[0].overflow_arg_area’ may be used uninitialized
[-Wmaybe-uninitialized]
8 | int x = __builtin_va_arg (ap, int);
| ^
pr97858.c:5:21: note: ‘ap’ declared here
5 | __builtin_va_list ap;
| ^~
