https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119514
Bug ID: 119514
Summary: Incorrect warning: 'I' flag used with '%f' gnu_scanf
format [-Wformat=]
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Keywords: diagnostic, false-positive
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: macro at orcam dot me.uk
Target Milestone: ---
Given this program:
$ cat bz13988.c
#include <stdio.h>
int
main (void)
{
double d;
scanf ("%Ilf", &d);
return 0;
}
$
I get this warning:
$ gcc -Wall -O2 -o bz13988 bz13988.c
bz13988.c: In function 'main':
bz13988.c:7:14: warning: 'I' flag used with '%f' gnu_scanf format [-Wformat=]
7 | scanf ("%Ilf", &d);
| ^
$
which according to Joseph Myers[1] has been incorrect since support for
the 'I' scanf flag was added for real formats back in 2007.
References:
[1] "stdio-common: Also reject exp char w/o significand in i18n scanf
[BZ #13988]",
<https://inbox.sourceware.org/libc-alpha/[email protected]/>
