https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91809
Bug ID: 91809
Summary: in c++ bit-field is not promoted to int in printf
argument
Product: gcc
Version: 10.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: nsz at gcc dot gnu.org
Target Milestone: ---
may be a -Wformat bug only, but the c++ front-end seems
to use the wrong type:
#include <stdio.h>
struct X {
unsigned long long a: 1;
} x;
void foo()
{
printf("%d", x.a);
}
gcc -Wformat -xc++ says
a.c: In function 'void foo()':
a.c:9:12: warning: format '%d' expects argument of type 'int', but argument 2
has type 'long long unsigned int' [-Wformat=]
9 | printf("%d", x.a);
| ~^ ~~~
| | |
| int long long unsigned int
| %lld
the warning is not present with -xc, which is
the expected behaviour: bit-field should be
promoted to int in this context, i don't think
c++ should behave differently.
(not a new regression, at least present since gcc-4.8)
