On Tue, Mar 01, 2022 at 10:24:48AM -0800, Andrew Morton wrote:
> > lib/vsprintf.c: In function 'va_format':
> > lib/vsprintf.c:1759:9: warning: function 'va_format' might be a candidate for 'gnu_printf' format attribute [-Wsuggest-attribute=format]
> > 1759 | buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va);
> > | ^~~
>
> I wonder what this means.
It means the compiler thinks we might want to add:
__attribute__((format(gnu_printf, x, y))) to the function declaration so it
can type-check the arguments.
'format (ARCHETYPE, STRING-INDEX, FIRST-TO-CHECK)'
The 'format' attribute specifies that a function takes 'printf',
'scanf', 'strftime' or 'strfmon' style arguments that should be
type-checked against a format string. For example, the
declaration:
extern int
my_printf (void *my_object, const char *my_format, ...)
__attribute__ ((format (printf, 2, 3)));
causes the compiler to check the arguments in calls to 'my_printf'
for consistency with the 'printf' style format string argument
'my_format'.
I haven't looked into this at all and have no idea if we should.
