Re: [PATCH] audit: avoid -Wempty-body warning
On Mon, Mar 22, 2021 at 6:58 PM Richard Guy Briggs <rgb(a)redhat.com> wrote:
On 2021-03-22 17:28, Arnd Bergmann wrote:
> On Mon, Mar 22, 2021 at 3:33 PM Richard Guy Briggs <rgb(a)redhat.com> wrote:
> > > Change the macros to use the usual "do { } while (0)" instead,
and change a
> > > few more that were (void)0, for consistency.
> >
> > So what about audit_put_watch() and audit_get_watch() which are set to
> > {}? (And all of include/linux/audit.h that uses the latter...) Does
> > this only matter if they are the only action called in an if or loop?
>
> I missed those, thanks for pointing it out. I sent a v2 patch now.
Ok, cool, that looks more consistent. Can you answer my question about
include/linux/audit.h and exactly what conditions require
"do { } while (0)" over "{ }"?
This is the usual way of constructing a C expression that can be used
e.g. in
if (x)
foo();
else
bar();
If foo() is defined as '{}', this causes a syntax error.
Arnd