Re: [PATCH] conf, tap: Silence two false positive invalidFunctionArg from cppcheck

[Stefano Brivio <sbrivio@redhat.com>]

On Fri, 17 Feb 2023 09:29:51 -0500
Laine Stump <laine@redhat.com> wrote:

> On 2/16/23 5:53 PM, David Gibson wrote:
> > On Thu, Feb 16, 2023 at 07:22:10PM +0100, Stefano Brivio wrote:  
> >> The newly introduced die() calls exit(), but cppcheck doesn't see it
> >> and warns about possibly invalid arguments used after the check which
> >> triggers die(). Add return statements to silence the warnings.
> >>
> >> Signed-off-by: Stefano Brivio <sbrivio@redhat.com>  
> > 
> > Oof, that's super ugly.  Any chance that cppcheck will recognize the
> > ((noreturn)) attribute if we added it to die()?  
> 
> Why is this only a problem in these two files?

Because that's where we would use a variable as a system call argument,
if the check possibly leading to die() didn't exist.

> (and is there a "make check" target that I should have been running and 
> haven't?)

make cppcheck, make clang-tidy, and possibly the tests (see
test/README.md) -- but it's not mandatory, especially if you're an
occasional contributor, I'm running them anyway.

> Requiring an extra "return" after die() kind of removes the advantage of 
> using it over err(). :-/ If we have to do that, it would be more 
> straightforward to just use err() followed by exit() directly.

We don't have to (see the rest of this thread): we could simply define
die() as err() with an additional return statement *outside* err()
itself, instead of passing 'doexit' as parameter. Probably something
like:

do {
	err(...)
	exit(EXIT_FAILURE);
	return;
} while (0)

-- 
Stefano