This is the mail archive of the gcc@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [RFC] PR/24900: computed but not used cast values


Aldy Hernandez <aldyh@redhat.com> writes:

> this reduces to:
> 
> 	int f(void);
> 	void g(void)
> 	{ (unsigned) f(); }
> 
> Which was made to deliberately warn by Joseph's patch here:
> 
> 	http://gcc.gnu.org/ml/gcc-patches/2005-08/msg00275.html
> 
> I closed the bug as a WONTFIX, but Ian suggested I bring this up on the
> list, as he believes the choice to warn on this, isn't a good one.

Basically, I don't think it helps anybody to issue a "value computed
is not used" warning for:
    (unsigned) f();

We traditionally do not warn about not using the value returned by a
function.  And I don't see why adding a cast should change that.
Intuitively, a cast by itself is not a computation.

Ian


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]