Re: mutex failing (stupid C++!)

4 msg	problem building gcc-4.3 snapshot in home dir

mutex failing (stupid C++!)
\ skaller (31 Oct 2007)
. \ Ian Lance Taylor (31 Oct 2007)
. \ Kaz Kylheku (31 Oct 2007)
. . \ Miles Bader (31 Oct 2007)
. . . \ skaller (1 Nov 2007)

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Subject:	Re: mutex failing (stupid C++!)
Group:	Gcc-help
From:	Miles Bader
Date:	31 Oct 2007

"Kaz Kylheku" <kaz> writes:
> This should be diagnosed by -Wunused, IMHO. You are calling a
> constructor, but ignoring the return value.
...
> into the program, -Wunused will give you a diagnostic. But if you
> construct an object and ignore the result, you don't get a diagnostic.

Of course constructors (and destructors) can have side-effects, and it's
not that uncommon to create objects just for such side-effects. I'm not
sure how common it is to use _unnamed_ objects in this way (I've never
done it I think, and it seems ever so slightly dodgy), but obviously it's
possible...

I guess gcc could warn when there are obviously no side-effects but who
knows how easy that is (and maybe the few cases it catches aren't worth
the effort).

-Miles
--
"Suppose He doesn't give a shit? Suppose there is a God but He
just doesn't give a shit?" [George Carlin]