Re: [Qemu-devel] [PATCH v3] avoid compilation warning/errors on up to date compilers/glibc

[Jean-Christophe Dubois]

Le mercredi 17 juin 2009 16:03:51, vous avez écrit :
> > > This is no more correct than before.  read() can return EINTR and that
> > > should be handled appropriately.  Elsewhere, read() can return partial
> > > results and we ought to handle that properly.
> >
> > It handles all cases except EINTR. And in the actual code base EINTR and
> > __all other__ error cases are not handled. So as of today EINTR is not
> > handled propely (as well as all other error cases). So this consider
> > EINTR as an error when it could be handled in a nicer way. Previously no
> > ERRORS were considered as an error. What is best?
>
> The original is the lesser wevil because it is obviously wrong. Your patch
> looks like it does error handling and avoids generates warnings, but still
> does not work correctty.
>
> > > Using -D_FORTIFY_SOURCES=0 will eliminate these warnings.  If we're
> > > going to fix these things, we should fix them properly.
> >
> > It just hides the problem and fix nothing but the compilation.
>
> Your patch just makes the bug more subtle and harder to spot.

I guess this is a matter of point of view. 

Is it harder to find a bug when:
1) you are silencing compilation warning/errors AND ignoring all runtime 
errors (also silencing future warnings/errors).
or 2) You are considering recoverable errors as non recoverable errors.

You make your call.

Anyway fixing all those "bad" calls the "proper" way will be quite involved.

BTW are you sure that EINTR and EAGAIN are correctly handled all over the 
source code? What about partial read/write?

JC


>
> Paul