Re: [PATCH] KVM: 'asm' operand has impossible constraints

D. Hazelton
2007-01-27T21:46:18Z

On Saturday 27 January 2007 16:28, S.Çağlar Onur wrote:
> 27 Oca 2007 Cts tarihinde, Avi Kivity şunları yazmıştı:
> > The patch looks correct, but I don't understand the gcc error message.
> > Are we sure this isn't a gcc 4.2 bug?
> >
> > "g" appears to be equivalent to "rmi", if "i" is impossible, gcc is free
> > to use "r" or "m", no?
>
> Accorgind to GCC devs. its not a bug
> (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29808), on comment #5 the
> problem described like;
>
> "g" means "r"+"i" so the register allocator in the -O0 case is selecting
> "r" while in the optimize case is selecting "i"

Sounds like a bug to me! After all, shouldn't the different sections of code
be selecting the *same* bits ?

DRH