Re: Fedora's latest gcc produces unbootable kernels

[Thomas Gleixner]

On Mon, 3 Dec 2007, Jakub Jelinek wrote:

> On Mon, Dec 03, 2007 at 12:34:17PM +0100, Thomas Gleixner wrote:
> > Of course just to annoy you :)
> 
> It doesn't matter whether I'm annoyed about this or not, but whether gcc is
> able to generate decent code with it or not.  And especially with union it
> is not, at least through all the tree ssa passes.  You already have a lot of
> the details hidden in ktime.h accessor inlines, so I don't think it would be
> hard to add further one or two.
> 
> Anyway, even just using typedef struct ktime { s64 tv64; } ktime_t; could
> make things better in case you have just one field.  Unlike unions, structs
> can be (and in this case most likely will be) scalarized by SRA, so
> half of tree SSA passes will see it as integral var and will be able to
> perform optimizations on it.

Makes sense. I look into fixing that.

Thanks,

	tglx
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