Bad gcc-4.1.0 leads to Power4 crashes... and power5 too, actually

[Linas Vepstas]

On Tue, Dec 19, 2006 at 07:46:50PM -0600, Peter Bergner wrote:
> On Tue, 2006-12-19 at 18:46 -0600, Linas Vepstas wrote:
> > Per xchat, here's the update. I'm guessing I'm using a broken
> > compiler, as per chain of evidence below ...
> [snip]
> > However, I also note that the following scrolled by:
> > init/main.c:81:2: warning: #warning gcc-4.1.0 is known to miscompile the
> > kernel. A different compiler version is recommended.
> 
> It may be due to this GCC bug which Olaf ran into a while back:
> 
>   http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24644
> 
> You can verify whether you have a broken compiler by compiling
> the minimal test case I posted in comment #15.  If you see r13
> being copied into another register and then used, then you have
> a broken compiler.

No, that's not it. I'd be surprised, as I was using the SuSE
SLES10 gcc-4.1.0-28.4.ppc.rpm compiler, which would have that fix.

I'm trying to figure out how to try a different compiler,
I'm hoping that 3.3 can still compile new kernels.

I'll try to stare at the dump a bit too, now.

--linas