Re: crosstool: x86 kernel compiled with GCC 14.1 fails to boot

[Arnd Bergmann]

On Mon, Jul 8, 2024, at 20:16, Kalle Valo wrote:
> Hi Arnd,
>
> I installed GCC 14.1 from:
>
> https://mirrors.edge.kernel.org/pub/tools/crosstool/files/bin/x86_64/14.1.0/
>
> But I have a problem that a kernel compiled with that compiler fails to
> boot on my x86 NUC test box. I don't see any errors, just black screen
> and I assume after that the kernel either crashes or reboots and goes to
> back to the GRUB menu. This loop seems to continue forever. GCC 13.2 and
> older from crosstool work just fine.
>
> Do you happen to have any ideas what could cause this or how to debug
> further?

Thanks for the report. Unfortunately I have no idea what the
problem may be, and so far nobody else has reported this.

For debugging, what I'd try first is to run the same kernel in
qemu to see if that works, or attach gdb and step through the
early boot if it doesn't.

I have tried reproducing it, but with my arm64 hosted x86-64
cross-compiler, it boots a defconfig x86-64 kernel in qemu just
fine.

     Arnd