Re: Fedora's latest gcc produces unbootable kernels

From: Bill Davidsen
Date: Sat Dec 01 2007 - 13:22:25 EST


Pierre Ossman wrote:
On Sat, 1 Dec 2007 15:42:23 +0100
Pierre Ossman <drzeus-list@xxxxxxxxx> wrote:

The latest GCC in Fedora rawhide contains some serious bug (or provokes a latent one in the kernel) that makes every kernel built unbootable. It just locks up halfway through the init. Kernels that previously worked fine all now experience the same symptom. Even RH's own kernels exhibit this. The kernel built Nov 24th works, Nov 26th doesn't. gcc was updated 26th, 14 hours earlier.


Digging a bit further, it is indeed the high-res stuff (the first missing message) that hangs. If I hard code the kernel to just be non-high-res capable, it boots, but time keeping is horribly broken.

Anyway, hopefully this means I'll soon have the object file that gets miscompiled. Jakub also pointed me to an older gcc RPM so that I can produce an object file with that as well and see what differs.

If you are referring to the "compat" RPMs, be aware that they use the current headers, which is a good or bad thing depending on what you want to do. If you want to build old software, you get to keep a down-rev virtual machine to do it right :-(

--
Bill Davidsen <davidsen@xxxxxxx>
"We have more to fear from the bungling of the incompetent than from
the machinations of the wicked." - from Slashdot
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