Re: [bisected] clang 15 built kernel fails to boot, stuck at "Loading Linux 6.1.1 ...", gcc 12 built kernel with same config boots fine

From: Peter Zijlstra
Date: Fri Jan 20 2023 - 05:27:38 EST


On Fri, Jan 20, 2023 at 11:20:53AM +0530, Sandipan Das wrote:
> With the combination of defconfig+kvm_guest.config+localyesconfig, the only
> thing that made a difference was the compiler optimization choice. The kernel
> boots up with CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE=y but not with
> CONFIG_CC_OPTIMIZE_FOR_SIZE=y. Both Clang 15 and 16 kernel builds are affected.

-Os(tupid) strikes again :-)

Lemme go try that.