On 6/7/21 5:49 PM, Hyeonggon Yoo wrote: > On Mon, Jun 07, 2021 at 05:27:27PM +0200, Vlastimil Babka wrote: >> On 6/7/21 2:25 PM, Hyeonggon Yoo wrote: >> > On Mon, Jun 07, 2021 at 01:40:02PM +0200, Vlastimil Babka wrote: >> >> On 6/6/21 1:08 PM, Hyeonggon Yoo wrote: >> >> > On Sat, Jun 05, 2021 at 02:10:46PM +0800, kernel test robot wrote: >> >> >> >> But what exactly is the gcc problem here? >> >> Did you have to reproduce it with specific gcc version and/or architecture? >> >> >> > >> > Before replying, I should say that I'm not an expert on gcc. >> > I just tried some ways to fix the error, and it seemed to me that >> > gcc is doing something wrong. >> >> I'm involving my gcc colleagues, will report results... Well, it seems the bot's .config included CONFIG_PROFILE_ALL_BRANCHES as the main factor to trigger the problem. And (according to my colleagues) it might add too many instrumented if conditions to sustain the builtin-constant tracking, which is not unlimited, or interact with optimizations in some other corner case way. I guess we could add IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) to the list of conditions that excludes using BUILD_BUG_ON_MSG(). > Thank you so much! > > Hyeonggon >
