On Tue, Sep 14, 2021 at 11:05 PM Harry Wentland <harry.wentland@xxxxxxx> wrote: > > [Why & How] > With Werror enabled in the kernel we were failing the clang build since > dml21_ModeSupportAndSystemConfigurationFull's stack frame is 1064 when > building with clang, and exceeding the default 1024 stack frame limit. > > The culprit seems to be the Pipe struct, so pull the relevant block > out into its own sub-function. I suspect it's not the Pipe struct but rather the way that you call another function with a crazy number of arguments here. After your change, this likely gets inlined and you avoid the problem, so the patch ends up doing the right thing. If you do more patches like this, I would suggest mentioning the new stack usage of the calling function and the new noinline function, to make sure that the combined number isn't actually worse than the old number. You can get these numbers by recompiling the file with the frame size warning set to a low value, e.g. adding -Wframe-larger-than=100 to the command line. Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
