On Tue, Jul 30, 2024, at 05:59, Linus Torvalds wrote: > On Mon, 29 Jul 2024 at 16:21, Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxx> wrote: >> >> Attached is the patch I have in my tree right now - it complains about >> a 'bcachefs' comparison between an 'u16' and a 's64', because I also >> removed the 'implicit integer promotion is ok' logic, because I think >> it's wrong. I'm giving this a spin on the randconfig test setup now to see if there are some other cases like the bcachefs one. So far I've seen one failure, but I can't make sense of it yet: drivers/gpu/drm/i915/display/intel_backlight.c: In function 'scale': include/linux/compiler_types.h:510:45: error: call to '__compiletime_assert_905' declared with attribute error: clamp() low limit source_min greater than high limit source_max include/linux/minmax.h:107:9: note: in expansion of macro 'BUILD_BUG_ON_MSG' 107 | BUILD_BUG_ON_MSG(statically_true(ulo > uhi), \ drivers/gpu/drm/i915/display/intel_backlight.c:47:22: note: in expansion of macro 'clamp' 47 | source_val = clamp(source_val, source_min, source_max); See https://pastebin.com/raw/yLJ5ZqVw for the x86-64 .config that triggered this. >> I don't think a min(u16,s64) is a valid minimum, for exactly the same >> reason a min(u32,s64) is not valid. > > Oh, and I noticed that it screws up the 32-bit case, and that does > need a workaround for that. > > So here's a better version. The patch contains one possible fix to > bcachefs for the type confusion there, but I'll wait for Kent to > respond on that. That's still a typo in the 32-bit case, right? I've changed __builtin_choose_expr(sizeof(ux)>32,1LL,1L)) to check for sizeof(ux)>4 for my testing. Arnd
