On 04/06/2024 05:55, John Hubbard wrote: > On 6/3/24 3:47 PM, Nathan Chancellor wrote: >> On Mon, Jun 03, 2024 at 04:32:30PM +0100, Mark Brown wrote: >>> On Fri, May 31, 2024 at 11:37:50AM -0700, John Hubbard wrote: >>>> The kselftests may be built in a couple different ways: >>>> make LLVM=1 >>>> make CC=clang >>>> >>>> In order to handle both cases, set LLVM=1 if CC=clang. That way,the rest >>>> of lib.mk, and any Makefiles that include lib.mk, can base decisions >>>> solely on whether or not LLVM is set. >>> >>> ICBW but I believe there are still some architectures with clang but not >>> lld support where there's a use case for using CC=clang. >> >> Does CC=clang even work for the selftests? lib.mk here uses 'CC :=' so >> won't CC=clang get overridden to CC=$(CROSS_COMPILE)gcc? >> > > I received a report that someone (I forget who or what) was definitely > attempting to just set CC=clang. But yes, it definitely doesn't work > properly for CROSS_COMPILE. This history as I recall, is that I got a bug report [1] stating that: # tools/testing/selftests/fchmodat2$ make CC=clang and # tools/testing/selftests/openat2$ make CC=clang were both failing due to the -static-libsan / -static-libasan difference between gcc and clang. I attempted to fix that with [2], which used cc-option to determine which variant to use. That never got picked up, and John coincidentally did a similar fix, but relying on LLVM=1 instead. If we are concluding that CC=clang is an invalid way to do this, then I guess we should report that back to [1]? [1] https://lore.kernel.org/all/202404141807.LgsqXPY5-lkp@xxxxxxxxx/ [2] https://lore.kernel.org/linux-kselftest/20240417160740.2019530-1-ryan.roberts@xxxxxxx/ Thanks, Ryan > > And the more we talk it through, the less I like this direction that > I went off on. Let's just drop this patch and instead consider moving > kselftest builds closer to kbuild, instead of making it more different. > > > thanks,
