On Thu, May 19, 2022 at 01:10:42PM +0100, Quentin Monnet wrote: > 2022-05-19 09:21 UTC+0100 ~ Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx> > > Hi, > > > > On Wed, May 18, 2022 at 10:51:44PM +0800, Shung-Hsi Yu wrote: > >> On Thu, May 12, 2022 at 06:12:36PM -0700, Vincent Li wrote: > >>> On Thu, May 12, 2022 at 5:49 PM Vincent Li <vincent.mc.li@xxxxxxxxx> wrote: > >>>> > >>>> Hi, > >>>> > >>>> I cloned the bpf-next and tried to compile the bpf selftest. > >>>> > >>>> first I got error > >>>> > >>>> " > >>>> CC /usr/src/bpf > >>>> next/tools/testing/selftests/bpf/tools/build/bpftool/xlated_dumper.o > >>>> > >>>> make[1]: *** No rule to make target > >>>> '/usr/src/bpf-next/tools/include/asm-generic/bitops/find.h', needed by > >>>> '/usr/src/bpf-next/tools/testing/selftests/bpf/tools/build/bpftool/btf_dumper.o'. > >>>> Stop. > >> > >> I also ran into the same issue on bpf-next, and the error seems rather > >> absurd as > >> > >> 1. asm-generic/bitops/find.h was removed back in 47d8c15615c0a "include: > >> move find.h from asm_generic to linux", so perhaps this error has > >> something to do with Makefile.asm-generic > >> 2. normal way of building bpftool with `make tools/bpf/bpftool` still > >> works fine > >> > >> Anyway removing ARCH= CROSS_COMPILE= in the bpf selftests Makefile > >> (reverting change added in ea79020a2d9e "selftests/bpf: Enable > >> cross-building with clang") can be used as a workaround to get the build > >> working again. Adding the commit author to the thread to see if there is > >> better approach available. > > > > Could you share the commands that lead to this error? And did you make > > sure to clean the build tree? I often get errors when building tools > > because my toolchains changed and some dependencies in generated .*.d > > files do not exist anymore. In hindsight I likely did a clean after removing the cross-compile environment variables, and that's probably what made the build work, not the removal of ARCH= CROSS_COMPILE=. Sorry for jumping to conclusion. > > I can't reproduce this specific error on today's linux-next (but found > > another issue with out-of-tree build that I'll investigate). This is what > > I run, on an x86 host for an x86 target: > > > > $ make defconfig > > $ cat tools/testing/selftests/bpf/config >> .config > > # and enable CONFIG_DEBUG_INFO_BTF > > $ make > > $ make -C tools/testing/selftests TARGETS=bpf SKIP_TARGETS= > > > > Thanks, > > Jean > > Hi, for what it's worth I also observed the same today in samples/bpf; > but after "make clean" the issue disappeared, and I can't reproduce it > anymore. > > Quentin I also can't get the error to reproduce. Thanks, Shung-Hsi
