On Fri, Jan 17, 2020 at 7:30 AM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote: > > On Wed, Jan 15, 2020 at 3:53 AM Ilie Halip <ilie.halip@xxxxxxxxx> wrote: > > > > The semantics of `--undefined` differ between ld.bfd and ld.lld: > > $ echo | gcc -x c -c - -o a.o > > $ echo "EXTERN(test)" > a.lds > > $ ld.bfd a.o -t a.lds -o - 2>/dev/null && objdump -t | grep test > > 0000000000000000 *UND* 0000000000000000 test > > $ ld.lld a.o -t a.lds -o - 2>/dev/null && objdump -t | grep test > > $ > > > > When building with CONFIG_STM=m, there are no in-kernel users of memcat_p() > > and ld.lld discards this symbol because it's linked in via --no-whole-archive. > > It's marked as undefined by a linker script but ld.lld discards it anyway (as > > seen in the above snippet). > > > > Work around the ld.lld behavior by moving the object file to obj-y. > > > > Signed-off-by: Ilie Halip <ilie.halip@xxxxxxxxx> > > Link: https://github.com/ClangBuiltLinux/linux/issues/515 > > Thanks for the patch. This solves the observed linkage failure. > Maybe Masahiro has more input based on the discussion in the above > Link? Sorry, I did not notice that thread until now. I will take a look at it when I have time. This patch does not seem to be a proper fix. If this fix-up were acceptable, theoretically, all objects that contain EXPORTED_SYMBOL would need to be turned into obj-y from lib-y ? > Tested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> -- Best Regards Masahiro Yamada
