[PATCH 0/3] Make glibc build with LLD

[H.J. Lu]

On Thu, Jan 7, 2021 at 9:05 PM Fāng-ruì Sòng via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>
> On Mon, Dec 28, 2020 at 11:48 AM Fangrui Song <maskray@google.com> wrote:
> >
> > I sent the first two in April. Resending in a patch series to be
> > clearer.
> >
> >   install: Replace scripts/output-format.sed with objdump -f
> >
> > replaced https://sourceware.org/pipermail/libc-alpha/2020-April/112733.html
> > by leveraging objdump -f.
> >
> > With this patch series (available in https://sourceware.org/git/?p=glibc.git;a=shortlog;h=refs/heads/maskray/lld),
> > `make` with ld pointing to ld.lld (LLVM linker) works.
> >
> > Fangrui Song (3):
> >   configure: Allow LD to be a linker other than GNU ld and gold
> >   elf: Replace a --defsym trick with an object file to be compatible
> >     with lld
> >   install: Replace scripts/output-format.sed with objdump -f
> >
> >  Makerules                                     | 13 ++-----
> >  .../strcoll-inputs/filelist#en_US.UTF-8       |  1 -
> >  config.make.in                                |  1 -
> >  configure                                     | 32 +++++------------
> >  configure.ac                                  | 24 +++++--------
> >  elf/Makefile                                  | 11 +++---
> >  scripts/output-format.sed                     | 35 -------------------
> >  7 files changed, 23 insertions(+), 94 deletions(-)
> >  delete mode 100644 scripts/output-format.sed
> >
> > --
> > 2.29.2.729.g45daf8777d-goog
> >
>
> Hope "elf:" and "install:" can be reviewed (they are nice
> simplification on their own), even if you don't want to take
> "configure:" for now.
>
> For __rela_iplt_start, I gave a fair assessment on
> https://bugs.llvm.org/show_bug.cgi?id=48674#c4 . I feel bad that an
> improvable binutils issue caused the block of a static-pie relocation
> improvement

No.  There is no need to work around the lld bug which can be fixed.

> "Make _dl_relocate_static_pie return an int indicating whether it
> applied relocs." The other few failures (e.g. not supporting ld.lld
> --audit / tls common) are not really usability affecting issues.

"make check" should be clean.  Otherwise, we have no way to
know if glibc is built properly on x86.

-- 
H.J.