Re: [PATCH] binutils: partially revert 17c6c3b99156fe82c1e637e1a5fd9f163ac788c8

["H.J. Lu" <hjl.tools@gmail.com>]

On Thu, Nov 17, 2022 at 9:44 AM 徐持恒 Xu Chiheng via Binutils
<binutils@sourceware.org> wrote:
>
> Phenomenal:  In 32 bit and 64 bit mixed code,  ld can't do relocation
> for 32 bit code.
> It is caused by commit 17c6c3b99156fe82c1e637e1a5fd9f163ac788c8.
>
>
>
>
>   /* src_mask selects the part of the instruction (or data) to be used
>      in the relocation sum.  If the target relocations don't have an
>      addend in the reloc, eg. ELF USE_REL, src_mask will normally equal
>      dst_mask to extract the addend from the section contents.  If
>      relocations do have an addend in the reloc, eg. ELF USE_RELA, this
>      field should normally be zero.  Non-zero values for ELF USE_RELA
>      targets should be viewed with suspicion as normally the value in
>      the dst_mask part of the section contents should be ignored.  */
>   bfd_vma src_mask;
>
>
>
> Author: Jan Beulich <jbeulich@suse.com>  2021-05-07 18:05:12
> Committer: Jan Beulich <jbeulich@suse.com>  2021-05-07 18:05:12
> Parent: 98da05bf2698b55b73453480a3fbb92f163d2c7b (x86: don't mix disp
> and imm processing)
> Child:  4cf88725da1cb503be04d3237354105ec170bc86 ([gdb/symtab] Fix
> infinite recursion in dwarf2_cu::get_builder())
> Branches: master, test0558-01 and many more (41)
> Follows: gdb-10-branchpoint
> Precedes: binutils-2_37, gdb-11-branchpoint
>
>     x86-64/ELF: clear src_mask for all reloc types
>
>     x86-64 uses rela relocations. The comment next to the field's declaration
>     says "Non-zero values for ELF USE_RELA targets should be viewed with
>     suspicion ..." And indeed the fields being non-zero causes section
>     contents to be accumulated into the final relocated values in addition to
>     the relocations' addends, which is contrary to the ELF spec.

Are you using NASM?

-- 
H.J.