Re: request for enhancement in BFD and gold linkers in regards to .comment section

[Nick Clifton <nickc@redhat.com>]

Hi Tom,

> I have noticed that the LLVM linker will add something to the .comment
> section of binaries it produces for the version of lld used to produce an
> ELF executable or shared library.

Does it ?  I do not see this:

    % clang hello.c
    % readelf -p.comment a.out

   String dump of section '.comment':
     [     0]  GCC: (GNU) 12.2.1 20221121 (Red Hat 12.2.1-4)
     [    2e]  GCC: (GNU) 12.0.1 20220413 (Red Hat 12.0.1-0)
     [    5c]  clang version 14.0.5 (Fedora 14.0.5-2.fc36)

So there is a note for the version of Clang, but not one for the version of lld.
Maybe this is a new feature ?  I am using  clang/llvm/lld version 14.0.5.


> For the gold liker, I see I can do a readelf -p .note.gnu.gold-version and
> get the version of gold used to make an ELF file.

Again I do not see this:

   % gcc hello.c -fuse-ld=gold
   % readelf -p.comment a.out

   String dump of section '.comment':
     [     1]  GCC: (GNU) 12.2.1 20221121 (Red Hat 12.2.1-4)
     [    2f]  GCC: (GNU) 12.0.1 20220413 (Red Hat 12.0.1-0)


>  I see nothing similar for the BFD linker.

True - this feature is not currently supported.


> So the request for enhancement is to add something to the .comment section
> as to which version of the BFD or gold linker was used to produce the ELF.
> 
> I can file a BZ if that is the preferred way of receiving a request such as
> this.

It is, so please do file a BZ.  If you can include a reproducer that would help.

Cheers
   Nick