[syslinux] [PATCH 0/4] Improve linker scripts

[Gene Cumm]

On Thu, Oct 8, 2015 at 7:24 PM, Celelibi <celelibi at gmail.com> wrote:
> 2015-10-08 12:58 UTC+02:00, Gene Cumm <gene.cumm at gmail.com>:
>> On Mon, Oct 5, 2015 at 2:15 PM, celelibi--- via Syslinux
>> <syslinux at zytor.com> wrote:
>>> From: Sylvain Gault <sylvain.gault at gmail.com>
>>>
>>> These patches basically remove unused linker scripts and port a change
>>> that was
>>> made to an unused script.
>>>
>>> Those are to be applied on top of the gcc 5 bug fixes as they would
>>> conflict
>>> otherwise.
>>>
>>> Sylvain Gault (4):
>>>   diag/mbr: fix dependency to linker script
>>>   Remove unused linker scripts
>>>   core: Make symbols defined in linker script HIDDEN
>>>   core: Move linker script in arch-agnostic dir
>>>
>>>  core/Makefile           |   2 +-
>>>  core/i386/syslinux.ld   | 389
>>> ------------------------------------------------
>>>  core/syslinux.ld        | 117 ++++++---------
>>>  core/x86_64/syslinux.ld | 389
>>> ------------------------------------------------
>>>  diag/mbr/Makefile       |   2 +-
>>>  efi/syslinux.ld         | 176 ----------------------
>>>  mbr/mbr.ld              |  73 ---------
>>>  memdisk/memdisk.ld      | 140 -----------------
>>>  8 files changed, 48 insertions(+), 1240 deletions(-)
>>>  delete mode 100644 core/i386/syslinux.ld
>>>  delete mode 100644 core/x86_64/syslinux.ld
>>>  delete mode 100644 efi/syslinux.ld
>>>  delete mode 100644 mbr/mbr.ld
>>>  delete mode 100644 memdisk/memdisk.ld
>>
>>
>> gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5)
>> GNU ld (GNU Binutils for Ubuntu) 2.22
>>
>>
>> ld -m elf_i386  -Bsymbolic -pie -E --hash-style=gnu -T
>> /home/gene/s/g/core/syslinux.ld -M -o ldlinux.elf ldlinux.o \
>>                 --start-group libcom32.a --whole-archive
>> /home/gene/s/g/bios/com32/lib/libcom32core.a libldlinux.a --end-group
>> \
>>                 > ldlinux.map
>> ld:/home/gene/s/g/core/syslinux.ld:29: syntax error
>> make[3]: *** [ldlinux.elf] Error 1
>>
>>
>> core/syslinux.ld:29:    HIDDEN(__module_start = .);
>>
>> This would seem to indicate that the keyword HIDDEN is invalid in my
>> version.  A quick "git grep com32.ld" seems to show that com32.ld is
>> unused.
>>
>
> I just checked, HIDDEN has been added in binutils 2.23 release in late
> 2012. Should I just not port the commit
> 275a269ddec9f4d1b7a65f4f7c3e818401103d31 to the actually used linker
> scripts and leave the symbols not hidden?
>
> That's interesting, I don't know what's the purpose of
> com32/lib/com32.ld, it's just installed and never used. By looking
> into the history, it looks that it has been replaced by
> com32/lib/elf32.ld which was then split into arch-specific linker
> scripts. I guess it's a leftover.
>
> However, I don't know why it needs to be installed. This linker script
> installation has been introduced in 2004 by the commit
> 2d747a0e3e9d99cce544e4645370fcf7ef3e92ee. Maybe someone knows why it
> had to be installed? hpa?
>
>
> Celelibi

Alternative approach to these linker changes, including the ones
relevant to gcc-5:

https://github.com/geneC/syslinux/tree/linker

-- 
-Gene