customize linker script fail when use gold linker

customize linker script fail when use gold linker

[陈云星]

Hi, folks:

I’m migrating from bfd linker to gold linker.

And my project has custom linker script:

====================================
SECTIONS
{
  memory_context_static_id :
  {
    KEEP(*(SORT(memory_context_static_id*)));
  }
  co_buffer :
  {
    KEEP(*(*CO_BUFFER_BEGIN*))
    KEEP(*(*COBUFFER*))
    KEEP(*(*CO_BUFFER_END*))
  }
  co_hook :
  {
    KEEP(*(*CO_HOOK_BEGIN*))
    KEEP(*(*COHOOK*))
    KEEP(*(*CO_HOOK_END*))
  }
}
INSERT AFTER .text;
====================================

when I migrate to gold linker, it failed with gold don’t recognize ‘INSERT’;

After some google search, this failed means gold linker  has no default script;

Then I try to dump the default script by : ld —verbose; and put above custom script in the dumped;

which also failed with error:

/usr/bin/ld.gold: error: /data/1/3_2_x_opt-gcc93/rpm/gold.lds:51:22: syntax error, unexpected '('                                        
/usr/bin/ld.gold: fatal error: unable to parse script file /data/1/3_2_x_opt-gcc93/rpm/gold.lds 

It seems the linker script can’t been correctly parsed by gold.

So, how can I do ?

Thanks your help :)

=====================================================
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}
======================================================

Re: customize linker script fail when use gold linker

[Fangrui Song]

On 2021-05-14, 陈云星 via Binutils wrote:
>Hi, folks:
>
>I’m migrating from bfd linker to gold linker.
>
>And my project has custom linker script:
>
>====================================
>SECTIONS
>{
>  memory_context_static_id :
>  {
>    KEEP(*(SORT(memory_context_static_id*)));
>  }
>  co_buffer :
>  {
>    KEEP(*(*CO_BUFFER_BEGIN*))
>    KEEP(*(*COBUFFER*))
>    KEEP(*(*CO_BUFFER_END*))
>  }
>  co_hook :
>  {
>    KEEP(*(*CO_HOOK_BEGIN*))
>    KEEP(*(*COHOOK*))
>    KEEP(*(*CO_HOOK_END*))
>  }
>}
>INSERT AFTER .text;
>====================================
>
>when I migrate to gold linker, it failed with gold don’t recognize ‘INSERT’;

gold doesn't support INSERT [BEFORE|AFTER].

Re: customize linker script fail when use gold linker

[Cary Coutant]

> when I migrate to gold linker, it failed with gold don’t recognize ‘INSERT’;
>
> After some google search, this failed means gold linker  has no default script;

Yes, because there is no default linker script, gold does not support
INSERT BEFORE or INSERT AFTER.

> Then I try to dump the default script by : ld —verbose; and put above custom script in the dumped;
>
> which also failed with error:
>
> /usr/bin/ld.gold: error: /data/1/3_2_x_opt-gcc93/rpm/gold.lds:51:22: syntax error, unexpected '('
> /usr/bin/ld.gold: fatal error: unable to parse script file /data/1/3_2_x_opt-gcc93/rpm/gold.lds
>
> It seems the linker script can’t been correctly parsed by gold.

>   .init           :
>   {
>     KEEP (*(SORT_NONE(.init)))
>   }

>   .fini           :
>   {
>     KEEP (*(SORT_NONE(.fini)))
>   }

Gold also does not support SORT_NONE. Try removing that.

Ideally, you should try to find a way to link your code without a
custom linker script at all. If you're using CO_BUFFER_BEGIN and
CO_BUFFER_END as bracketing sections to provide a start and stop
symbol, you can try using the linker-generated __start_COBUFFER and
__stop_COBUFFER symbols instead. Likewise for the COHOOK section.

-cary