Re: Using section flags to indicate strip or persistent sections

["Jose E. Marchesi" <jose.marchesi@oracle.com>]

> * Nick Clifton via Gnu-gabi:
>
>>   We would like to suggest an extension the ELF section flags which can be
>>   used to indicate sections that should, or should not, be stripped when
>>   removing debug information.
>>
>>   The problem we are trying to address is that different stripping tools
>>   (strip, eu-strip, llvm-strip) have different heuristics for deciding
>>   which sections should be removed when stripping debug information.  In
>>   order to fix this we are proposing two new section flags:
>>
>>     GNU_SHF_CAN_BE_STRIPPED
>>     GNU_SHF_DO_NOT_STRIP

I think the "can be" in the GNU_SHF_CAN_BE_STRIPPED name is confusing
given the indicated semantics.

Wouldn't be better to call that flag GNU_SHF_STRIP instead?

>>   These would be set by the assembler and/or linker to indicate sections
>>   that should be removed when stripping and sections which must not be
>>   removed when stripping.  It would be an error if both flags were present
>>   on a given section, and if neither flag is present then the stripping
>>   tool would fall back on its built in heuristics.
>>
>>   In addition we need new flags for the assembler's .section directive
>>   (suggestion: 'D': can be stripped, 'K' do not strip).
>>   This email is to ask if you think that this idea has merit, and if so,
>>   are there any guidelines for writing and submitting a formal specification ?
>
> (Cc: list fixed, hence full quote.)
>
> I think making this explicit is a good idea in principle.  However, I'm
> not sure if the flags convey sufficient information to decide whether a
> section should be removed as part of debuginfo stripping.  I think that
> needs at least one flag that says, “this section should be removed or
> separated as part of default debuginfo processing”.
>
> Some use-cases involve non-removable non-allocated sections, too, but
> that would be something different.
>
> Thanks,
> Florian