Re: Using section flags to indicate strip or persistent sections

[Florian Weimer <fweimer@redhat.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
>
>   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