Re: [PATCH v2] Add support for the --readnever command-line option (DWARF only)

[Pedro Alves <palves at redhat dot com>]

On 11/23/2017 05:21 PM, Sergio Durigan Junior wrote:

>>> +This option is currently limited to debug information in DWARF format.
>>> +For all other format, this option has no effect.
>>
>> How hard would it be to just make it work?  There's only stabs and mdebug
>> left, I think?  There should be a single a function somewhere that we can
>> add an early return.  And then we don't need to document this limitation...
>>
>> For example, in elf_symfile_read, we could just skip the elf_locate_sections
>> call.  In coffread.c we could skip reading stabs right after 
>>   bfd_map_over_sections (abfd, coff_locate_sections....);
>>
>> Looking for:
>>
>>  $ grep -h "^[a-z]*_build_psymtabs" gdb/
>>  coffstab_build_psymtabs (struct objfile *objfile,
>>  elfstab_build_psymtabs (struct objfile *objfile, asection *stabsect,
>>  stabsect_build_psymtabs (struct objfile *objfile, char *stab_name,
>>  mdebug_build_psymtabs (minimal_symbol_reader &reader,
>>  elfmdebug_build_psymtabs (struct objfile *objfile,
>>
>> finds all the relevant places.
>>
>> Maybe it wouldn't be that hard to make this be an objfile flag
>> afterall (like OBJF_READNOW is).  That'd make it possible
>> to add the location "-readnever" counterpart switch to add-symbol-file
>> too, BTW:

I meant "logical" instead of "location".  I was staring at
gdb/location.c at that time.  :-P

>>
>>  symfile.c:        if (strcmp (arg, "-readnow") == 0)
>>  symfile.c:        else if (strcmp (arg, "-readnow") == 0)
> 
> Hm, I'll look into this.  Just to make it clear: the idea is to have
> both a --readnever global option and also a OBJF_READNEVER specific to
> each objfile?

Sure, the idea is to do something similar to what's done for --readnow.

Thanks,
Pedro Alves