Re: [PATCHv3] gdb: resolve class name via DW_AT_signature in cooked index

[Andrew Burgess <aburgess@redhat.com>]

Simon Marchi <simark@simark.ca> writes:

> On 2026-09-15 11:55, Simon Marchi wrote:
>> Having a bad parent is rare, that would only happen when some
>> (nameless) type has a DW_AT_signature and the matching type unit can't
>> be found.  That would be a buggy producer that "forgets" to add the
>> necessary type units.
>> 
>> But the basic case where the name fixup is needed isn't an error case,
>> it's just what happens when using clang with -fdebug-types-section,
>> since structures/classes are nameless:
>> 
>> 0x0000099e:   DW_TAG_structure_type
>>                 DW_AT_declaration [DW_FORM_flag_present]        (true)
>>                 DW_AT_signature [DW_FORM_ref_sig8]      (0xdf1329ababfff8ca)
>> 
>> So I suppose you'll get one fixup to do per structure/class type.
>> 
>> Doing the fixups in parallel is easy, since it's just looking up the
>> signature -> maps, and the "finalize" step already exists, so why not.
>
> I tested this patch on a big program (Blender).  I moved the deferred
> name computation to set_contents (done serially).  It takes 0.014
> seconds to do it for 820602 names.  So yeah, I'm fine if you want to
> move it to set_contents (done serially) for simplicity.

I'd already written v4 before I read this reply.  In v4 I do have the
cleanup performed in parallel, though this does add a little more
complexity into cooked_index::set_contents.  You'll have to let me know
what you think, I can always go back to the approach you're proposing
here if you don't like v4.

Thanks,
Andrew