Re: [pushed] gdb: change blockvector::contains() to handle blockvectors with "holes"

[Tom de Vries <tdevries@suse.de>]

On 12/3/25 10:31 PM, Jan Vraný wrote:
> On Wed, 2025-12-03 at 12:36 -0700, Tom Tromey wrote:
>>>>>>> "Jan" == Jan Vraný <Jan.Vrany@labware.com> writes:
>>
>>>> FWIW it seems to me that the blockvector should just have a single
>>>> lookup function, and it should be used to find precisely the code block
>>>> containing the given address.  That is, it should never return the
>>>> static or global block, since those aren't really "code" but instead
>>>> just containing scopes.  This is the direction I was trying to head by
>>>> removing calls to map(); the one remaining call is one of these weird
>>>> ones...
>>
>> Jan> I agree, I just do not really understand why there was the
>> Jan> difference in first place.
>>
>> I don't really, either.  That code is pretty old, though, and some of
>> the older code is pretty questionable.  Like sometimes problems with
>> debug readers were worked around in core code rather than being solved
>> in the reader, abstractions were very leaky (or in this case
>> nonexistent), etc.
>>
>> Jan> In fact, it seems that it matters - I've got a report that this
>> Jan> commit caused regression on arm (still investigating, I do not have
>> Jan> armhf system at hand, so need to set it up first).
>>
>> My current attempt at cleanups here also run into some regressions that
>> I wasn't really expecting :(
>>
>> Anyway I'd find it interesting to learn what the ARM regression is
>> about.
> 
> Yeah, it's weird. The report is here:
> 
> https://linaro.atlassian.net/browse/GNU-1767
> 
> I did not yet managed to reproduce it. It does not seem to manifest Debian
> armhf running on QEMU. I'm not familiar with ARM ecosystem myself and
> I do not know yet how to arrive at working "armv8l" system. I'll let you
> know when I learn more but just now I'm running out of ideas on how to
> debug this :(
> 

I bisected this PR ( 
https://sourceware.org/bugzilla/show_bug.cgi?id=33679 ) to this commit.

Are the regressions you mention the same issue?

Thanks,
- Tom

> Jan
> 
>>
>> Tom
>