Re: [PATCH v2 3/5] gdb/testsuite: Add gdb.arch/aarch64-mops-watchpoint.exp

[Thiago Jung Bauermann <thiago.bauermann@linaro.org>]

Hello Tom,

Tom de Vries <tdevries@suse.de> writes:

> On 5/21/24 23:03, Thiago Jung Bauermann wrote:
>> Hello Pedro,
>> Thank you for your review!
>> Pedro Alves <pedro@palves.net> writes:
>> 
>>>> Note this causes
>>>> +# a restart of GDB.
>>>
>>> Might want to apply a similar logic to can_spawn_for_attach, wrt gdb_exit.
>>> See the tail end of that function.  Maybe we can factor that out and
>>> reuse it.
>>
>> I looked into it, but I wasn't able to understand what is the problem
>> that gdb_exit causes. Does it mean that any require predicate that
>> restarts GDB needs to use that two-tier caching scheme?
>> 
>
> Let me try to explain the idea.  Consider two demonstrator test-cases:

<snip>

Thank you for the explanation and clear example. I understand the
problem now.

> This two-tier scheme is convenient for can_spawn_for_attach, because it's a pre-existing
> proc that didn't use gdb_exit and consequently was used in random places in test-cases,
> and also multiple times in a single test-case.
>
> For a proc like allow_aarch64_mops_tests, which is only used at the very start of a
> test-case, once, IMO it's not necessary, and not worth the effort of splitting up the
> proc.

Yes, I agree that this issue doesn't affect the require predicate proc.

> However, if we factor this approach out into a special variant, say
> gdb_caching_proc_with_gdb_exit or some such, then it could be done relatively easily.

If there are other caching procs that exit or restart GDB that are used
in the middle of testcases, then that is indeed a good idea.
-- 
Thiago