Re: [PATCH] gdbsupport: bump unordered_dense library to 4.6.0

[Simon Marchi <simon.marchi@polymtl.ca>]

On 10/8/25 3:19 PM, Pedro Alves wrote:
> Hi!
> 
> On 2025-10-08 18:48, Hannes Domani wrote:
> 
>>> +// <memory_resource> includes <mutex>, which fails to compile if
>>> +// targeting GCC >= 13 with the (rewritten) win32 thread model, and
>>> +// targeting Windows earlier than Vista (0x600).  GCC predefines
>>> +// _REENTRANT when using the 'posix' model, and doesn't when using the
>>> +// 'win32' model.
>>> +#    if defined __MINGW64__ && defined __GNUC__ && __GNUC__ >= 13 && !defined _REENTRANT
>>> +// _WIN32_WINNT is guaranteed to be defined here because of the
>>> +// <cstdint> inclusion above.
>>> +#        ifndef _WIN32_WINNT
>>> +#            error "_WIN32_WINNT not defined"
>>> +#        endif
>>> +#        if _WIN32_WINNT < 0x600
>>> +#            define ANKERL_MEMORY_RESOURCE_IS_BAD() 1 // NOLINT(cppcoreguidelines-macro-usage)
>>> +#        endif
>>> +#    endif
>>> +#    ifndef ANKERL_MEMORY_RESOURCE_IS_BAD
>>> +#        define ANKERL_MEMORY_RESOURCE_IS_BAD() 0 // NOLINT(cppcoreguidelines-macro-usage)
>>> +#    endif
>>
>> This mentions '(rewritten) win32' and 'posix' thread models.
> 
> The win32 thread model was completely rewritten in GCC 13, that's what I meant
> by '(rewritten) win32'.  It seems like this isn't very common knowledge, which IMHO leads
> to people still using other models when they probably don't need to.
> 
> See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115105
> 
>> What about the 'mcf' thread model, 
> 
> No sure.  I've never used it.  Did that ever make it to GCC upstream?  I'm under the impression it did not.
> 
> I don't really know if there is still a point in using that model vs stock win32 since GCC 13.
> 
>> or is that meant with 'rewritten win32'?
> 
> No.
> 
> Pedro Alves
> 

I just remembered about this patch.  I was not sure if this discussion
was going to go further, so I didn't push the patch right away at the
time, but I just pushed it now.

In the mean time, there were some 4.7.0 and 4.8.0 releases, but I didn't
see anything we needed in there.

Simon