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

[Pedro Alves <pedro@palves.net>]

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