[Python-Dev] mingw32 and gc-header weirdness

["Martin v. Löwis"]

Roumen Petrov wrote:
> Martin v. Löwis wrote:
> [SNIP]
>> No. tim_one changed it to be long double in r25454 to support some
>> system that Dave Abrahams uses, so it needs to stay that way :-)
>>
>> However, we can certainly acknowledge that this is a bug in MingW,
>> and special case it. Either introduce a symbolic type gchead_align_t
>> which gets defined to just double on MingW, or put the #ifdef right
>> into the structure.
> 
> No this is not GCC bug. GCC support "hardware extended precision" as
> implement long double and mingw w32api implement long double functions.

And that exactly is the bug. GCC cannot simultaneously be
Windows-compatible, and also support extended precision floating point
under the name "long double".

> According to http://msdn.microsoft.com/en-us/library/9cx8xs15.aspx it is
> MSVC limitation.

Therefore, mingw should also implement that limitation, to be
binary-compatible with MSVC. Since binary compatibility is an explicit
goal of mingw, failing to provide binary compatibility is a bug.

Regards,
Martin