Hi all

I'm trying to get an idea if Extended float is/can actually be 80bit? I have FPC built under Linux x64 and it works fine (co-processor command are actually used).

But I haven't found any reliable information about Win64 support. Brief FPC source grepping showed FPC_HAS_TYPE_EXTENDED define, but I haven't managed to find where it is defined.

-- Regards,
Denis Golovan

denisgolovan via fpc-pascal schrieb am
Di., 25. Feb. 2020, 23:01:

The Extended type is not available for x86_64-win64. You either need to use Double or the software floating point support in unit sfpux80 (though that is only available in 3.2 and newer).

Please note that you'll have the same problem on any non-x86 platform as that type only exists there (and m68k).

Regards,
Sven

The Extended type is not available for x86_64-win64. You either need to use Double or the software floating point support in unit sfpux80 (though that is only available in 3.2 and newer).

So, Linux x64 having hardware Extended support is just an exception? Or maybe it's possible to build a custom x86_64-win64 compiler with that define enabled?

Please note that you'll have the same problem on any non-x86 platform as that type only exists there (and m68k).

Yes. I am perfectly ok with Intel only.

-- Regards,
Denis Golovan

denisgolovan schrieb am Mi., 26. Feb. 2020, 11:38:

No, Win64 is the exception. All other x86_64 targets support it, but Microsoft decided to deprecate it.

Or maybe it's possible to build a custom x86_64-win64 compiler with that

define enabled?

In theory yes, but it's not recommended, because Microsoft does not recommend it (not to mention that it isn't even remotely tested as much as the normal Win64 target).

Regards,
Sven

In theory yes, but it's not recommended, because Microsoft does not recommend it (not to mention that it isn't even remotely tested as much as the normal Win64 target). Regards, Sven

Got it. Thanks for the clarification.

-- Regards,
Denis Golovan

Le 26.02.20 à 15:11, denisgolovan via fpc-pascal a écrit :

Well, well... Does it means that if one have scientific computations needing the extended type available on an Intel based processor with time constraints forbiding software emulation, one have to rest under a 32 bits version of windows ? Hoping/praying that 64 bits Intel based linuxes running fpc software will never experience such a monumental regression of Windows - what a nightmare ! Is Freddy Krueger so near us ?

Cheers, Ched'

All modern "number crunching" approaches (e.g. GPUs or AVX-512 do not support the extended type, so I doubt there is really a relevant number of use cases for the extended type.