[Cython] Bug: llabs not defined in vs2008

[Stefan Behnel]

Hi!

None of the core developers uses MSVC, so we generally rely on Windows
users to do their own testing and provide fixes.

Hogan, Christopher schrieb am 30.09.2015 um 00:03:
> I was trying to compile numpy v1.9.2 with Visual Studio 2008 and Cython
> 0.23.1.  This worked fine with Cython 0.22.x, but in 0.23.1 there are
> some changes in Cython/Utility/TypeConversion.c that seem to cause this
> error:
> 
> mtrand.obj : error LNK2019: unresolved external symbol llabs referenced
> in function __pyx_pf_6mtrand_11RandomState_24 choice
> 
> llabs is not available in vs2008, but it ends up taking that "#elif"
> branch in TypeConversion.c and defining __Pyx_sst_abs to be llabs.  I
> was able to fix this by swapping the order of the "#elif defined
> (_MSC_VER) ..."  block with the "#elif defined (__STDC_VERSION__) ... "
> block.

So, what you are saying is that VS-2008 is not C99 standards compliant
(what a surprise) but claims to be? Are you passing any C compiler flags
that requests C99 compliance?

The last changes in this area were here:

https://github.com/cython/cython/pull/403

The contributor claimed to be using MSVC 2008, too, so I wonder why you run
into this problem but he didn't.


> That probably won't fix the problem in all cases though.

To me, your proposed change seems a reasonable thing to do. What cases are
you thinking of?

Stefan