[Numpy-discussion] OS X Lion: llvm: numpy and scipy

[David Cournapeau]

On Tue, Sep 20, 2011 at 5:13 AM, Samuel John <scipy at samueljohn.de> wrote:
> Ralf, thanks for your answer.
>
> However, in short:
>
>  I want `pip install numpy; pip install scipy` to work on OS X Lion without extra effort :-)
>
>
> On 19.09.2011, at 19:05, Ralf Gommers wrote:
>> Do you think it's possible to teach numpy to use different CC, CXX?
>>
>>> This is possible, but numpy probably shouldn't mess with these variables. As a user you can set them permanently by adding them to your bash_profile for example.
>
> The problem is that most things do work fine with the default gcc which has the llvm backend on OS X Lion (10.7) /usr/bin/gcc -> llvm-gcc-4.2. But somehow scipy has problems with that backend.
> I do not want to set CC CXX permanently.
> I made a homebrew formula for numpy, which takes care of these things. But the policy of the homebrew team is to avoid duplicates which can be installed via pip. Therefore I am asking for support if someone could point me to the place where the compiler is chosen. I'd propose to add an OS X 10.7 switch there in order to avoid the llvm.
>
>
>>> And the FFLAGS
>>
>> This needs to be solved. Perhaps the solution involves more wrappers for broken vecLib/Accelerate functions in scipy? Does anyone know which routines are broken on 10.7? For 10.6 I found this discussion helpful: http://www.macresearch.org/lapackblas-fortran-106. It is claimed there that while '-ff2c' fixes complex routines, it breaks SDOT when used with '-m64'. SDOT is used in linalg.
>
> I don't know nothing of such things. :-(
> If there is really something broken with vecLib/Accelerate, a ticket on Apple's bugtracker rdar should be opened.
>
>
>>> and the switch --fcompiler=gnu95 arg?
>>
>> This shouldn't be necessary if you only have gfortran installed.
>>
>
> Ah ok. Thanks!

I will try to look at this problem next week, when I will receive a
new laptop with Lion on it. If I forget about it, please ping me at
the end of next week, we need to fix this,

cheers,

David