Re: README.MacOS & 64bit buids [was: Clang!]

[Richard Campbell]

On Feb 3, 2011, at 9:03 AM, Ben Abbott wrote:

> On Feb 1, 2011, at 12:36 PM, Richard Campbell wrote:
> 
>> octave:2> octave_config_info.CC
>> ans = clang
>> octave:3> octave_config_info.CXX
>> ans = llvm-g++
>> octave:4> octave_config_info.FC
>> ans = gfortran
>> octave:5> octave_config_info.config_opts
>> ans = '--disable-docs' '--with-blas=-lBLASWRAP' 'CC=clang' 'CFLAGS=-arch 
>> x86_64' 'LDFLAGS=-arch x86_64' 'CPPFLAGS=-arch x86_64 -D_REENTRANT' 
>> 'CXX=llvm-g++' 'FFLAGS=-arch x86_64'
>> 
>> It works! I also tried it with CXX="clang" but it gave a bunch of warnings 
>> and then hung during the build. From what I gather, c++ support from Clang 
>> is still highly experimental, although six months ago it was completely 
>> nonexistent. LLVM is working beautifully though. I might try with 
>> llvm-gfortran as well.
>> 
>> Campbell
> 
> Richard,
> 
> I noticed the manual build instructions include a description for 64bit 
> dependencies and instructions for building 32 bit Octave.
> 
> I'd like to split the instructions into sections for both 32bit and 64bit.
> 
> I assume that for a 32bit fftw I just need to change ...
> 
>       export CFLAGS="-arch i686 -arch x86_64" 
> 
> ... to ...
> 
>       export CFLAGS="-m32"
> 
> For a 64bit build of Octave is it sufficient to ...
> 
>       export CC="clang"
>       export CXX="llvm-g++"
>       export FC="/usr/bin/gfortran"
>       export CFLAGS="-arch x86_64"
>       export FFLAGS="$CFLAGS"
>       export CPPFLAGS="-arch x86_64 -D_REENTRANT -D__LISTS__"
>       export LDFLAGS="-arch x86_64"
>       ./configure --disable-readline --disable-docs
> 
> The "-D__LISTS__" option is needed to avoid the FLTK problem mention on the 
> list below.
> 
>       
> https://mailman.cae.wisc.edu/pipermail/octave-maintainers/2011-February/022708.html
> 
> I'f this looks ok to you, I'll modify README.MacOS.
> 
> Ben

No, don't change the dependencies line. "-arch i686 -arch x86_64" builds the 
dependency as a 32- and 64-bit universal binary, not just as 64-bit. It works 
for linking to either types of code. If "-arch i686" appeared by itself, this 
would be equivalent to "-m32". Any dependencies which CAN compile as universal 
binaries SHOULD be, in order to avoid having to recompile them in the future 
when you install other code beside Octave. In particular I use FFTW for Octave 
(32 bit) as well as my C code (64 bit only). If the FFTW library were 32 or 64 
bit only I'd have to recompile it all the time.

Campbell