Re: How to build ATLAS libraries with mingw gfortran on cygwin

[Benjamin Lindner]

Tatsuro MATSUOKA wrote:
> Hello Benjamin
>
> This is essentially the ATLAS issue but you have already solved this problem.
>
> I have been so far used the ATLAS libraries built using the cygwin GCC-4 and 
> used the libf77blas.a and
> libatlas.a. This might be illegal because the cygwin complier is not compatible 
> to Mingw one.
> However no problem has been occurred in octave 3.0.x.  

I wouldn't term it illegal and I think that the cygwin compiler is 
indeed compatible here, since you create a static library i.e. only 
object code. So you have to just make sure to use the same gcc version, 
since sytem libraries may be incompatible across different versions.
> I have tried the same procedure on the octave 3.2.0, configure script reject to 
> use the libf77blas.a
> and libatlas.a generated by cygwin GCC-4.

Does it?
I seem to have no problems here.
What is the error message?

> I have tried to build atlas libraries  -Si nocygwin 1.
> However gcc-mingw on cygwin is still GCC-3.4.4 so that we cannot use for Mingw 
> GCC-4 because gfortran
> is not compatible to g77.

True, but I think I saw that there is a native gcc-4 available for 
cygwin installable via cygwin's setup.exe. I believe it's also a 4.3.x 
version.

> To solve this, one has to use native GCC-4 Mingw compiler for ATLAS build on 
> cygwin.
>
> I have tried this but I cannot solved to translate cygwin path to windows path.
>
> It will be grateful for me if you will give some suggestions to me.

Here is what I did.
I built myself a native cygwin gcc of version 4.3.0 and used it to build 
atlas.
The creation of the shared libraries I do with the native mingw gcc.
Building a cygwin gcc is straightforward,
1) download gcc-core-4.3.0.tar.bz2 and gcc-fortran-4.3.0.tar.bz2
2) configure and set a useful prefix to have a seprarate installation 
tree, and configure for gcc and gfortran only (that's all you need for 
atlas)
3) make && make install

Have a look at the attached quick-and-dirty script I used

This worked for me so far.
What's not considered here yet is a multi-threaded build.

benjamin

#!/usr/bin/sh

BUILDDIR=.build_cygwin_gcc-3.3.3

TOPDIR=`pwd`

SRCDIR=gcc-4.3.0

unpack()
{
   tar xjvf gcc-core-4.3.0.tar.bz2
   tar xjvf gcc-fortran-4.3.0.tar.bz2
}

mkdirs()
{
   rm -rf $BUILDDIR
   mkdir $BUILDDIR
}

conf()
{
   cd $BUILDDIR && ${TOPDIR}/${SRCDIR}/configure --srcdir=${TOPDIR}/${SRCDIR} \
        --prefix=/opt/gcc-4.3.0 \
        --with-cpu=i686 \
        --enable-languages=c,fortran \
        --enable-version-specific-runtime-libs \
        --disable-shared \
        --disable-nls
}

build()
{
   cd $BUILDDIR && make
}

install()
{
   cd $BUILDDIR && make install
}

$*