Hello. Starting from a freshly installed cygwin, I have built Python 2.5, ATLAS and LAPACK all from source using gcc 3.4.4 (cygming special) for both the C and f77 compilers. Now I am trying to build NumPy from SVN. I have edited site.cfg so that python setup.py config --compiler=mingw32 finds all of the linear algebra packs and completes without error. Then I fire off python setup.py build --compiler=mingw32 and I soon get (while building extension numpy.random.mtrand) _configtest.c:7:2: #error No _WIN32 which is not immediately fatal but definitely a concern. Soon after, building numpy.core.multiarray gives me this: building 'numpy.core.multiarray' extension compiling C sources C compiler: gcc -mno-cygwin -mdll -O -Wall creating build/temp.cygwin-1.5.21-i686-2.5 creating build/temp.cygwin-1.5.21-i686-2.5/numpy creating build/temp.cygwin-1.5.21-i686-2.5/numpy/core creating build/temp.cygwin-1.5.21-i686-2.5/numpy/core/src compile options: '-Ibuild/src.cygwin-1.5.21-i686-2.5/numpy/core/src -Inumpy/core/include -Ibuild/src.cygwin-1.5.21-i686-2.5/numpy/core -Inumpy/core/src -Inumpy/core/include -I/usr/local/include/python2.5 -c' gcc -mno-cygwin -mdll -O -Wall -Ibuild/src.cygwin-1.5.21-i686-2.5/numpy/core/src -Inumpy/core/include -Ibuild/src.cygwin-1.5.21-i686-2.5/numpy/core -Inumpy/core/src -Inumpy/core/include -I/usr/local/include/python2.5 -c numpy/core/src/multiarraymodule.c -o build/temp.cygwin-1.5.21-i686-2.5/numpy/core/src/multiarraymodule.o In file included from /usr/local/include/python2.5/Python.h:57, from numpy/core/src/multiarraymodule.c:18: /usr/local/include/python2.5/pyport.h:226:24: sys/select.h: No such file or directory In file included from /usr/local/include/python2.5/Python.h:57, from numpy/core/src/multiarraymodule.c:18: /usr/local/include/python2.5/pyport.h:226:24: sys/select.h: No such file or directory I am puzzzled, because /usr/include/sys/select.h does exist. But maybe that's not what pyport.h is actually looking for? I've been banging away at this for several hours, so I must be doing something silly. Any help will be much appreciated. Thanks! _________________________________________________________________ Express yourself - download free Windows Live Messenger themes! http://clk.atdmt.com/MSN/go/msnnkwme0020000001msn/direct/01/?href=http://imagine-msn.com/themes/vibe/default.aspx?locale=en-us&source=hmtagline