DOC, BUILD: make build_src more discoverable

1 files changed, 15 insertions, 0 deletions

diff --git a/doc/source/dev/development_environment.rst b/doc/source/dev/development_environment.rst
index ce571926e..9d618cc9f 100644
--- a/doc/source/dev/development_environment.rst
+++ b/doc/source/dev/development_environment.rst
@@ -96,6 +96,11 @@ installs a ``.egg-link`` file into your site-packages as well as adjusts the
 Other build options
 -------------------
 
+Build options can be discovered by running any of::
+
+    $ python setup.py --help
+    $ python setup.py --help-commands
+
 It's possible to do a parallel build with ``numpy.distutils`` with the ``-j`` option;
 see :ref:`parallel-builds` for more details.
 
@@ -106,6 +111,16 @@ source tree is to use::
     $ export PYTHONPATH=/some/owned/folder/lib/python3.4/site-packages
 
 
+NumPy uses a series of tests to probe the compiler and libc libraries for
+funtions. The results are stored in ``_numpyconfig.h`` and ``config.h`` files
+using ``HAVE_XXX`` definitions. These tests are run during the ``build_src``
+phase of the ``_multiarray_umath`` module in the ``generate_config_h`` and
+``generate_numpyconfig_h`` functions. Since the output of these calls includes
+many compiler warnings and errors, by default it is run quietly. If you wish
+to see this output, you can run the ``build_src`` stage verbosely::
+
+    $ python build build_src -v
+
 Using virtualenvs
 -----------------