[Numpy-discussion] Numpy depends on OpenSSL ???

[Robert Kern]

On Wed, Sep 23, 2009 at 10:52, Mark Sienkiewicz <sienkiew at stsci.edu> wrote:
> I have discovered the hard way that numpy depends on openssl.
>
> I am building a 64 bit python environment for the macintosh.  I
> currently do not have a 64 bit openssl library installed, so the python
> interpreter does not have hashlib.  (hashlib gets its md5 function from
> the openssl library.)

There are builtin implementations that do not depend on OpenSSL.
hashlib should be using them for MD5 and the standard SHA variants
when OpenSSL is not available. Try "import _md5". But basically, we
expect you to have a reasonably complete standard library.

> The problem is in numpy/core/code_generators/genapi.py, where it appears
> to be trying to make an md5 hash of the declarations of some of the C
> functions.
>
> What is this hash used for?  Is there a particular reason that it needs
> to be cryptographically strong?

It is used for checking for changes in the API. While this use case
does not require all of the properties that would make a hash
cryptographically strong, it needs some of them.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless
enigma that is made terrible by our own mad attempt to interpret it as
though it had an underlying truth."
  -- Umberto Eco