in fips mode, md5 is disabled. hence, ipython fails with

    hash_digest = hashlib.md5(code.encode("utf-8")).hexdigest()
ValueError: error:060800A3:digital envelope routines:EVP_DigestInit_ex:disabled for fips

this error.

A fix is changing md5 to sha256 in IPython/core/compilerop.py in this line. I can raise a pull request if the change looks fine.

Sounds OK to me, go ahead and make a PR :-)

As best I can tell, sha1 is supported in FIPS mode, if that's true, let's use that, instead. We're not using this for a cryptographically secure purpose, and sha256 is a bit slower, and generates a much longer string, most of which we will throw away, anyway - since we take only the first 12 characters.

Also, although it is used in a deprecated function, for now, md5 is also imported in IPython/utils/path.py. I created a bug to remove it for some future first time contributor.

Why not "Just" hex(abs(hash("""this is a string """))) if it's not cryptographically secure ?

Edit: (abs because python can give you a negative hex number prefixed with -)

hex(abs(hash())) may give you a shorter string if hash() happens to return a number close to 0. That may not be a problem, but it might mean that e.g. regexes looking for 12 hex characters don't work.

Ad, but we can pad to 12 with 0s then.

@ivanov: I somehow missed this thread because of the whole hoard of notifications from my github subscriptions.

I just verified sha1 is available in FIPS mode, I have created a PR which changes md5 to sha1. Thanks.