[Python-Dev] 2.2.1c1 platform reports. (original) (raw)

Tim Peters tim.one@comcast.net
Fri, 22 Mar 2002 18:57:43 -0500

[Martin]

Is that the final text? My copy says

On a domain error, the function returns an implementation-defined value; if the integer expression matherrhandling & MATHERRNO is nonzero, the integer expression errno acquires the value EDOM; if the integer expression matherrhandling & MATHERREXCEPT is nonzero, the ``invalid'' floating-point exception is raised. but it comes from a draft only (99-04).

Mine also comes from a draft, dated 2000-08-07. Jeremy bought the final std, but good luck hassling him to look stuff up for us .

If this is what C99 says, you actually can tell, in C, whether checking errno will help indicating the error.

And when it doesn't, we're back to guessing. We already take advantage of sqrt(-1) setting EDOM on those platforms where it does. I don't see any simplification.

If the C implementation also implements Annex F, IEEE-754 fans should be satisfied, no?

Python doesn't know anything about Annex F now -- those facilities may as well not exist given our current code. Python's users are in two very different camps too: some want sqrt(-1) to blow up, and others want to get back a NaN without exception. Similarly for overflow and divide-by-zero, etc. C99 + Annex F is, from Python's current POV, just another unique platform Python knows nothing about.