Another year in the quest to out-guess random C behavior.
Added macros Py_ADJUST_ERANGE1(X) and Py_ADJUST_ERANGE2(X, Y). The latter
is useful for functions with complex results. Two corrections to errno-
after-libm-call are attempted:
1. If the platform set errno to ERANGE due to underflow, clear errno.
Some unknown subset of libm versions and link options do this. It's
allowed by C89, but I never figured anyone would do it.
2. If the platform did not set errno but overflow occurred, force
errno to ERANGE. C89 required setting errno to ERANGE, but C99
doesn't. Some unknown subset of libm versions and link options do
it the C99 way now.
Bugfix candidate, but hold off until some Linux people actually try it,
with and without -lieee. I'll send a help plea to Python-Dev.
requires that errno ever get set, and it looks like glibc is already
playing that game. New rules:
+ Never use HUGE_VAL. Use the new Py_HUGE_VAL instead.
+ Never believe errno. If overflow is the only thing you're interested in,
use the new Py_OVERFLOWED(x) macro. If you're interested in any libm
errors, use the new Py_SET_ERANGE_IF_OVERFLOW(x) macro, which attempts
to set errno the way C89 said it worked.
Unfortunately, none of these are reliable, but they work on Windows and I
*expect* under glibc too.
The bug report title isn't correct, but was on the right track.
Rev 2.13 applied a patch intended to improve asinh and acosh, but the
author mistakenly replaced the body of asin with their new code for asinh.
See bug report for all the gory details.
This patch: (a) puts the "new" (as of 2.13) asinh code into the asinh
function; and, (b) repairs asin via what Abramowitz & Stegun say it should
be (which is probably the same as what 2.12 did for asin, although I got
tired of matching parentheses before being 100% sure of that -- and I don't
care! The source of the old code is a mystery, and I *know* why I picked
the new code.).
and a couple of functions that were missed in the previous batches. Not
terribly tested, but very carefully scrutinized, three times.
All these were found by the little findkrc.py that I posted to python-dev,
which means there might be more lurking. Cases such as this:
long
func(a, b)
long a;
long b; /* flagword */
{
and other cases where the last ; in the argument list isn't followed by a
newline and an opening curly bracket. Regexps to catch all are welcome, of
course ;)
Tim posted a long comment to python-dev (subject: "Controversial patch
(cmath)"; date: 6/29/00). The conclusion is that this whole module
stinks and this patch isn't perfect, but it's better than the acosh
and asinh we had, so let's check it in.
Fred Drake
Tim Peters
Martin v. Löwis
Andrew M. Kuchling
Peter Schneider-Kamp
Thomas Wouters
Guido van Rossum
Roger E. Masse