* unified the way intobject, longobject and mystrtoul handle
values around -sys.maxint-1.
* in general, trying to entierely avoid overflows in any computation
involving signed ints or longs is extremely involved. Fixed a few
simple cases where a compiler might be too clever (but that's all
guesswork).
* more overflow checks against bad data in marshal.c.
* 2.5 specific: fixed a number of places that were still confusing int
and Py_ssize_t. Some of them could potentially have caused
"real-world" breakage.
* list.pop(x): fixing overflow issues on x was messy. I just reverted
to PyArg_ParseTuple("n"), which does the right thing. (An obscure
test was trying to give a Decimal to list.pop()... doesn't make
sense any more IMHO)
* trying to write a few tests...
In general, C doesn't define anything about what happens when
an operation on a signed integral type overflows, and PyOS_strtol()
did several formally undefined things of that nature on signed
longs. Some version of gcc apparently tries to exploit that now,
and PyOS_strtol() could fail to detect overflow then.
Tried to repair all that, although it seems at least as likely to me
that we'll get screwed by bad platform definitions for LONG_MIN
and/or LONG_MAX now. For that reason, I don't recommend backporting
this.
Note that I have no box on which this makes a lick of difference --
can't really test it, except to note that it didn't break anything
on my boxes.
Silent change: PyOS_strtol() used to return the hard-coded 0x7fffffff
in case of overflow. Now it returns LONG_MAX. They're the same only on
32-bit boxes (although C doesn't guarantee that either ...).
both mystrtoul.c and longobject.c. Share the table instead. Also
cut its size by 64 entries (they had been used for an inscrutable
trick originally, but the code no longer tries to use that trick).
In rare cases of strings specifying true values near sys.maxint,
and oddball bases (not decimal or a power of 2), int(string, base)
could deliver insane answers. This repairs all such problems, and
also speeds string->int significantly. On my box, here are %
speedups for decimal strings of various lengths:
length speedup
------ -------
1 12.4%
2 15.7%
3 20.6%
4 28.1%
5 33.2%
6 37.5%
7 41.9%
8 46.3%
9 51.2%
10 19.5%
11 19.9%
12 23.9%
13 23.7%
14 23.3%
15 24.9%
16 25.3%
17 28.3%
18 27.9%
19 35.7%
Note that the difference between 9 and 10 is the difference between
short and long Python ints on a 32-bit box. The patch doesn't
actually do anything to speed conversion to long: the speedup is
due to detecting "unsigned long" overflow more quickly.
This is a bugfix candidate, but it's a non-trivial patch and it
would be painful to separate the "bug fix" from the "speed up" parts.
must be enabled here, otherwise the errno we set on overflows is not
the errno that's being read by compile.c. Wonder how many other files
that do their own "#include config.h" need this too :-(
(Because of the structure of autoconf, it's not so simple to get this
into config.h...)
bltinmodule.c: fixed coerce() nightmare in ternary pow().
modsupport.c (initmodule2): pass METH_FREENAME flag to newmethodobject().
pythonrun.c: move flushline() into and around print_error().
Armin Rigo
Tim Peters
Neal Norwitz
Martin v. Löwis
Jack Jansen
Guido van Rossum
Thomas Wouters