break cycles, which are a special problem when running generator tests
that provoke exceptions by invoking the .next() method of a named
generator-iterator: then the iterator is named in globs, and the
iterator's frame gets a tracekback object pointing back to globs, and
gc doesn't chase these types so the cycle leaks.
Also changed _run_examples() to make a copy of globs itself, so its
callers (direct and indirect) don't have to (and changed the callers
to stop making their own copies); *that* much is a change I've been
meaning to make for a long time (it's more robust the new way).
Here's a way to provoke the symptom without doctest; it leaks at a
prodigious rate; if the last two "source" lines are replaced with
g().next()
the iterator isn't named and then there's no leak:
source = """\
def g():
yield 1/0
k = g()
k.next()
"""
code = compile(source, "<source>", "exec")
def f(globs):
try:
exec code in globs
except ZeroDivisionError:
pass
while 1:
f(globals().copy())
After this change, running test_generators in an infinite loop still leaks,
but reduced from a flood to a trickle.
Good news: Some of this stuff is pretty sophisticated (read nuts), and
I haven't bumped into a bug yet.
Bad news: If I run the doctest in an infinite loop, memory is clearly
leaking.
Iterators list and Python-Dev; e.g., these all pass now:
def g1():
try:
return
except:
yield 1
assert list(g1()) == []
def g2():
try:
return
finally:
yield 1
assert list(g2()) == [1]
def g3():
for i in range(3):
yield None
yield None
assert list(g3()) == [None] * 4
compile.c: compile_funcdef and com_return_stmt: Just van Rossum's patch
to compile the same code for "return" regardless of function type (this
goes back to the previous scheme of returning Py_None).
ceval.c: gen_iternext: take a return (but not a yield) of Py_None as
meaning the generator is exhausted.
the next free valuestack slot, not to the base (in America, stacks push
and pop at the top -- they mutate at the bottom in Australia <winK>).
eval_frame(): assert that f_stacktop isn't NULL upon entry.
frame_delloc(): avoid ordered pointer comparisons involving f_stacktop
when f_stacktop is NULL.
attribute values, and make the logic surrounding the platform
annotations just a little easier to read. Also make the platform
notes appear in the generated page; they were supposed to, but did not.
I published it on the web as http://www.python.org/2.1/md5sum.py
so I thought I might as well check it in.
Works with Python 1.5.2 and later.
Works like the Linux tool ``mdfsum file ...'' except it doesn't take
any options or read stdin.
Jack Jansen
Steven M. Gava
Martin v. Löwis
Tim Peters
Andrew M. Kuchling
Eric S. Raymond
Fred Drake
Guido van Rossum