Jeffrey Harper added the comment:
Martin,
Thanks for your response. I didn't know it was possible to pass freevars and
cellvars to new.code. I think the documentation needs to be updated. The
documentation for 2.7.3 located at
http://docs.python.org/library/new.html?highligh
Jeffrey Harper added the comment:
The marshal loads and dumps don't seem to be necessary to reproduce the crash.
On both the Windows Vista and Ubuntu Linux systems, the crash still occurred
when I replaced:
mcopy_code = loads(dumps(code))
with:
mcopy_code = code #loads(dumps
New submission from Jeffrey Harper :
I've attached a script that crashes the Python interpreter.
I can get the crash to occur under Windows Vista with this version of Python:
C:\tmp\remote>c:\Python27\python.exe
Python 2.7.1 Stackless 3.1b3 060516 (release27-maint, Jan 1 2011,
Jeffrey Harper added the comment:
Here's a patch against the version of test_peepholer.py in 3.2rc3. It verifies
that expressions like the following are optimized:
3*-4
(1,-2,3)
a in {1,-2,3)
--
keywords: +patch
Added file: http://bugs.python.org/file20787/test_peepholer.
Jeffrey Harper added the comment:
I think r82043 may also explain why 3.1.3 can fold the expression 2 * -3 into
-6 while 3.2rc3 cannot.
# test.py
from dis import dis
def y(): 2 * -3
print("dis y:")
dis(y)
C:\tmp>c:\Python32\python.exe --version
Python 3.2rc3
C:\tm
Jeffrey Harper added the comment:
I have also determined that negative elements interfere with the frozenset
optimization described in issue6690. http://bugs.python.org/issue6690.
Here's an example program:
# test.py
from dis import dis
def x(var): return var in {1,2,3} # Note curly b
New submission from Jeffrey Harper :
In Python 3.2, a tuple like (1,-2,3) will not be optimized into a constants at
compile time. The tuple is built at run-time. Earlier versions of Python
optimized these tuples at compile time.
Here's an example program.
# test.py
from dis import dis
New submission from Jeffrey Harper :
When a bytes object is pickled with 3.1 and then unpickled with 2.7, the
results are incorrect. The example below shows that pickling
b'abcdefg' in 3.1 and then unpickling in 2.7 produces the string
'[97L, 98L, 99L, 100L, 101L, 102L, 103L]&#
