In cyclic gc, clear weakrefs to unreachable objects before allowing any
Python code (weakref callbacks or __del__ methods) to run.
This is a critical bugfix, affecting all versions of Python since weakrefs
were introduced. I'll backport to 2.3.
exposed in header files. Fixed a few comments in these headers.
As we might have expected, writing down invariants systematically exposed a
(minor) bug. In this case, function objects have a writeable func_code
attribute, which could be set to code objects with the wrong number of
free variables. Calling the resulting function segfaulted the interpreter.
Added a corresponding test.
today. pyconfig.h can override it if not, and can also override
Py_IS_INFINITY now. Py_IS_NAN and Py_IS_INFINITY are overridden now
for Microsoft compilers, using efficient MS-specific spellings.
decoding incomplete input (when the input stream is temporarily exhausted).
codecs.StreamReader now implements buffering, which enables proper
readline support for the UTF-16 decoders. codecs.StreamReader.read()
has a new argument chars which specifies the number of characters to
return. codecs.StreamReader.readline() and codecs.StreamReader.readlines()
have a new argument keepends. Trailing "\n"s will be stripped from the lines
if keepends is false. Added C APIs PyUnicode_DecodeUTF8Stateful and
PyUnicode_DecodeUTF16Stateful.
This checkin is adapted from part 2 (of 3) of Trevor Perrin's patch set.
BACKWARD INCOMPATIBILITY: SHIFT must now be divisible by 5. AFAIK,
nobody will care. long_pow() could be complicated to worm around that,
if necessary.
long_pow():
- BUGFIX: This leaked the base and power when the power was negative
(and so the computation delegated to float pow).
- Instead of doing right-to-left exponentiation, do left-to-right. This
is more efficient for small bases, which is the common case.
- In addition, if the exponent is large (more than FIVEARY_CUTOFF
digits), precompute [a**i % c for i in range(32)], and go left to
right 5 bits at a time.
l_divmod():
- The signature changed so that callers who don't want the quotient,
or don't want the remainder, can pass NULL in the slot they don't
want. This saves them from having to declare a vrbl for unwanted
stuff, and remembering to decref it.
long_mod(), long_div(), long_classic_div():
- Adjust to new l_divmod() signature, and simplified as a result.
This checkin is adapted from part 1 (of 3) of Trevor Perrin's patch set.
x_mul()
- sped a little by optimizing the C
- sped a lot (~2X) if it's doing a square; note that long_pow() squares
often
k_mul()
- more cache-friendly now if it's doing a square
KARATSUBA_CUTOFF
- boosted; gradeschool mult is quicker now, and it may have been too low
for many platforms anyway
KARATSUBA_SQUARE_CUTOFF
- new
- since x_mul is a lot faster at squaring now, the point at which
Karatsuba pays for squaring is much higher than for general mult
happen in 2.3, but nobody noticed it still was getting generated (the
warning was disabled by default). OverflowWarning and
PyExc_OverflowWarning should be removed for 2.5, and left notes all over
saying so.
unicodedata.east_asian_width(). You can still implement your own
simple width() function using it like this:
def width(u):
w = 0
for c in unicodedata.normalize('NFC', u):
cwidth = unicodedata.east_asian_width(c)
if cwidth in ('W', 'F'): w += 2
else: w += 1
return w
or broken by basic ctype functions in 4.4BSD descendants. This
will be fixed in their future development branches but they'll keep
the POSIX-incompatibility for their backward-compatiblities in near
future.
to NULL during the lifetime of the object.
* listobject.c nevertheless did not conform to the other invariants,
either; fixed.
* listobject.c now uses list_clear() as the obvious internal way to clear
a list, instead of abusing list_ass_slice() for that. It makes it easier
to enforce the invariant about ob_item == NULL.
* listsort() sets allocated to -1 during sort; any mutation will set it
to a value >= 0, so it is a safe way to detect mutation. A negative
value for allocated does not cause a problem elsewhere currently.
test_sort.py has a new test for this fix.
* listsort() leak: if items were added to the list during the sort, AND if
these items had a __del__ that puts still more stuff into the list,
then this more stuff (and the PyObject** array to hold them) were
overridden at the end of listsort() and never released.
mutation during list.sort() used to rely on that listobject.c always
NULL'ed ob_item when ob_size fell to 0. That's no longer true, so the
test for list mutation during a sort is no longer reliable. Changed the
test to rely instead on that listobject.c now never NULLs-out ob_item
after (if ever) ob_item gets a non-NULL value. This new assumption is
also documented now, as a required invariant in listobject.h.
The new assumption allowed some real simplification to some of the
hairier code in listsort(), so is a Good Thing on that count.
Rewrote Py_RETURN_{NONE, TRUE, FALSE} to expand to comma expressions
rather than "do {} while(0)" thingies. The OP complained because he
likes using MS /W4 sometimes, and then all his uses of these things
generate nuisance warnings about testing a constant expression (in
the "while(0)" part). Comma expressions don't have this problem
(although it's a lucky accident that comma expressions suffice for these
macros!).
- weakref.ref and weakref.ReferenceType will become aliases for each
other
- weakref.ref will be a modern, new-style class with proper __new__
and __init__ methods
- weakref.WeakValueDictionary will have a lighter memory footprint,
using a new weakref.ref subclass to associate the key with the
value, allowing us to have only a single object of overhead for each
dictionary entry (currently, there are 3 objects of overhead per
entry: a weakref to the value, a weakref to the dictionary, and a
function object used as a weakref callback; the weakref to the
dictionary could be avoided without this change)
- a new macro, PyWeakref_CheckRefExact(), will be added
- PyWeakref_CheckRef() will check for subclasses of weakref.ref
This closes SF patch #983019.
The builtin eval() function now accepts any mapping for the locals argument.
Time sensitive steps guarded by PyDict_CheckExact() to keep from slowing
down the normal case. My timings so no measurable impact.
The LaTeX is untested (well, so is the new API, for that matter).
Note that I also changed NULL to get spelled consistently in concrete.tex.
If that was a wrong thing to do, Fred should yell at me.
New include file timefuncs.h exports private API function
_PyTime_DoubleToTimet() from timemodule.c. timemodule should export
some other functions too (look for painful bits in datetimemodule.c).
Added insane-argument checking to datetime's assorted fromtimestamp()
and utcfromtimestamp() methods. Added insane-argument tests of these
to test_datetime, and insane-argument tests for ctime(), localtime()
and gmtime() to test_time.
iswide() for east asian width manipulation. (Inspired by David
Goodger, Reviewed by Martin v. Loewis)
- Move _PyUnicode_TypeRecord.flags to the end of the struct so that
no padding is added for UCS-4 builds. (Suggested by Martin v. Loewis)
(Code contributed by Jiwon Seo.)
The documentation portion of the patch is being re-worked and will be
checked-in soon. Likewise, PEP 289 will be updated to reflect Guido's
rationale for the design decisions on binding behavior (as described in
in his patch comments and in discussions on python-dev).
The test file, test_genexps.py, is written in doctest format and is
meant to exercise all aspects of the the patch. Further additions are
welcome from everyone. Please stress test this new feature as much as
possible before the alpha release.
realloc(). This is achieved by tracking the overallocation size in a new
field and using that information to skip calls to realloc() whenever
possible.
* Simplified and tightened the amount of overallocation. For larger lists,
this overallocates by 1/8th (compared to the previous scheme which ranged
between 1/4th to 1/32nd over-allocation). For smaller lists (n<6), the
maximum overallocation is one byte (formerly it could be upto eight bytes).
This saves memory in applications with large numbers of small lists.
* Eliminated the NRESIZE macro in favor of a new, static list_resize function
that encapsulates the resizing logic. Coverting this back to macro would
give a small (under 1%) speed-up. This was too small to warrant the loss
of readability, maintainability, and de-coupling.
* Some functions using NRESIZE had grown unnecessarily complex in their
efforts to bend to the macro's calling pattern. With the new list_resize
function in place, those other functions could be simplified. That is
being saved for a separate patch.
* The ob_item==NULL check could be eliminated from the new list_resize
function. This would entail finding each piece of code that sets ob_item
to NULL and adding a new line to invalidate the overallocation tracking
field. Rather than impose a new requirement on other pieces of list code,
it was preferred to leave the NULL check in place and retain the benefits
of decoupling, maintainability and information hiding (only PyList_New()
and list_sort() need to know about the new field). This approach also
reduces the odds of breaking an extension module.
(Collaborative effort by Raymond Hettinger, Hye-Shik Chang, Tim Peters,
and Armin Rigo.)
semantics to include subtypes. Most concrete object APIs then had
a Py<type>_CheckExact() macro added to test for an object's type
not including subtypes.
The PyDict_CheckExact() macro wasn't created at that time, so I've added
it for API completeness/symmetry - even though nobody has complained
about its absence in the time since 2.2 was released.
Not a backport candidate.
with most other concrete object checks, but the docs weren't brought into
line.
PyList_CheckExact() was added at 2.2 but never documented.
backport candidate.
bit by checking the value of UCHAR_MAX in Include/Python.h. There was a
check in Objects/stringobject.c. Remove that. (Note that we don't define
UCHAR_MAX if it's not defined as the old test did.)
* Add more tests
* Refactor and neaten the code a bit.
* Rename union_update() to update().
* Improve the algorithms (making them a closer to sets.py).
Also SF patch 843455.
This is a critical bugfix.
I'll backport to 2.3 maint, but not beyond that. The bugs this fixes
have been there since weakrefs were introduced.
* Install the unittests, docs, newsitem, include file, and makefile update.
* Exercise the new functions whereever sets.py was being used.
Includes the docs for libfuncs.tex. Separate docs for the types are
forthcoming.
The embed2.diff patch solves the user's problem by exporting the missing
symbols from the Python core so Python can be embedded in another Cygwin
application (well, at lest vim).
A new API (only accessible from C) to interrupt a thread by sending it
an exception. This is not always effective, but might help some people.
Requested by Just van Rossum and Alex Martelli. It is intentional
that you have to write your own C extension to call it from Python.
Docs will have to wait.
the purpose. Increased my claim to two bits, hoping that nobody
will complain about it. I'm taking the highest two bits, whatever
the integer word size may be.
The compiler was reseting the list comprehension tmpname counter for each function, but the symtable was using the same counter for the entire module. Repair by move tmpname into the symtable entry.
Bugfix candidate.
* Can now test for basic blocks.
* Optimize inverted comparisions.
* Optimize unary_not followed by a conditional jump.
* Added a new opcode, NOP, to keep code size constant.
* Applied NOP to previous transformations where appropriate.
Note, the NOP would not be necessary if other functions were
added to re-target jump addresses and update the co_lnotab mapping.
That would yield slightly faster and cleaner bytecode at the
expense of optimizer simplicity and of keeping it decoupled
from the line-numbering structure.
new line.
New pvt API function _Py_PrintReferenceAddresses(): Prints only the
addresses and refcnts of the live objects. This is always safe to call,
because it has no dependence on Python's C API.
Py_Finalize(): If envar PYTHONDUMPREFS is set, call (the new)
_Py_PrintReferenceAddresses() right before dumping final pymalloc stats.
We can't print the reprs of the objects here because too much of the
interpreter has been shut down. You need to correlate the addresses
displayed here with the object reprs printed by the earlier
PYTHONDUMPREFS call to _Py_PrintReferences().
New functions:
unsigned long PyInt_AsUnsignedLongMask(PyObject *);
unsigned PY_LONG_LONG) PyInt_AsUnsignedLongLongMask(PyObject *);
unsigned long PyLong_AsUnsignedLongMask(PyObject *);
unsigned PY_LONG_LONG) PyLong_AsUnsignedLongLongMask(PyObject *);
New and changed format codes:
b unsigned char 0..UCHAR_MAX
B unsigned char none **
h unsigned short 0..USHRT_MAX
H unsigned short none **
i int INT_MIN..INT_MAX
I * unsigned int 0..UINT_MAX
l long LONG_MIN..LONG_MAX
k * unsigned long none
L long long LLONG_MIN..LLONG_MAX
K * unsigned long long none
Notes:
* New format codes.
** Changed from previous "range-and-a-half" to "none"; the
range-and-a-half checking wasn't particularly useful.
New test test_getargs2.py, to verify all this.
Arranged that all the objects exposed by __builtin__ appear in the list
of all objects. I basically peed away two days tracking down a mystery
leak in sys.gettotalrefcount() in a ZODB app (== tons of code), because
the object leaking the references didn't appear in the sys.getobjects(0)
list. The object happened to be False. Now False is in the list, along
with other popular & previously missing leak candidates (like None).
Alas, we still don't have a choke point covering *all* Python objects,
so the list of all objects may still be incomplete.
_Py_AddToAllObjects() that simply inserts an object at the front of
the doubly-linked list of all objects. Changed PyType_Ready() (the
closest thing we've got to a choke point for type objects) to call
that.
variables to store internal data. As a result, any atempts to use the
unicode system with multiple active interpreters, or successive
interpreter executions, would fail.
Now that information is stored into members of the PyInterpreterState
structure.
with an indented code block but no newline would raise SyntaxError.
This would have been a four-line change in parsetok.c... Except
codeop.py depends on this behavior, so a compilation flag had to be
invented that causes the tokenizer to revert to the old behavior;
this required extra changes to 2 .h files, 2 .c files, and 2 .py
files. (Fixes SF bug #501622.)
Raymond Hettinger
Tim Peters
Armin Rigo
Fred Drake
Walter Dörwald
Anthony Baxter
Martin v. Löwis
Jason Tishler
Hye-Shik Chang
Neal Norwitz
Nicholas Bastin
Jack Jansen
Jim Fulton
Brett Cannon
Marc-André Lemburg
Thomas Heller
Skip Montanaro
Michael W. Hudson
Jeremy Hylton
Andrew MacIntyre
Alex Martelli
Barry Warsaw
Guido van Rossum
Christian Tismer
Mark Hammond
Gustavo Niemeyer