Mailman 3 October 2002 - Python-Dev

"conflicting types" in python CVS build
by Alex Coventry Oct. 27, 2002

Oct. 27, 2002

hi. i built a fresh checkout of python from CVS, and got this error: Parser/pgenmain.c:169: conflicting types for PyOS_Readline' Include/pythonrun.h:116: previous declaration of PyOS_Readline' make: *** [Parser/pgenmain.o] Error 1 cvs annoate says the latest prototype for PyOS_Readline is in pythonrun.h. Commenting that line out results in a complete build that passes the test suite. hope this helps. alex.

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Re: Memory size overflows
by Gerald S. Williams Oct. 25, 2002

Oct. 25, 2002

I didn't find any way to improve the actual overflow check, although if you entirely replace the "fast path" check with checks involving unsigned masking, you get some performance improvement. For a wide variety of input patterns, I get about an 18% speedup versus the core long multiply code, when modified as shown below: #define UL_LO_HI_BIT (((unsigned long)1) << (sizeof(unsigned long) * 4U)) #define UL_LO_MASK ((UL_LO_HI_BIT) - 1) #define UL_HI_MASK (~(UL_LO_MASK)) #define UL_HI_LO_BIT (((unsigned long)1) << ((sizeof(unsigned long) * 4U)-1)) #define UL_OVERFLOW_IMPOSSIBLE_MASK ((UL_HI_LO_BIT) - 1) #define UL_OVERFLOW_POSSIBLE_MASK (~(UL_OVERFLOW_IMPOSSIBLE_MASK)) long core_int_mul(long a, long b) { long longprod = a * b; unsigned long ma = a & UL_HI_MASK; if (ma == ((a < 0) ? UL_HI_MASK : 0)) { unsigned long mb = b & UL_OVERFLOW_POSSIBLE_MASK; if (mb == ((b < 0) ? UL_OVERFLOW_POSSIBLE_MASK : 0)) { return longprod; } } { double doubleprod = (double)a * (double)b; double doubled_longprod = (double)longprod; double diff = doubled_longprod - doubleprod; double absdiff = (diff >= 0.0) ? diff : -diff; double absprod = (doubleprod >= 0.0) ? doubleprod : -doubleprod; /* absdiff/absprod <= 1/32 iff 32 * absdiff <= absprod -- 5 good bits is "close enough" */ if (32.0 * absdiff <= absprod) { return longprod; } else { SIGNAL_AN_ERROR; } } } This version suffers no apparent degradation versus the existing implementation when fed sets of multiplicands evenly distributed over range(-sys.maxint, sys.maxint), and almost always shows an improvement. Shall I submit a patch? -Jerry

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pyconfig.h and exec-prefix
by David Abrahams Oct. 24, 2002

Oct. 24, 2002

This issue came up on the c++-sig. I'm not qualified to answer any of the questions at the bottom, and hoped that this forum could be of some help. From: "Paul F. Kunz" <Paul_Kunz(a)SLAC.Stanford.EDU> Subject: Re: [C++-sig] Boost V1 build on Solaris To: c++-sig(a)python.org Date: Wed, 23 Oct 2002 17:36:58 -0700 Reply-To: c++-sig(a)python.org One final question, which is not specific to boost::python but general question on building Python modules. What my Solaris administrators have done is to configure Python with > ./configure --prefix=/afs/.slac.stanford.edu/package/python/common/2.0 --exec-prefix=/afs/.slac.stanford.edu/package/python/sun4x_55/2.0 They also did a build fron Linux with the appropriate `exec-prefix'. What apparently this has done is to put all but one of the Python include files in the directory `common/2.0/include'. But Python.h includes `config.h' or `pyconfig.h' (depending on the version) which gets installed in `sun4x_55/2.0/include'. This is appropriate since this file is machine/OS dependent. Now the problem is that boost::python, and other packages, gives you one variable, like PYTHON_INCLUDES, for its build. When it is set to find `Python.h' it will not find `pyconfig.h'. What is the best way to handle this situation? Is it a bug in Python's configure script? Bug in boost::python and others? Or am I missing something obvious? -- David Abrahams dave(a)boost-consulting.com * http://www.boost-consulting.com Building C/C++ Extensions for Python: Dec 9-11, Austin, TX http://www.enthought.com/training/building_extensions.html

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src/Mac/Tools/IDE/PyFontify.py
by Christopher Armstrong Oct. 24, 2002

Oct. 24, 2002

Hi! Python2.3 contains, inside the src/Mac/Tools/IDE/ directory a perfectly portable module called "PyFontify". Can this be added to the Python standard library somewhere under site-packages/? Twisted Matrix Labs distributes it with Twisted manually (with the copyright intact, of course), but this isn't very nice. -- Christopher Armstrong << radix(a)twistedmatrix.com >> http://twistedmatrix.com/users/radix.twistd/

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Re: Moving to Unicode 3.2 ([Python-checkins] python/dist/src/Objects unicodectype.c,2.11,2.12 unicodetype_db.h,1.4,1.5)
by M.-A. Lemburg Oct. 24, 2002

Oct. 24, 2002

loewis(a)users.sourceforge.net wrote: > Update of /cvsroot/python/python/dist/src/Objects > In directory usw-pr-cvs1:/tmp/cvs-serv10274/Objects > > Modified Files: > unicodectype.c unicodetype_db.h > Log Message: > Update to Unicode 3.2 database. I haven't seen any messages about this on python-dev. Did I miss something ? The switch from Unicode 3.0 is a big one since 3.2 introduces non-BMP character points for the first time. I also don't think that it is a good idea to ship the Unicode 3.2 database while the code behaves as defined in Unicode 3.0. And last not least, I'd like to be asked before you make such changes. Thanks, -- Marc-Andre Lemburg CEO eGenix.com Software GmbH _______________________________________________________________________ eGenix.com -- Makers of the Python mx Extensions: mxDateTime,mxODBC,... Python Consulting: http://www.egenix.com/ Python Software: http://www.egenix.com/files/python/

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OT: Pickling article
by Patrick K. O'Brien Oct. 23, 2002

Oct. 23, 2002

I recently finished an article for IBM's developerWorks website on Python Persistence Management. I basically cover quite a bit of material on pickling/unpickling. I'm looking for a couple of pickling experts to critique the article before it gets published. If you'd like to do so, please contact me offlist at pobrien(a)orbtech.com. Thanks. -- Patrick K. O'Brien Orbtech http://www.orbtech.com/web/pobrien ----------------------------------------------- "Your source for Python programming expertise." -----------------------------------------------

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tamper-evident logs
by Bryan L. Fordham Oct. 23, 2002

Oct. 23, 2002

here's a question for y'all: I've written a simple http proxy that logs the domains visited. The idea is that it keeps a list of the unique domains for each day. No problem. The problem is that I want it to be obvious if someone has deleted something from the logs. This is a little bit o' software meant to run on the user's box. It does not have to be impossible to tamper with it, nor do I need to be able to say what was removed; just "hey, someone futzed with the log!" Any ideas would be greatly appreciated. --B

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textwrap and unicode
by Greg Ward Oct. 23, 2002

Oct. 23, 2002

Well, my ignorance of Unicode has finally bitten me -- someone filed a bug (#622831) against textwrap.py because it crashes when it attempts to wrap a Unicode string. Here are the problems that I am aware of: * textwrap assumes "whitespace" means "the characters in string.whitespace" * textwrap assumes "lowercase letter" means "the characters in string.lowercase" (heck, this only works in English) Can someone tell me what the proper way to do this is? Or just point me at the relevant documentation? I've scoured the online docs and *Python Essential Reference*, and I know more about the codes and unicodedata modules than I did before. But I still don't know how to replace all whitespace with space, or detect words that end with a lowercase letter. Thanks -- Greg -- Greg Ward <gward(a)python.net> http://www.gerg.ca/ I brought my BOWLING BALL -- and some DRUGS!!

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Precompiled headers
by Jack Jansen Oct. 23, 2002

Oct. 23, 2002

Gcc on MacOSX has the ability to use precompiled headers, and I was toying with the idea of giving this a try for Python.h. Has anyone tried this, and is it worth the hassle? Also, are precompiled headers an Apple addition to gcc, or are they available on all platforms? I'm interested in trying this because when I started using precompiled headers for MacPython with the CodeWarrior compiler the build time for a complete Python tree want down by about 70%, so that's definitely worth a little effort... -- - Jack Jansen <Jack.Jansen(a)oratrix.com> http://www.cwi.nl/~jack - - If I can't dance I don't want to be part of your revolution -- Emma Goldman -

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pymalloc.supp (a valgrind suppressions file)
by Zooko Oct. 22, 2002

Oct. 22, 2002

# add the cmdline arg `--suppressions=thisfile' when invoking valgrind { PyObject_Free does tricky inside-a-page peeking, but it's really okay. Cond fun:PyObject_Free } { PyObject_Free does tricky inside-a-page peeking, but it's really okay. Value4 fun:PyObject_Free } { PyObject_Free does tricky inside-a-page peeking, but it's really okay. Addr4 fun:PyObject_Free } { PyObject_Realloc does tricky inside-a-page peeking, but it's really okay. Cond fun:PyObject_Realloc } { PyObject_Realloc does tricky inside-a-page peeking, but it's really okay. Value4 fun:PyObject_Realloc } { PyObject_Realloc does tricky inside-a-page peeking, but it's really okay. Addr4 fun:PyObject_Realloc }

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