[Python-Dev] wchar_t (was Adventures with x64, VS7 and VS8) on Windows (original) (raw)

Mark Hammond mhammond at skippinet.com.au
Mon May 21 13:46:53 CEST 2007

Kristján Valur Jónsson quoting me:

> hrm - as above, I'm more concerned with the definition of > WCHAR - which > means my problem is related more to the Platform SDK version rather > than the > compiler. This is unfortunate - on one hand we do consider > 'platform=Windows API', and WCHAR is very much an API concept. I'll > need to > dig some more into this, but at least I know I'm not > wasting my time :)

Mark, your problem may be related to a setting in the "c/c++ -> language" tab in the settings, where "treat wchart as a builtin type" default has changed. I recommend that we do treat it as a builtin, but the VS2003 default was "no" and the 2005 is "yes". Could this be contributing to your problem?

Thanks for the suggestion and for introducing me to that option - but it made no difference. I'm guessing its related to C++ - code such as the following:

static PyObject *TestIBuild() { // obviously nonsense - the point is to test if it compiles. WCHAR *wval = PyUnicode_AS_UNICODE(Py_None); return PyUnicode_FromUnicode(wval, wcslen(wval)); }

works everywhere - except in a pywin32 .cpp file built on x64:) That code results in:

win32/src/win32apimodule.cpp(81) : error C2440: 'initializing' : cannot convert from 'Py_UNICODE *' to 'WCHAR *' Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast win32/src/win32apimodule.cpp(82) : error C2664: 'PyUnicodeUCS2_FromUnicode' : cannot convert parameter 1 from 'WCHAR *' to 'const PyUNICODE *' Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast

Unfortunately I don't have pywin32 building under vc8 on x32, but expect it to happen there too. pywin32 uses distutils, but I inspected the options passed and can't find anything to make a difference. /Zc:wchar_t and/or /Zc:wchar_t- seem to be the command-line settings for this flag and it also makes no difference. I'm out of time to confirm is is simply "c++ with vs8", but did confirm that the patch below appears to solve the problem, and given Martin's previous +1, I decided to stop there. I failed in a quick attempt at replacing the literal 2 with something involving sizeof. Does this look reasonable?

Cheers,

Mark

Index: pyconfig.h

--- pyconfig.h (revision 55487) +++ pyconfig.h (working copy) @@ -492,10 +492,10 @@ #define Py_USING_UNICODE

/* Define as the integral type used for Unicode representation. */ -#define PY_UNICODE_TYPE unsigned short +#define PY_UNICODE_TYPE wchar_t

/* Define as the size of the unicode type. */ -#define Py_UNICODE_SIZE SIZEOF_SHORT +#define Py_UNICODE_SIZE 2

/* Define if you have a useable wchar_t type defined in wchar.h; useable means wchar_t must be 16-bit unsigned type. (see

-------------- next part -------------- A non-text attachment was scrubbed... Name: winmail.dat Type: application/ms-tnef Size: 3260 bytes Desc: not available Url : http://mail.python.org/pipermail/python-dev/attachments/20070521/12f28bf0/attachment.bin

More information about the Python-Dev mailing list