As of python 2.7.1 configured with "--enable-ipv6 --enable-unicode --with-system-expat --with-system-ffi --with-signal-module --with-threads --with-wctype-functions --enable-shared":

Please #include <wctype.h> in Objects/unicodetype_db.h and Objects/unicodectype.c

compilation produces the warnings:

In file included from Objects/unicodectype.c:34:0:
Objects/unicodetype_db.h: In function '_PyUnicodeUCS2_IsWhitespace':
Objects/unicodetype_db.h:3277:5: warning: implicit declaration of function 'iswspace'
Objects/unicodectype.c: In function '_PyUnicodeUCS2_IsLowercase':
Objects/unicodectype.c:192:5: warning: implicit declaration of function 'iswlower'
Objects/unicodectype.c: In function '_PyUnicodeUCS2_IsUppercase':
Objects/unicodectype.c:197:5: warning: implicit declaration of function 'iswupper'
Objects/unicodectype.c: In function '_PyUnicodeUCS2_ToLowercase':
Objects/unicodectype.c:202:5: warning: implicit declaration of function 'towlower'
Objects/unicodectype.c:202:12: warning: incompatible implicit declaration of built-in function 'towlower'
Objects/unicodectype.c: In function '_PyUnicodeUCS2_ToUppercase':
Objects/unicodectype.c:207:5: warning: implicit declaration of function 'towupper'
Objects/unicodectype.c:207:12: warning: incompatible implicit declaration of built-in function 'towupper'
Objects/unicodectype.c: In function '_PyUnicodeUCS2_IsAlpha':
Objects/unicodectype.c:212:5: warning: implicit declaration of function 'iswalpha'

Дилян Палаузов wrote:
> 
> New submission from Дилян Палаузов <dilyan.palauzov@aegee.org>:
> 
> As of python 2.7.1 configured with "--enable-ipv6 --enable-unicode --with-system-expat --with-system-ffi --with-signal-module --with-threads --with-wctype-functions --enable-shared":
> 
> Please #include <wctype.h> in Objects/unicodetype_db.h and Objects/unicodectype.c
> 
> compilation produces the warnings:
> 
> In file included from Objects/unicodectype.c:34:0:
> Objects/unicodetype_db.h: In function '_PyUnicodeUCS2_IsWhitespace':
> Objects/unicodetype_db.h:3277:5: warning: implicit declaration of function 'iswspace'
> Objects/unicodectype.c: In function '_PyUnicodeUCS2_IsLowercase':
> Objects/unicodectype.c:192:5: warning: implicit declaration of function 'iswlower'
> Objects/unicodectype.c: In function '_PyUnicodeUCS2_IsUppercase':
> Objects/unicodectype.c:197:5: warning: implicit declaration of function 'iswupper'
> Objects/unicodectype.c: In function '_PyUnicodeUCS2_ToLowercase':
> Objects/unicodectype.c:202:5: warning: implicit declaration of function 'towlower'
> Objects/unicodectype.c:202:12: warning: incompatible implicit declaration of built-in function 'towlower'
> Objects/unicodectype.c: In function '_PyUnicodeUCS2_ToUppercase':
> Objects/unicodectype.c:207:5: warning: implicit declaration of function 'towupper'
> Objects/unicodectype.c:207:12: warning: incompatible implicit declaration of built-in function 'towupper'
> Objects/unicodectype.c: In function '_PyUnicodeUCS2_IsAlpha':
> Objects/unicodectype.c:212:5: warning: implicit declaration of function 'iswalpha'

--with-wctype-functions will only work if you have configured Python
to use the Unicode variant which is used by wchar_t on your platform.

Given the warnings you are seeing, this appears to be UCS4,
so you have to add --enable-unicode=ucs4 to your configure line.

Please note that support for wctype functions is not being
actively supported in Python anymore. I'd suggest you remove
the --with-wctype-functions option altogether.

--with-wctype-functions was removed in 3.2 (see issue9210, r84752)

Python 2.7 fails even with --enable-unicode=ucs4:

$ ./configure --with-wctype-functions --enable-unicode=ucs4
$ make 
...
In file included from Objects/unicodectype.c:34:0:
Objects/unicodetype_db.h: In function '_PyUnicodeUCS4_IsWhitespace':
Objects/unicodetype_db.h:3277:5: warning: implicit declaration of function 'iswspace' [-Wimplicit-function-declaration]
Objects/unicodectype.c: In function '_PyUnicodeUCS4_IsLowercase':
Objects/unicodectype.c:192:5: warning: implicit declaration of function 'iswlower' [-Wimplicit-function-declaration]
Objects/unicodectype.c: In function '_PyUnicodeUCS4_IsUppercase':
Objects/unicodectype.c:197:5: warning: implicit declaration of function 'iswupper' [-Wimplicit-function-declaration]
Objects/unicodectype.c: In function '_PyUnicodeUCS4_ToLowercase':
Objects/unicodectype.c:202:5: warning: implicit declaration of function 'towlower' [-Wimplicit-function-declaration]
Objects/unicodectype.c:202:12: warning: incompatible implicit declaration of built-in function 'towlower' [enabled by default]
Objects/unicodectype.c: In function '_PyUnicodeUCS4_ToUppercase':
Objects/unicodectype.c:207:5: warning: implicit declaration of function 'towupper' [-Wimplicit-function-declaration]
Objects/unicodectype.c:207:12: warning: incompatible implicit declaration of built-in function 'towupper' [enabled by default]
Objects/unicodectype.c: In function '_PyUnicodeUCS4_IsAlpha':
Objects/unicodectype.c:212:5: warning: implicit declaration of function 'iswalpha' [-Wimplicit-function-declaration]

I have attached a patch that checks for wctype.h and includes it for WANT_WCTYPE_FUNCTIONS.

In Python 3.3+ functions like iswlower() are no longer used for Py_UNICODE_ISLOWER etc. And Python 2.7 is no longer supported.