Building Python with VC8 on x64 Vista

[danfike]

Hi all,

So I'm working on a C++ application that will eventually embed or
extend Python using Boost.Python, but I first need to get Python
compiled correctly for my platform. I've got a Windows Vista 64-bit
machine with a Core 2 processor, and I'm compiling with a VC8.

I downloaded the Python 2.5.1 source from python.org, and I opened the
Visual Studio solution file that was in the PCbuild8 directory. I
created a new x64 platform and managed to successfully compile the
'pythoncore' and 'python' projects (both in Debug and Release
configurations), resulting in working executables. (Aside: When
launched, the python console says "Python 2.5.1 [MSC v.1400 64 bit
(AMD64)] on win32" up top. Does that seem right?)

So, this program I'm writing with Boost.Python (that worked correctly
on x86 with home-built libraries) won't compile with these x64
libraries. I keep getting 'unresolved external symbols.' But, I'm
certain I'm linking in the library correctly. Here's a snippet from
the output (with /verbose:lib) when compiling:

1>Searching libraries
1 <snip>
1 Searching ..\..\..\3rdParty\boost_1_34_0\lib_x64\libboost_py thon-
vc80-mt-gy-1_34.lib:
1 <snip>
1 Searching ..\..\..\3rdParty\Python25\libs_x64\python25_d.lib :
1>Finished searching libraries
1>py_dyn_test.obj : error LNK2001: unresolved external symbol
_Py_NoneStruct
1>vector_py.obj : error LNK2001: unresolved external symbol
_Py_NoneStruct
1>volume_py.obj : error LNK2001: unresolved external symbol
_Py_NoneStruct
1>py_dyn_test.obj : error LNK2001: unresolved external symbol
_Py_RefTotal
1>vector_py.obj : error LNK2001: unresolved external symbol
_Py_RefTotal
1>volume_py.obj : error LNK2001: unresolved external symbol
_Py_RefTotal
1>volume_py.obj : error LNK2001: unresolved external symbol
PyExc_IndexError

If I switch to the Release configuration, I see fewer errors:

1>py_dyn_test.obj : error LNK2001: unresolved external symbol
_Py_NoneStruct
1>volume_py.obj : error LNK2001: unresolved external symbol
PyExc_IndexError

Note that none of my own code is Debug-specific. Also, the code in my
files is correct, because (as stated above), it worked fine for x86.

Though I don't know how useful it is, I did open the python libraries
in wordpad, and though most of the file wasn't legible, I did find
strings "Py_NoneStruct," "Py_RefTotal," and "PyExc_IndexError."
I suspect that I set up my "x64" platform configuration incorrectly,
or missed something. It's basically the same as the Win32
configuration, except with the /MACHINE:X64 flag instead of /
MACHINE:X86. One of the things I'm noticing just now, as I post this,
is that the preprocessor flag "WIN32" is still defined in the x64
configuration. Maybe if I change that to "WIN64," I'll have better
luck.

Any advice you have on what the "correct" way to do this is would be
appreciated.

-Dan

[danfike]

On Sep 20, 9:45 am, [e-mail] wrote:

Hi all,

So I'm working on a C++ application that will eventually embed or
extend Python using Boost.Python, but I first need to get Python
compiled correctly for my platform. I've got a Windows Vista 64-bit
machine with a Core 2 processor, and I'm compiling with a VC8.

I downloaded the Python 2.5.1 source from python.org, and I opened the
Visual Studio solution file that was in the PCbuild8 directory. I
created a new x64 platform and managed to successfully compile the
'pythoncore' and 'python' projects (both in Debug and Release
configurations), resulting in working executables. (Aside: When
launched, the python console says "Python 2.5.1 [MSC v.1400 64 bit
(AMD64)] on win32" up top. Does that seem right?)

So, this program I'm writing with Boost.Python (that worked correctly
on x86 with home-built libraries) won't compile with these x64
libraries. I keep getting 'unresolved external symbols.' But, I'm
certain I'm linking in the library correctly. Here's a snippet from
the output (with /verbose:lib) when compiling:

1>Searching libraries
1 <snip>
1 Searching ..\..\..\3rdParty\boost_1_34_0\lib_x64\libboost_py thon-
vc80-mt-gy-1_34.lib:
1 <snip>
1 Searching ..\..\..\3rdParty\Python25\libs_x64\python25_d.lib :
1>Finished searching libraries
1>py_dyn_test.obj : error LNK2001: unresolved external symbol
_Py_NoneStruct
1>vector_py.obj : error LNK2001: unresolved external symbol
_Py_NoneStruct
1>volume_py.obj : error LNK2001: unresolved external symbol
_Py_NoneStruct
1>py_dyn_test.obj : error LNK2001: unresolved external symbol
_Py_RefTotal
1>vector_py.obj : error LNK2001: unresolved external symbol
_Py_RefTotal
1>volume_py.obj : error LNK2001: unresolved external symbol
_Py_RefTotal
1>volume_py.obj : error LNK2001: unresolved external symbol
PyExc_IndexError

If I switch to the Release configuration, I see fewer errors:

1>py_dyn_test.obj : error LNK2001: unresolved external symbol
_Py_NoneStruct
1>volume_py.obj : error LNK2001: unresolved external symbol
PyExc_IndexError

Note that none of my own code is Debug-specific. Also, the code in my
files is correct, because (as stated above), it worked fine for x86.

Though I don't know how useful it is, I did open the python libraries
in wordpad, and though most of the file wasn't legible, I did find
strings "Py_NoneStruct," "Py_RefTotal," and "PyExc_IndexError."

I suspect that I set up my "x64" platform configuration incorrectly,
or missed something. It's basically the same as the Win32
configuration, except with the /MACHINE:X64 flag instead of /
MACHINE:X86. One of the things I'm noticing just now, as I post this,
is that the preprocessor flag "WIN32" is still defined in the x64
configuration. Maybe if I change that to "WIN64," I'll have better
luck.

Any advice you have on what the "correct" way to do this is would be
appreciated.

-Dan

I've tried re-building my libraries from the latest revision (58225),
using the solution in the PCbuild8 folder. I had no problems getting
the python25[_d].lib to compile, but I still get these symbol errors
when I try to link with the library.

-Dan

[Lawrence D'Oliveiro]

In message <11**********************@57g2000hsv.googlegroups. com>,
da*****@gmail.com wrote:

Though I don't know how useful it is, I did open the python libraries
in wordpad, and though most of the file wasn't legible, I did find
strings "Py_NoneStruct," "Py_RefTotal," and "PyExc_IndexError."

Do you have some equivalent of the "nm" command for dumping the symbols and
their definitions in the library?

[=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=]

1>py_dyn_test.obj : error LNK2001: unresolved external symbol

_Py_NoneStruct

Could it be that py_dyn_test.obj is a x86 (not AMD64) object
file? Run dumpbin.

Regards,
Martin

[danfike]

On Sep 22, 10:08 am, "Martin v. Löwis" <[e-mail]:

1>py_dyn_test.obj : error LNK2001: unresolved external symbol
_Py_NoneStruct

Could it be that py_dyn_test.obj is a x86 (not AMD64) object
file? Run dumpbin.

Hmm - I've never used dumpbin, but I think I like it.

It doesn't look like these are x86, though. See below:

D:\....\py_dyn_test\x64\Debug>dumpbin /HEADERS py_dyn_test.obj
Microsoft (R) COFF/PE Dumper Version 8.00.50727.762
Copyright (C) Microsoft Corporation. All rights reserved.
Dump of file py_dyn_test.obj

File Type: COFF OBJECT

FILE HEADER VALUES
8664 machine (x64)
....
D:\....\3rdParty\Python25\libs>dumpbin /HEADERS python25_d.lib
Microsoft (R) COFF/PE Dumper Version 8.00.50727.762
Copyright (C) Microsoft Corporation. All rights reserved.
Dump of file python25_d.lib

File Type: LIBRARY

FILE HEADER VALUES
8664 machine (x64)
3 number of sections
46F3CED2 time date stamp Fri Sep 21 09:01:54 2007
113 file pointer to symbol table
8 number of symbols
0 size of optional header
0 characteristics

<snip>

Version : 0
Machine : 8664 (x64)
TimeDateStamp: 46F3CED2 Fri Sep 21 09:01:54 2007
SizeOfData : 0000001E
DLL name : python25_d.dll
Symbol name : _Py_NoneStruct
Type : data
Name type : name
Hint : 900
Name : _Py_NoneStruct

<etc>

[=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=]

It doesn't look like these are x86, though.

Ok. Can you then check symbol lists also?: undefined
symbols in the object file, and defined symbols in the
library, wrt. PyExc_IndexError (say).

Regards,
Martin