Re: Building on Win7 x64 for python2.6.4 x64 DLL load failed Error

Windows and the various Python versions are always ....err.... challenging.
In an embedded setup like this, if extensions are build with a different
version of Visual C then the python interpreter, it can cause DLL load
issues, which might be what we are seeing.

Few ideas:
* Can you look in the windows event log to see what DLL it is failing
loading?
* Can you verify which compiler was used to build that version of python
by opening up an interactive shell? Should be the first line, or
'sys.version'. Python 2.6's default compiler used VC 2008 (v.1500), which
sounds like what you are trying to build against, but maybe they used a
newer version to build Maya?
* Did you build the libpq.lib for linking, or was it part of a PostgreSQL
distribution? At one time, the PostgreSQL distribution renamed the
libpqdll.lib link library to the static version (libpq.lib). Not sure if
that is still the case, but it might possible you need to have the
libpq.dll placed in the location that the interpreter can find it if you
built against a PostgreSQL distribution.

-jason

On Thu, Nov 28, 2013 at 10:58 AM, Jack Straw <
jack(dot)straw(at)saddingtonbaynes(dot)com> wrote:

> It does smell like it but I cannot find the source of the smell. I'm
> definitely using x64 build tools, the Maya install is x64 and I have
> checked that the python is x64 (using "print("%x" % sys.maxsize,
> sys.maxsize > 2**32)").
>
> Do you have any experience with Dependancy Walker? A lot of the links
> reference it to find the missing dependencies but I have no idea what to do
> with the information.
>
> Jack
>
>
> On 28 November 2013 17:41, Daniele Varrazzo <daniele(dot)varrazzo(at)gmail(dot)com>wrote:
>
>> On Thu, Nov 28, 2013 at 5:26 PM, Jack Straw
>> <jack(dot)straw(at)saddingtonbaynes(dot)com> wrote:
>> > Hi,
>> >
>> > I am trying to build psycopg2 for a version of python that is packaged
>> with
>> > the 3D creation package Maya (version 2013). I can build and install
>> > psycopg2 to the python install but when load the module I get the
>> following
>> > error;
>> >
>> > # Error: ImportError: file C:\Program
>> > Files\Autodesk\Maya2013\Python\lib\site-packages\psycopg2\__init__.py
>> line
>> > 50: DLL load failed: %1 is not a valid Win32 application. #
>> >
>> > My build process is;
>> >
>> > Run the x64 VS9 build environment setup script
>> > Build the cextenstion, including the right libs and headers; "C:\Program
>> > Files\Autodesk\Maya2013\bin\mayapy.exe" setup.py build_ext -"IC:\Program
>> > Files\Autodesk\Maya2013\include\python2.6" -"LC:\Program
>> > Files\Autodesk\Maya2013\lib"
>> > Build the rest of the module
>> > Install
>>
>> Smells like a 32/64 bit mess-up between Maya, Python and the compiler.
>>
>> Googling "python DLL load failed: %1 is not a valid Win32 application"
>> yields lots of result, for example
>>
>>
>> http://stackoverflow.com/questions/4676433/solving-dll-load-failed-1-is-not-a-valid-win32-application-for-pygame
>>
>> Particularly interesting is this resource:
>>
>> http://www.lfd.uci.edu/~gohlke/pythonlibs/#psycopg
>>
>> offering alternative win builds of psycopg.
>>
>> -- Daniele
>>
>
>