Using x64 dll in x86 application

Question

I have a DLL that needs to operate large ammounts of memory and must be x64 to do that, but the application, which calls it is x86 and can not be converted to x64. COM is already used for interaction between application and the dll.

Is it possible to use surrogate process for that purpose?

I know that it is possible to do such a thing in the opposite case (run x86 COM library in x64 application), will there be any difference?

Answer 1

Yea, you can, and there should be no differences as COM handles everything for you.

On 64-bit Windows, an out-of-process 32-bit COM server can communicate with a 64-bit client, and an out-of-process 64-bit COM server can communicate with a 32-bit client.

http://msdn.microsoft.com/en-us/library/aa384231(VS.85).aspx