native 64-bit compilation on Win64 and .NET

[Dennis Landi]

Hello,

I have three questions:

1) I have been perusing the MSDN VC++ pages. Everything seems to be geared
towards .NET integration. Will MS continue support natively compiled code
or will they be pushing developers to do everything as "managed" C++?

2) Also, on 32-bit platforms we can call 32-bit unmanaged DLLS from managed
assemblies. On Win64 will a 64-bit .NET assembly be able to call an
unmanaged 64-bit DLL?

3) On the AMD64, thats supports the running of bot 32-bit and 64-bit code,
would we be able to call unmanaged 32-bit DLLs from a 64-bit .NET assembly?
(Sometimes its not practical/possible to recompile/port the 32-bit DLL).

Please let me know if there is a better forum for these questions...

Thanks.

-d

--

 

[Ronald Laeremans [MSFT]]

Hello,

I have three questions:

1) I have been perusing the MSDN VC++ pages. Everything seems to be geared
towards .NET integration. Will MS continue support natively compiled code
or will they be pushing developers to do everything as "managed" C++?

No, we fully supprt compiling native code.

2) Also, on 32-bit platforms we can call 32-bit unmanaged DLLS from managed
assemblies. On Win64 will a 64-bit .NET assembly be able to call an
unmanaged 64-bit DLL?

Yes, it will.

3) On the AMD64, thats supports the running of bot 32-bit and 64-bit code,
would we be able to call unmanaged 32-bit DLLs from a 64-bit .NET assembly?
(Sometimes its not practical/possible to recompile/port the 32-bit DLL).

No. You will have to use any of the supported IPC mechanisms like named
pipes, sockets, memory mapped files, COM. There is no type of thunk on
64-bit version of Windows that will allow 64-bit user mode code to call
32-bit user mode code in the same process.

Please let me know if there is a better forum for these questions...

Ronald Laeremans
Visual C++ team

 

[Dennis Landi]

No. You will have to use any of the supported IPC mechanisms like named
pipes, sockets, memory mapped files, COM. There is no type of thunk on
64-bit version of Windows that will allow 64-bit user mode code to call
32-bit user mode code in the same process.

Ronald, thanks for the response.

You mention COM as one way for 64-bit .NET assembly to communicate with a
32-bit DLL. So a 64-bit assembly could invoke a 32-bit out-of-process COM
object just like we would do it now on a 32-bit O.S.?

 

[Dennis Landi]

No. You will have to use any of the supported IPC mechanisms like named
pipes, sockets, memory mapped files, COM. There is no type of thunk on
64-bit version of Windows that will allow 64-bit user mode code to call
32-bit user mode code in the same process.

Ronald, thanks for the response.

You mention COM as one way for 64-bit .NET assembly to communicate with a
32-bit DLL. So a 64-bit assembly could invoke a 32-bit out-of-process COM
object just like we would do it now on a 32-bit O.S.?