[vibrolax]

And I have to disagree with one of your statements a little bit:

"The classic core Windows libraries and interfaces like GDI are plain old C."

__cdecl: this is the native C calling convention Calling function pops the arguments from the stack.

__stdcall: this is the standard Win32 library interface Called function pops its own arguments from the stack.

Calling conventions explained here: http://msdn.microsoft.com/en-us/library/k2b2ssfy.aspx