cross-compilation

Fast cross-compilation and cross-debugging are the main targets for user-mode emulation.

The operating system and most applications were written in the language Bliss-11, which required cross-compilation from a PDP-10.

This can be done via compilation on another system capable of building binaries for the intended target (possibly by cross-compilation).

It also has built-in support for cross-compilation of programs and extensions, which allows it to be used on various embedded platforms.

Delphi supports rapid native cross-compilation.

If Apple (for some reason) were to switch away from LLVM and this cross-compilation wasn't available, then what?

CMake can handle in-place and out-of-place builds, enabling several builds from the same source tree, and cross-compilation.

Unity supports several platforms, including the iPhone and the Wii, and comes with its own built-in Mono cross-compilation environment.

Frankly, the architecture divide is not that big a deal if M$ puts in the necessary effort in order to ensure that cross-compilation is not a pain.

Since debugging and testing may also require more resources than are available on an embedded system, cross-compilation can be less involved and less prone to errors than native compilation.

The GNU Compiler Collection (GCC) uses several intermediate languages internally to simplify portability and cross-compilation.

Accordingly almost all development now is based on cross-compilation from personal computers and download to the controller board through a serial-like interface, usually appearing to the host as a USB device.

But so, when one wants to build for an embedded target (cross-compilation), most of the detected parameters are incorrect (i.e. host configuration is not the same as the embedded target configuration).

There are a lot of hoops to jump through right now to set up iPhone cross-compilation for Mono, but de Icaza says that developers who want to start now can use Unity, a third-party commercial programming framework for 3D game development that is built on Mono.