[jhallenworld]

Also: these old compilers ran on the target system. If all features are supported, the compiler might not fit into memory, and need many passes to work.

[OnlyMortal]

I know, from personal experience, that a lot of C64 games were written on PCs, cross-assembled and squirted to the C64 target.

This included graphics.

Circa 1989 so it was the backend of C64 development.

[pjmlp]

Also UNIX, VAX and CP/M systems, and not only in regards to C64.