[pepijndevos]

Say I wrote my own CPU (which I did), which of those tiny C compilers would be easiest to retarget?

My CPU is very small, (~300 LUT4 on an FPGA using Yosys), but has a very minimal ISA. It's mostly an accumulator machine with a stack pointer.

[nils-m-holm]

SubC is very easy to retarget, especially the book version. It is not a full C compiler, though.

http://t3x.org/subc/

[Rietty]

I'm interested in what you mean by "wrote my own CPU". Could you elaborate please?

[pepijndevos]

https://github.com/pepijndevos/seqpu/blob/master/cpu.vhd