The Small Device C Compiler (SDCC), targeting 8-bit architectures
A minimalistic but complete standard Forth compiler in C
Scripts, Makefiles, tools helping to build TinyCC on Windows and wine.
C compiler and dev kit for the z80 with assembly language libraries.
Binary executable decompiler
multi-platform cross assembler for 6502/6510/65816 cpu
Eclipse C/C++ MinGW MSYS2
EMX compiler hosted on Win32
Implementations for the Revised Report language
Oberon family of languages to C translator for ARM, x64 and x86 archit
Mariko's GCC for the x68000
ATasm is a 6502 command-line cross-assembler.
Ada cross compiler and libraries for AVR µCs
A "Just Enough Language" compiler targeting the 6502/Z80/6809
Micro Programming Language - A Portable Language for Micro Computers
Homebrew toolchains for wii, gamecube, 3ds, ds, gba, gp32 and psp
Supports writing Ada software for Cortex-M3, M4F boards
A C Compiler/Editor for Retro 6809 Machines (Colour Computer/Dragon)
A kit for cross-platform & embedded development in modular languages.
C to Pascal converter to port math routines in Lazarus/Delphi.