Comment by actionfromafar

3 months ago

Just in case you aren't in the loop, but there are gcc and llvm based Amiga cross compilers.

GCC cross-compiling for the Amiga is available from https://franke.ms/git/bebbo/amiga-gcc for a standalone toolchain, and https://github.com/BartmanAbyss/vscode-amiga-debug for one that requires VSCode.

I'm not aware of any working LLVM solution? All I know is that LLVM supports MC680x0 as a backend, can spit out 68k-but-non-amiga-objects and some brave souls have trying to use vlink or mold to produce Amiga executables. Have you seen any working LLVM-based Amiga (680x0 in hunk format) cross-compilers in the wild?

Actually I wasn't able to do it also with Bebbo's GCC fork.

Never used Nim before so I might be doing something wrong though.

I wish retro Amiga had Rust support. I've briefly skimmed what would be necessary to do, based on the rust-mos (Rust for commodore-64 fork), but I'm too weak in LLVM internals to actually do it.

  • > Never used Nim before so I might be doing something wrong though.

    With Nim on weird targets you usually want:

    - OS target = any

    - Memory Management = ARC

    - malloc instead of default Nim allocator

    - turn off signal handler (if not POSIX)

    - disable threads (most of the time)

    Then look at how C is compiled and copy all compiler+linker flags to your Nim configuration. Here's an absolute minimal `config.nims` I used to compile Nim for C64 with LLVM-MOS[1] toolchain:

        import std/strutils
        
        --cc:clang
        --clang.exe:"mos-c64-clang"
        
        --os:any
        --cpu:avr
        --mm:arc
        
        --threads:off
        --define:usemalloc
        --define:noSignalHandler
        
        let args = [
          "-isystem $PWD/../mos-platform/c64/include",
          "-I$PWD/../mos-platform/c64/asminc",
          "-L$PWD/../mos-platform/c64/lib",
          "-mlto-zp=110",
          "-D__C64__",
        
          "-isystem $PWD/../mos-platform/commodore/include",
          "-I$PWD/../mos-platform/commodore/asminc",
          "-L$PWD/../mos-platform/commodore/lib",
          "-D__CBM__",
        
          "-isystem $PWD/../mos-platform/common/include",
          "-I$PWD/../mos-platform/common/asminc",
          "-L$PWD/../mos-platform/common/lib",
          "--target=mos",
          "-flto",
          "-Os",
          ].join(" ")
        
        switch("passC", args)
        switch("passL", args)
    

    Nim side was easy, because I have already compiled Nim to WASM at that point and the flags are similar. Hard part was figuring out the C compiler flags: e.g. cmake structure and why compiler complains about missing symbols, when they're not missing (answer: include/lib order is very important).

    [1] https://github.com/llvm-mos/llvm-mos