I want to step through aro_translate_c.zig in a debugger to see how it works.
I have a debug build of zig and debugging the clang-based translate-c with lldb works fine, but it doesn’t work for Aro translate-c (i.e. zig translate-c -fno-clang), because this is one of the components that is not compiled into the zig binary, but lazily built when you use it, see ship even more of the compiler in source form · Issue #19063 · ziglang/zig · GitHub
Thank you, with ZIG_DEBUG_CMD=1 it works, and I had to tell lldb to follow the child process (settings set target.process.follow-fork-mode child).
Running it directly also works, you just need to add the aro module to build it (e.g. ../build/stage3/bin/zig build-exe --dep aro -Maro-translate-c=../lib/compiler/aro_translate_c.zig -Maro=../lib/compiler/aro/aro.zig).