While benchmarking the impact of Zig removing inlines from their
standard cryptography library, my
naive initial approach compared the changes from the perspective of the Zig
project as a whole, not just the standard library itself. In reality, this
meant every time I modified a Zig crypto implementation while experimenting,
even just to call std.debug.print, I was rebuilding the entire project from
source.
The Zig build system feels powerful and I’m planning out a new project to coat myself in all the grimy details1. In the meantime, I got started with Loris Cro’s excellent Zig Build System Basics video, and the existing documentation. I followed the Zig wiki’s instructions for building from source on both mac and linux.
But, of course, there’s a flag for that:
$ zig build --help
Usage: zig build [steps] [options]
...
Advanced Options:
...
--zig-lib-dir [arg] Override path to Zig lib directory
...
We can input the path of the lib directory containing an instantiation of the
Zig standard library and zig build will compile without extra steps or
linking. Now instead of feeling stuck at the bird’s eye view of the entire
Zig source, it’s much easier to quickly compare and contrast the small nudges
and curiosities.
Just call:
zig build --zig-lib-dir ../zig-master/lib
Those familiar with the ziglang codebase may
note that the directory for the standard library isn’t lib/, it’s lib/std/.
This means that --zig-lib-dir allows us specify a lot more than just the
standard library for injection, we’re just scratching the surface here2.
Benchmarking changes is much smoother now. I simply point my script to the
appropriate git worktree directory for each version and away we go!
