[bsder]

> The zig community treats 'zig build' as "the compile step", ergo what "the compiler" gets ultimately is decided "at compile, er, zig build time". What the compiler gets, i.e., what zig build generates within the same user-facing process, is not deterministic.

I know of no build system that is completely deterministic unless you go through the process of very explicitly pinning things. Whereas practically every compiler is deterministic (gcc, for example, would rebuild itself 3 times and compare the last two to make sure they were byte identical). Perhaps there needs to be "zigmeson" (work out and generate dependencies) and "zigninja" (just call compiler on static resources) to set things apart, but it doesn't change the fact that "zig build" dispatches to a "build system" and "zig"/"zig cc" dispatches to a "compiler".

> Appeasing C interfaces will be moving to a zig build-time multi-step process involving zig's 'translate-c' whose output you then import into your zig file. You think anybody is going to treat that output differently than from what you'd get from doing this invisibly at comptime (which, btw, is what practically happens now)?

That's a completely different issue, but it illustrates the problem perfectly.

The problem is that @cImport() can be called from two different modules on the same file. What about if there are three? What about if they need different versions? What happens when a previous @cImport modifies how that file translates. How do you do link time optimization on that?

This is exactly why your compiler needs to run on static resources that have already been resolved. I'm fine with my build system calling a SAT solver to work out a Gordian Knot of dependencies. I am not fine with my compiler needing to do that resolution.