* floating point differences between the build machine and the target. By far the most common
* endiannes - code assumes little median runs on big endian
There’s other more subtle issues that can crop up but those are the big two.
Not saying I agree though - those can happen anyway when you run on two different machines anyway.
In Rust we can expand what is possible at compile time without breaking existing code because we took a very careful approach only stabilizing what we are sure about. Some things will probably never be possible at compile time in Rust.
Zig is much more powerful but that also means they cannot take stuff away without breaking existing code and making comptime more restricted. So it is unlikely Zig will ever become like Rust in that regard, but that is ok - just different approaches.