[Spex_guy]

> What kind of tests are these "behavior test"?

Snippets of zig code that use language features and then make sure those features did the right thing. You can find them here: https://github.com/ziglang/zig/tree/master/test/behavior

> Is that a list of compilation targets?

Mostly. Pedantically, it's a list of code generation backends, each of which may have multiple compilation targets. So for example the LLVM backend can target many architectures. The ones that are architecture specific are currently debug-only and cannot do optimization.

> If not all behavior tests pass, does that not mean that the compiler fails to compile programs correctly?

Some tests are not passing because they cause an incorrect compile error, others compile but have incorrect behavior (miscompilation). Don't use Zig in production yet ;)

(edit: fix formatting)

[kristoff_it]

To add to what Spex said: also some of those tests check language features that the compiler code doesn't exercise, like async/await. This means that the compiler is able to build itself, but is not able to build every possible valid Zig program. We're getting there though :^)