Compilation error using zig-bootstrap and latest master zig

[lalinsky]

Interesting, it’s hitting this problem I found earlier.

Nested error union

I have a strange need for function that returns Cancelable!T, where T could also be an error union. Even though the compiler recognizes the nested error union, I can’t return the T value. src/select.zig:203:29: error: expected type 'error{Canceled}!error{Foo}!i32', found 'error{Foo}!i32' return fut.getResult(); ~~~~~~~~~~~~~^~ src/select.zig:203:29: note: error union payload 'i32' cannot cast into error union payload 'error{Foo}!i32' src/select.zig:186:54: note: function …

Apparently something in the Zig standard library wanted to use std.Io.Queue on elements that are error unions, from a function that also wants to return its own error set, but the compiler doesn’t like it.

Either std or the compiler needs to be fixed.