Code like this is fixed now:
```
fn foo(p: [u8, ..4]) {
match p {
[a, b, c, d] => {}
};
}
```
Invalid constructors are not reported as errors yet:
```
fn foo(p: [u8, ..4]) {
match p {
[_, _, _] => {} // this should be error
[_, _, _, _, _, .._] => {} // and this
_ => {}
}
}
```
Issue #8311 is partially fixed by this commit. Fixed-length arrays in
let statement are not yet allowed:
```
let [a, b, c] = [1, 2, 3]; // still fails
```
