Unreachable code

Built from the repository at commit a8614dc.

A statement that comes after one that never finishes, such as return, break, continue, or an if whose branches all return, can never run. The warning points at the first such statement in the block.

Why

Code that cannot run is almost always a mistake: a return written too early, or a statement meant to come before a break. Sisu warns where the source tells its reader something false, as it does for a let mut that never changes (ADR 0011).

Broken

fn main() {
    print(1)
    return
    print(2)
}

What sisu says

warning[W0001]: unreachable code
 --> W0001.sisu:4:5
  |
4 |     print(2)
  |     ^^^^^^^^

sisu: 1 warning
sisu: for more on a code, run `sisu explain <code>`: W0001

Fixed

fn main() {
    print(1)
    print(2)
}