This is a close cousin of “unreachable block” (E074): Turf found an if (or similar branch point) sitting inside code that’s already dead, so the branch itself – along with every path it could lead to – can never run either.
It almost always shows up alongside E074, on the same piece of dead code:
fn pick(x: int): int { while true { return 1; } if x > 0 { // dead branch -- everything after the loop is unreachable return 2; } return 3;}Because while true never exits any way other than its own return, nothing after the loop – including the if x > 0 check – is ever reached. Turf reports the unreachable block itself (E074) and, separately, that the branch inside it is dead (E075), since a conditional that can never be evaluated is worth calling out on its own.
The fix is the same as for E074: either make the loop exit somewhere (a break, or a condition that isn’t a literal true), or delete the code after it if it was never meant to run.
Run turf --explain E075 in a terminal to read this again.