error[E0506]: cannot assign to `vecvec` because it is borrowed --> $DIR/issue-27868.rs:24:9 | LL | vecvec[0] += { | ------ | | | _____`vecvec` is borrowed here | | LL | | vecvec = vec![]; | | ^^^^^^ `vecvec` is assigned to here but it was already borrowed LL | | LL | | 0 LL | | }; | |_____- borrow later used here error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0506`.