error[E0381]: use of possibly uninitialized variable: `v`
  --> $DIR/borrowck-init-plus-equal.rs:3:9
   |
LL |     v = v + 1; //~ ERROR use of possibly uninitialized variable: `v`
   |         ^ use of possibly uninitialized `v`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0381`.