error[E0282]: type annotations needed for `Vec<_>`
  --> $DIR/cannot_infer_local_or_vec.rs:2:9
   |
LL |     let x = vec![];
   |         ^
   |
help: consider giving `x` an explicit type, where the placeholders `_` are specified
   |
LL |     let x: Vec<_> = vec![];
   |          ++++++++

error: aborting due to previous error

For more information about this error, try `rustc --explain E0282`.