error[E0596]: cannot borrow `v` as mutable, as it is not declared as mutable
  --> $DIR/many-mutable-borrows.rs:2:9
   |
LL |     let v = Vec::new();
   |         ^ not mutable
LL |     v.push(0);
   |     --------- cannot borrow as mutable
LL |     v.push(0);
   |     --------- cannot borrow as mutable
LL |     v.push(0);
   |     --------- cannot borrow as mutable
LL |     v.push(0);
   |     --------- cannot borrow as mutable
LL |     v.push(0);
   |     --------- cannot borrow as mutable
LL |     v.push(0);
   |     --------- cannot borrow as mutable
LL |     v.push(0);
   |     --------- cannot borrow as mutable
LL |     v.push(0);
   |     --------- cannot borrow as mutable
LL |     v.push(0);
   |     --------- cannot borrow as mutable
   |
   = note: ...and 5 other attempted mutable borrows
help: consider changing this to be mutable
   |
LL |     let mut v = Vec::new();
   |         +++

error: aborting due to previous error

For more information about this error, try `rustc --explain E0596`.