error[E0009]: cannot bind by-move and by-ref in the same pattern
  --> $DIR/for.rs:6:13
   |
LL |     for (n, mut m) in &tups {
   |          -  ^^^^^ by-move pattern here
   |          |
   |          by-ref pattern here

error[E0507]: cannot move out of a shared reference
  --> $DIR/for.rs:6:23
   |
LL |     for (n, mut m) in &tups {
   |             -----     ^^^^^
   |             |
   |             data moved here
   |             move occurs because `m` has type `Foo`, which does not implement the `Copy` trait

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0009, E0507.
For more information about an error, try `rustc --explain E0009`.