error[E0369]: cannot add `{integer}` to `N`
  --> $DIR/issue-97677.rs:4:7
   |
LL |     n + 10
   |     - ^ -- {integer}
   |     |
   |     N
   |
help: consider restricting type parameter `N`
   |
LL | fn add_ten<N: std::ops::Add<i32, Output = N>>(n: N) -> N {
   |             ++++++++++++++++++++++++++++++++

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0369`.