error[E0425]: cannot find value `foo` in this scope
  --> $DIR/dont-match-error-ty-with-calller-supplied-obligation-issue-121941.rs:2:5
   |
LL |     foo == 2;
   |     ^^^ not found in this scope

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0425`.