error[E0599]: no method named `f9` found for type `usize` in the current scope
  --> $DIR/issue-7575.rs:74:18
   |
LL |     u.f8(42) + u.f9(342) + m.fff(42)
   |                  ^^
   |
   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
   = help: try with `usize::f9`
note: candidate #1 is defined in the trait `CtxtFn`
  --> $DIR/issue-7575.rs:16:5
   |
LL |     fn f9(_: usize) -> usize;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
   = help: to disambiguate the method call, write `CtxtFn::f9(u, 342)` instead
note: candidate #2 is defined in the trait `OtherTrait`
  --> $DIR/issue-7575.rs:20:5
   |
LL |     fn f9(_: usize) -> usize;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
   = help: to disambiguate the method call, write `OtherTrait::f9(u, 342)` instead
note: candidate #3 is defined in the trait `UnusedTrait`
  --> $DIR/issue-7575.rs:29:5
   |
LL |     fn f9(_: usize) -> usize;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
   = help: to disambiguate the method call, write `UnusedTrait::f9(u, 342)` instead
   = help: items from traits can only be used if the trait is implemented and in scope
   = note: the following traits define an item `f9`, perhaps you need to implement one of them:
           candidate #1: `CtxtFn`
           candidate #2: `OtherTrait`
           candidate #3: `UnusedTrait`

error[E0599]: no method named `fff` found for type `Myisize` in the current scope
  --> $DIR/issue-7575.rs:74:30
   |
LL | struct Myisize(isize);
   | ---------------------- method `fff` not found for this
...
LL |     u.f8(42) + u.f9(342) + m.fff(42)
   |                              ^^^
   |
   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
   = help: try with `Myisize::fff`
note: candidate #1 is defined in an impl for the type `Myisize`
  --> $DIR/issue-7575.rs:51:5
   |
LL |     fn fff(i: isize) -> isize {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^

error[E0599]: no method named `is_str` found for type `T` in the current scope
  --> $DIR/issue-7575.rs:82:7
   |
LL |     t.is_str()
   |       ^^^^^^
   |
   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
   = help: try with `T::is_str`
note: candidate #1 is defined in the trait `ManyImplTrait`
  --> $DIR/issue-7575.rs:57:5
   |
LL |     fn is_str() -> bool {
   |     ^^^^^^^^^^^^^^^^^^^
   = help: to disambiguate the method call, write `ManyImplTrait::is_str(t)` instead
   = help: items from traits can only be used if the trait is implemented and in scope
   = note: the following trait defines an item `is_str`, perhaps you need to implement it:
           candidate #1: `ManyImplTrait`

error: aborting due to 3 previous errors

For more information about this error, try `rustc --explain E0599`.