error[E0428]: the name `Foo` is defined multiple times
  --> $DIR/issue-106072.rs:5:1
   |
LL | struct Foo;
   | ----------- previous definition of the type `Foo` here
LL | trait Foo {}
   | ^^^^^^^^^ `Foo` redefined here
   |
   = note: `Foo` must be defined only once in the type namespace of this module

error[E0277]: the size for values of type `(dyn Foo + 'static)` cannot be known at compilation time
  --> $DIR/issue-106072.rs:1:10
   |
LL | #[derive(Clone)]
   |          ^^^^^ doesn't have a size known at compile-time
   |
   = help: the trait `Sized` is not implemented for `(dyn Foo + 'static)`
note: required by a bound in `Clone`
  --> $SRC_DIR/core/src/clone.rs:LL:COL
   = note: this error originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0746]: return type cannot have an unboxed trait object
  --> $DIR/issue-106072.rs:1:10
   |
LL | #[derive(Clone)]
   |          ^^^^^ doesn't have a size known at compile-time
   |
   = note: this error originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0782]: trait objects must include the `dyn` keyword
  --> $DIR/issue-106072.rs:1:10
   |
LL | #[derive(Clone)]
   |          ^^^^^
   |
   = note: this error originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)

error: aborting due to 4 previous errors

Some errors have detailed explanations: E0277, E0428, E0746, E0782.
For more information about an error, try `rustc --explain E0277`.