error[E0308]: mismatched types
  --> $DIR/type-mismatch-same-crate-name.rs:21:20
   |
LL |         a::try_foo(foo2);
   |         ---------- ^^^^ expected `main::a::Foo`, found a different `main::a::Foo`
   |         |
   |         arguments to this function are incorrect
   |
note: two types coming from two different crates are different types even if they look the same
  --> $DIR/auxiliary/crate_a2.rs:1:1
   |
LL | pub struct Foo;
   | ^^^^^^^^^^^^^^ this is the found type `crate_a2::Foo`
   |
  ::: $DIR/auxiliary/crate_a1.rs:1:1
   |
LL | pub struct Foo;
   | ^^^^^^^^^^^^^^ this is the expected type `crate_a1::Foo`
   |
  ::: $DIR/type-mismatch-same-crate-name.rs:13:17
   |
LL |     let foo2 = {extern crate crate_a2 as a; a::Foo};
   |                 --------------------------- one type comes from crate `crate_a2` used here, which is renamed locally to `a`
...
LL |         extern crate crate_a1 as a;
   |         --------------------------- one type comes from crate `crate_a1` used here, which is renamed locally to `a`
note: function defined here
  --> $DIR/auxiliary/crate_a1.rs:10:8
   |
LL | pub fn try_foo(x: Foo){}
   |        ^^^^^^^

error[E0308]: mismatched types
  --> $DIR/type-mismatch-same-crate-name.rs:27:20
   |
LL |         a::try_bar(bar2);
   |         ---------- ^^^^ expected trait `main::a::Bar`, found a different trait `main::a::Bar`
   |         |
   |         arguments to this function are incorrect
   |
note: two types coming from two different crates are different types even if they look the same
  --> $DIR/auxiliary/crate_a2.rs:3:1
   |
LL | pub trait Bar {}
   | ^^^^^^^^^^^^^ this is the found trait `crate_a2::Bar`
   |
  ::: $DIR/auxiliary/crate_a1.rs:3:1
   |
LL | pub trait Bar {}
   | ^^^^^^^^^^^^^ this is the expected trait `crate_a1::Bar`
   |
  ::: $DIR/type-mismatch-same-crate-name.rs:13:17
   |
LL |     let foo2 = {extern crate crate_a2 as a; a::Foo};
   |                 --------------------------- one trait comes from crate `crate_a2` used here, which is renamed locally to `a`
...
LL |         extern crate crate_a1 as a;
   |         --------------------------- one trait comes from crate `crate_a1` used here, which is renamed locally to `a`
note: function defined here
  --> $DIR/auxiliary/crate_a1.rs:11:8
   |
LL | pub fn try_bar(x: Box<dyn Bar>){}
   |        ^^^^^^^

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0308`.