1 files changed, 54 insertions, 0 deletions
diff --git a/src/test/ui/traits/bad-sized.stderr b/src/test/ui/traits/bad-sized.stderr
new file mode 100644
index 000000000..6f9113fff
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+++ b/src/test/ui/traits/bad-sized.stderr
@@ -0,0 +1,54 @@
+error[E0225]: only auto traits can be used as additional traits in a trait object
+  --> $DIR/bad-sized.rs:4:28
+   |
+LL |     let x: Vec<dyn Trait + Sized> = Vec::new();
+   |                    -----   ^^^^^ additional non-auto trait
+   |                    |
+   |                    first non-auto trait
+   |
+   = help: consider creating a new trait with all of these as supertraits and using that trait here instead: `trait NewTrait: Trait + Sized {}`
+   = note: auto-traits like `Send` and `Sync` are traits that have special properties; for more information on them, visit <https://doc.rust-lang.org/reference/special-types-and-traits.html#auto-traits>
+
+error[E0277]: the size for values of type `dyn Trait` cannot be known at compilation time
+  --> $DIR/bad-sized.rs:4:12
+   |
+LL |     let x: Vec<dyn Trait + Sized> = Vec::new();
+   |            ^^^^^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `dyn Trait`
+note: required by a bound in `Vec`
+  --> $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
+   |
+LL | pub struct Vec<T, #[unstable(feature = "allocator_api", issue = "32838")] A: Allocator = Global> {
+   |                ^ required by this bound in `Vec`
+
+error[E0277]: the size for values of type `dyn Trait` cannot be known at compilation time
+  --> $DIR/bad-sized.rs:4:37
+   |
+LL |     let x: Vec<dyn Trait + Sized> = Vec::new();
+   |                                     ^^^^^^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `dyn Trait`
+note: required by a bound in `Vec::<T>::new`
+  --> $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
+   |
+LL | impl<T> Vec<T> {
+   |      ^ required by this bound in `Vec::<T>::new`
+
+error[E0277]: the size for values of type `dyn Trait` cannot be known at compilation time
+  --> $DIR/bad-sized.rs:4:37
+   |
+LL |     let x: Vec<dyn Trait + Sized> = Vec::new();
+   |                                     ^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `dyn Trait`
+note: required by a bound in `Vec`
+  --> $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
+   |
+LL | pub struct Vec<T, #[unstable(feature = "allocator_api", issue = "32838")] A: Allocator = Global> {
+   |                ^ required by this bound in `Vec`
+
+error: aborting due to 4 previous errors
+
+Some errors have detailed explanations: E0225, E0277.
+For more information about an error, try `rustc --explain E0225`.