Use `PredicateObligation`s instead of `Predicate`s

Keep more information about trait binding failures.

28 files changed, 33 insertions, 28 deletions

diff --git a/src/test/ui/wf/wf-const-type.stderr b/src/test/ui/wf/wf-const-type.stderr
index 531aadc25dd..22f31c9f79f 100644
--- a/src/test/ui/wf/wf-const-type.stderr
+++ b/src/test/ui/wf/wf-const-type.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `NotCopy: std::marker::Copy` is not satisfied
   --> $DIR/wf-const-type.rs:10:12
    |
 LL | struct IsCopy<T:Copy> { t: T }
-   | --------------------- required by `IsCopy`
+   |        ------   ---- required by this bound in `IsCopy`
 ...
 LL | const FOO: IsCopy<Option<NotCopy>> = IsCopy { t: None };
    |            ^^^^^^^^^^^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `NotCopy`
diff --git a/src/test/ui/wf/wf-enum-bound.stderr b/src/test/ui/wf/wf-enum-bound.stderr
index f70f67d414f..88d8c599022 100644
--- a/src/test/ui/wf/wf-enum-bound.stderr
+++ b/src/test/ui/wf/wf-enum-bound.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `U: std::marker::Copy` is not satisfied
   --> $DIR/wf-enum-bound.rs:10:14
    |
 LL | trait ExtraCopy<T:Copy> { }
-   | ----------------------- required by `ExtraCopy`
+   |       ---------   ---- required by this bound in `ExtraCopy`
 ...
 LL |     where T: ExtraCopy<U>
    |              ^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `U`
diff --git a/src/test/ui/wf/wf-enum-fields-struct-variant.stderr b/src/test/ui/wf/wf-enum-fields-struct-variant.stderr
index 8634b7dba5c..d45ab952987 100644
--- a/src/test/ui/wf/wf-enum-fields-struct-variant.stderr
+++ b/src/test/ui/wf/wf-enum-fields-struct-variant.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `A: std::marker::Copy` is not satisfied
   --> $DIR/wf-enum-fields-struct-variant.rs:13:9
    |
 LL | struct IsCopy<T:Copy> {
-   | --------------------- required by `IsCopy`
+   |        ------   ---- required by this bound in `IsCopy`
 ...
 LL |         f: IsCopy<A>
    |         ^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `A`
diff --git a/src/test/ui/wf/wf-enum-fields.stderr b/src/test/ui/wf/wf-enum-fields.stderr
index a22b2d11a91..013407bcc68 100644
--- a/src/test/ui/wf/wf-enum-fields.stderr
+++ b/src/test/ui/wf/wf-enum-fields.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `A: std::marker::Copy` is not satisfied
   --> $DIR/wf-enum-fields.rs:12:17
    |
 LL | struct IsCopy<T:Copy> {
-   | --------------------- required by `IsCopy`
+   |        ------   ---- required by this bound in `IsCopy`
 ...
 LL |     SomeVariant(IsCopy<A>)
    |                 ^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `A`
diff --git a/src/test/ui/wf/wf-fn-where-clause.rs b/src/test/ui/wf/wf-fn-where-clause.rs
index 5fd567bd32d..adae536138b 100644
--- a/src/test/ui/wf/wf-fn-where-clause.rs
+++ b/src/test/ui/wf/wf-fn-where-clause.rs
@@ -13,5 +13,8 @@ fn bar() where Vec<dyn Copy>:, {}
 //~^ ERROR E0277
 //~| ERROR E0038
 
+struct Vec<T> {
+    t: T,
+}
 
 fn main() { }
diff --git a/src/test/ui/wf/wf-fn-where-clause.stderr b/src/test/ui/wf/wf-fn-where-clause.stderr
index cf1aeac7e3e..c5a7a5b0611 100644
--- a/src/test/ui/wf/wf-fn-where-clause.stderr
+++ b/src/test/ui/wf/wf-fn-where-clause.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `U: std::marker::Copy` is not satisfied
   --> $DIR/wf-fn-where-clause.rs:8:24
    |
 LL | trait ExtraCopy<T:Copy> { }
-   | ----------------------- required by `ExtraCopy`
+   |       ---------   ---- required by this bound in `ExtraCopy`
 LL | 
 LL | fn foo<T,U>() where T: ExtraCopy<U>
    |                        ^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `U`
@@ -17,10 +17,12 @@ error[E0277]: the size for values of type `(dyn std::marker::Copy + 'static)` ca
    |
 LL | fn bar() where Vec<dyn Copy>:, {}
    |                ^^^^^^^^^^^^^ doesn't have a size known at compile-time
+...
+LL | struct Vec<T> {
+   |        --- - required by this bound in `Vec`
    |
    = help: the trait `std::marker::Sized` is not implemented for `(dyn std::marker::Copy + 'static)`
    = note: to learn more, visit <https://doc.rust-lang.org/book/ch19-04-advanced-types.html#dynamically-sized-types-and-the-sized-trait>
-   = note: required by `std::vec::Vec`
 
 error[E0038]: the trait `std::marker::Copy` cannot be made into an object
   --> $DIR/wf-fn-where-clause.rs:12:16
diff --git a/src/test/ui/wf/wf-impl-associated-type-trait.stderr b/src/test/ui/wf/wf-impl-associated-type-trait.stderr
index d44a6f01a47..7312233aa54 100644
--- a/src/test/ui/wf/wf-impl-associated-type-trait.stderr
+++ b/src/test/ui/wf/wf-impl-associated-type-trait.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `T: MyHash` is not satisfied
   --> $DIR/wf-impl-associated-type-trait.rs:17:5
    |
 LL | pub struct MySet<T:MyHash> {
-   | -------------------------- required by `MySet`
+   |            -----   ------ required by this bound in `MySet`
 ...
 LL |     type Bar = MySet<T>;
    |     ^^^^^^^^^^^^^^^^^^^^ the trait `MyHash` is not implemented for `T`
diff --git a/src/test/ui/wf/wf-in-fn-arg.stderr b/src/test/ui/wf/wf-in-fn-arg.stderr
index 907701440aa..67a5562b6bc 100644
--- a/src/test/ui/wf/wf-in-fn-arg.stderr
+++ b/src/test/ui/wf/wf-in-fn-arg.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `T: std::marker::Copy` is not satisfied
   --> $DIR/wf-in-fn-arg.rs:10:14
    |
 LL | struct MustBeCopy<T:Copy> {
-   | ------------------------- required by `MustBeCopy`
+   |        ----------   ---- required by this bound in `MustBeCopy`
 ...
 LL | fn bar<T>(_: &MustBeCopy<T>)
    |              ^^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `T`
diff --git a/src/test/ui/wf/wf-in-fn-ret.stderr b/src/test/ui/wf/wf-in-fn-ret.stderr
index 2ed4eecefe1..545ee559b3f 100644
--- a/src/test/ui/wf/wf-in-fn-ret.stderr
+++ b/src/test/ui/wf/wf-in-fn-ret.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `T: std::marker::Copy` is not satisfied
   --> $DIR/wf-in-fn-ret.rs:10:16
    |
 LL | struct MustBeCopy<T:Copy> {
-   | ------------------------- required by `MustBeCopy`
+   |        ----------   ---- required by this bound in `MustBeCopy`
 ...
 LL | fn bar<T>() -> MustBeCopy<T>
    |                ^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `T`
diff --git a/src/test/ui/wf/wf-in-fn-type-arg.stderr b/src/test/ui/wf/wf-in-fn-type-arg.stderr
index 0c699838abd..0d8c6b14c56 100644
--- a/src/test/ui/wf/wf-in-fn-type-arg.stderr
+++ b/src/test/ui/wf/wf-in-fn-type-arg.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `T: std::marker::Copy` is not satisfied
   --> $DIR/wf-in-fn-type-arg.rs:9:5
    |
 LL | struct MustBeCopy<T:Copy> {
-   | ------------------------- required by `MustBeCopy`
+   |        ----------   ---- required by this bound in `MustBeCopy`
 ...
 LL |     x: fn(MustBeCopy<T>)
    |     ^^^^^^^^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `T`
diff --git a/src/test/ui/wf/wf-in-fn-type-ret.stderr b/src/test/ui/wf/wf-in-fn-type-ret.stderr
index 3429ab89ffb..b7c8bf303f3 100644
--- a/src/test/ui/wf/wf-in-fn-type-ret.stderr
+++ b/src/test/ui/wf/wf-in-fn-type-ret.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `T: std::marker::Copy` is not satisfied
   --> $DIR/wf-in-fn-type-ret.rs:9:5
    |
 LL | struct MustBeCopy<T:Copy> {
-   | ------------------------- required by `MustBeCopy`
+   |        ----------   ---- required by this bound in `MustBeCopy`
 ...
 LL |     x: fn() -> MustBeCopy<T>
    |     ^^^^^^^^^^^^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `T`
diff --git a/src/test/ui/wf/wf-in-fn-where-clause.stderr b/src/test/ui/wf/wf-in-fn-where-clause.stderr
index d33749d795c..e54cc17ccbe 100644
--- a/src/test/ui/wf/wf-in-fn-where-clause.stderr
+++ b/src/test/ui/wf/wf-in-fn-where-clause.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `U: std::marker::Copy` is not satisfied
   --> $DIR/wf-in-fn-where-clause.rs:10:14
    |
 LL | trait MustBeCopy<T:Copy> {
-   | ------------------------ required by `MustBeCopy`
+   |       ----------   ---- required by this bound in `MustBeCopy`
 ...
 LL |     where T: MustBeCopy<U>
    |              ^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `U`
diff --git a/src/test/ui/wf/wf-in-obj-type-trait.stderr b/src/test/ui/wf/wf-in-obj-type-trait.stderr
index 605dc497849..699c3fe1a63 100644
--- a/src/test/ui/wf/wf-in-obj-type-trait.stderr
+++ b/src/test/ui/wf/wf-in-obj-type-trait.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `T: std::marker::Copy` is not satisfied
   --> $DIR/wf-in-obj-type-trait.rs:11:5
    |
 LL | struct MustBeCopy<T:Copy> {
-   | ------------------------- required by `MustBeCopy`
+   |        ----------   ---- required by this bound in `MustBeCopy`
 ...
 LL |     x: dyn Object<MustBeCopy<T>>
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `T`
diff --git a/src/test/ui/wf/wf-inherent-impl-method-where-clause.stderr b/src/test/ui/wf/wf-inherent-impl-method-where-clause.stderr
index da2f8085a8a..172e763650a 100644
--- a/src/test/ui/wf/wf-inherent-impl-method-where-clause.stderr
+++ b/src/test/ui/wf/wf-inherent-impl-method-where-clause.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `U: std::marker::Copy` is not satisfied
   --> $DIR/wf-inherent-impl-method-where-clause.rs:12:27
    |
 LL | trait ExtraCopy<T:Copy> { }
-   | ----------------------- required by `ExtraCopy`
+   |       ---------   ---- required by this bound in `ExtraCopy`
 ...
 LL |     fn foo(self) where T: ExtraCopy<U>
    |                           ^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `U`
diff --git a/src/test/ui/wf/wf-inherent-impl-where-clause.stderr b/src/test/ui/wf/wf-inherent-impl-where-clause.stderr
index 28d5bc62556..1ac5aba3cad 100644
--- a/src/test/ui/wf/wf-inherent-impl-where-clause.stderr
+++ b/src/test/ui/wf/wf-inherent-impl-where-clause.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `U: std::marker::Copy` is not satisfied
   --> $DIR/wf-inherent-impl-where-clause.rs:11:29
    |
 LL | trait ExtraCopy<T:Copy> { }
-   | ----------------------- required by `ExtraCopy`
+   |       ---------   ---- required by this bound in `ExtraCopy`
 ...
 LL | impl<T,U> Foo<T,U> where T: ExtraCopy<U>
    |                             ^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `U`
diff --git a/src/test/ui/wf/wf-static-type.stderr b/src/test/ui/wf/wf-static-type.stderr
index 05a628d7c3e..ec31710e861 100644
--- a/src/test/ui/wf/wf-static-type.stderr
+++ b/src/test/ui/wf/wf-static-type.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `NotCopy: std::marker::Copy` is not satisfied
   --> $DIR/wf-static-type.rs:10:13
    |
 LL | struct IsCopy<T:Copy> { t: T }
-   | --------------------- required by `IsCopy`
+   |        ------   ---- required by this bound in `IsCopy`
 ...
 LL | static FOO: IsCopy<Option<NotCopy>> = IsCopy { t: None };
    |             ^^^^^^^^^^^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `NotCopy`
diff --git a/src/test/ui/wf/wf-struct-bound.stderr b/src/test/ui/wf/wf-struct-bound.stderr
index 07e569ddac1..848a2eb8bee 100644
--- a/src/test/ui/wf/wf-struct-bound.stderr
+++ b/src/test/ui/wf/wf-struct-bound.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `U: std::marker::Copy` is not satisfied
   --> $DIR/wf-struct-bound.rs:10:14
    |
 LL | trait ExtraCopy<T:Copy> { }
-   | ----------------------- required by `ExtraCopy`
+   |       ---------   ---- required by this bound in `ExtraCopy`
 ...
 LL |     where T: ExtraCopy<U>
    |              ^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `U`
diff --git a/src/test/ui/wf/wf-struct-field.stderr b/src/test/ui/wf/wf-struct-field.stderr
index f3bce24eace..a748a1c9c39 100644
--- a/src/test/ui/wf/wf-struct-field.stderr
+++ b/src/test/ui/wf/wf-struct-field.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `A: std::marker::Copy` is not satisfied
   --> $DIR/wf-struct-field.rs:12:5
    |
 LL | struct IsCopy<T:Copy> {
-   | --------------------- required by `IsCopy`
+   |        ------   ---- required by this bound in `IsCopy`
 ...
 LL |     data: IsCopy<A>
    |     ^^^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `A`
diff --git a/src/test/ui/wf/wf-trait-associated-type-bound.stderr b/src/test/ui/wf/wf-trait-associated-type-bound.stderr
index 6cf7f2069b6..e568acabcd0 100644
--- a/src/test/ui/wf/wf-trait-associated-type-bound.stderr
+++ b/src/test/ui/wf/wf-trait-associated-type-bound.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `T: std::marker::Copy` is not satisfied
   --> $DIR/wf-trait-associated-type-bound.rs:10:17
    |
 LL | trait ExtraCopy<T:Copy> { }
-   | ----------------------- required by `ExtraCopy`
+   |       ---------   ---- required by this bound in `ExtraCopy`
 ...
 LL |     type Type1: ExtraCopy<T>;
    |                 ^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `T`
diff --git a/src/test/ui/wf/wf-trait-associated-type-trait.stderr b/src/test/ui/wf/wf-trait-associated-type-trait.stderr
index 93cb948cdbf..915f660f54d 100644
--- a/src/test/ui/wf/wf-trait-associated-type-trait.stderr
+++ b/src/test/ui/wf/wf-trait-associated-type-trait.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `<Self as SomeTrait>::Type1: std::marker::Copy` is
   --> $DIR/wf-trait-associated-type-trait.rs:11:5
    |
 LL | struct IsCopy<T:Copy> { x: T }
-   | --------------------- required by `IsCopy`
+   |        ------   ---- required by this bound in `IsCopy`
 LL | 
 LL | trait SomeTrait {
    |                - help: consider further restricting the associated type: `where <Self as SomeTrait>::Type1: std::marker::Copy`
diff --git a/src/test/ui/wf/wf-trait-bound.stderr b/src/test/ui/wf/wf-trait-bound.stderr
index b8ffad6d180..0db29621e31 100644
--- a/src/test/ui/wf/wf-trait-bound.stderr
+++ b/src/test/ui/wf/wf-trait-bound.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `U: std::marker::Copy` is not satisfied
   --> $DIR/wf-trait-bound.rs:10:14
    |
 LL | trait ExtraCopy<T:Copy> { }
-   | ----------------------- required by `ExtraCopy`
+   |       ---------   ---- required by this bound in `ExtraCopy`
 ...
 LL |     where T: ExtraCopy<U>
    |              ^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `U`
diff --git a/src/test/ui/wf/wf-trait-default-fn-arg.stderr b/src/test/ui/wf/wf-trait-default-fn-arg.stderr
index 6a97d31cf3e..55fc202ca51 100644
--- a/src/test/ui/wf/wf-trait-default-fn-arg.stderr
+++ b/src/test/ui/wf/wf-trait-default-fn-arg.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `Self: std::cmp::Eq` is not satisfied
   --> $DIR/wf-trait-default-fn-arg.rs:11:22
    |
 LL | struct Bar<T:Eq+?Sized> { value: Box<T> }
-   | ----------------------- required by `Bar`
+   |        ---   -- required by this bound in `Bar`
 ...
 LL |     fn bar(&self, x: &Bar<Self>) {
    |                      ^^^^^^^^^^ - help: consider further restricting `Self`: `where Self: std::cmp::Eq`
diff --git a/src/test/ui/wf/wf-trait-default-fn-ret.stderr b/src/test/ui/wf/wf-trait-default-fn-ret.stderr
index 36c1e486269..00b153317ab 100644
--- a/src/test/ui/wf/wf-trait-default-fn-ret.stderr
+++ b/src/test/ui/wf/wf-trait-default-fn-ret.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `Self: std::cmp::Eq` is not satisfied
   --> $DIR/wf-trait-default-fn-ret.rs:11:22
    |
 LL | struct Bar<T:Eq+?Sized> { value: Box<T> }
-   | ----------------------- required by `Bar`
+   |        ---   -- required by this bound in `Bar`
 ...
 LL |     fn bar(&self) -> Bar<Self> {
    |                      ^^^^^^^^^- help: consider further restricting `Self`: `where Self: std::cmp::Eq`
diff --git a/src/test/ui/wf/wf-trait-default-fn-where-clause.stderr b/src/test/ui/wf/wf-trait-default-fn-where-clause.stderr
index 6b63feaba89..97210a8aa6a 100644
--- a/src/test/ui/wf/wf-trait-default-fn-where-clause.stderr
+++ b/src/test/ui/wf/wf-trait-default-fn-where-clause.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `Self: std::cmp::Eq` is not satisfied
   --> $DIR/wf-trait-default-fn-where-clause.rs:11:31
    |
 LL | trait Bar<T:Eq+?Sized> { }
-   | ---------------------- required by `Bar`
+   |       ---   -- required by this bound in `Bar`
 ...
 LL |     fn bar<A>(&self) where A: Bar<Self> {
    |                               ^^^^^^^^^- help: consider further restricting `Self`: `, Self: std::cmp::Eq`
diff --git a/src/test/ui/wf/wf-trait-fn-arg.stderr b/src/test/ui/wf/wf-trait-fn-arg.stderr
index 69e2ab72912..190721492a2 100644
--- a/src/test/ui/wf/wf-trait-fn-arg.stderr
+++ b/src/test/ui/wf/wf-trait-fn-arg.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `Self: std::cmp::Eq` is not satisfied
   --> $DIR/wf-trait-fn-arg.rs:10:22
    |
 LL | struct Bar<T:Eq+?Sized> { value: Box<T> }
-   | ----------------------- required by `Bar`
+   |        ---   -- required by this bound in `Bar`
 ...
 LL |     fn bar(&self, x: &Bar<Self>);
    |                      ^^^^^^^^^^ - help: consider further restricting `Self`: `where Self: std::cmp::Eq`
diff --git a/src/test/ui/wf/wf-trait-fn-ret.stderr b/src/test/ui/wf/wf-trait-fn-ret.stderr
index bfc6265662e..b8d10f4f396 100644
--- a/src/test/ui/wf/wf-trait-fn-ret.stderr
+++ b/src/test/ui/wf/wf-trait-fn-ret.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `Self: std::cmp::Eq` is not satisfied
   --> $DIR/wf-trait-fn-ret.rs:10:22
    |
 LL | struct Bar<T:Eq+?Sized> { value: Box<T> }
-   | ----------------------- required by `Bar`
+   |        ---   -- required by this bound in `Bar`
 ...
 LL |     fn bar(&self) -> &Bar<Self>;
    |                      ^^^^^^^^^^- help: consider further restricting `Self`: `where Self: std::cmp::Eq`
diff --git a/src/test/ui/wf/wf-trait-fn-where-clause.stderr b/src/test/ui/wf/wf-trait-fn-where-clause.stderr
index ec8f02c9c4f..c138da032ce 100644
--- a/src/test/ui/wf/wf-trait-fn-where-clause.stderr
+++ b/src/test/ui/wf/wf-trait-fn-where-clause.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `Self: std::cmp::Eq` is not satisfied
   --> $DIR/wf-trait-fn-where-clause.rs:10:49
    |
 LL | struct Bar<T:Eq+?Sized> { value: Box<T> }
-   | ----------------------- required by `Bar`
+   |        ---   -- required by this bound in `Bar`
 ...
 LL |     fn bar(&self) where Self: Sized, Bar<Self>: Copy;
    |                                                 ^^^^- help: consider further restricting `Self`: `, Self: std::cmp::Eq`
diff --git a/src/test/ui/wf/wf-trait-superbound.stderr b/src/test/ui/wf/wf-trait-superbound.stderr
index 88b4bec0451..5310939af9c 100644
--- a/src/test/ui/wf/wf-trait-superbound.stderr
+++ b/src/test/ui/wf/wf-trait-superbound.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `T: std::marker::Copy` is not satisfied
   --> $DIR/wf-trait-superbound.rs:9:21
    |
 LL | trait ExtraCopy<T:Copy> { }
-   | ----------------------- required by `ExtraCopy`
+   |       ---------   ---- required by this bound in `ExtraCopy`
 LL | 
 LL | trait SomeTrait<T>: ExtraCopy<T> {
    |                     ^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `T`