rebase and update fixed crashes

Author: lcnr

tests/crashes/118987.rs

@@ -1,4 +1,4 @@
-//@ known-bug: #118987
+// regression test for #118987
 #![feature(specialization)] //~ WARN the feature `specialization` is incomplete
 
 trait Assoc {
@@ -15,3 +15,5 @@ trait Foo {}
 
 impl Foo for <u8 as Assoc>::Output {}
 impl Foo for <u16 as Assoc>::Output {}
+//~^ ERROR the trait bound `u16: Assoc` is not satisfied
+fn main() {}

tests/crashes/118987-2.rs renamed to tests/ui/specialization/coherence/default-impl-normalization-ambig-2.rs

@@ -0,0 +1,21 @@
+warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/default-impl-normalization-ambig-2.rs:2:12
+   |
+LL | #![feature(specialization)]
+   |            ^^^^^^^^^^^^^^
+   |
+   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
+   = help: consider using `min_specialization` instead, which is more stable and complete
+   = note: `#[warn(incomplete_features)]` on by default
+
+error[E0277]: the trait bound `u16: Assoc` is not satisfied
+  --> $DIR/default-impl-normalization-ambig-2.rs:17:14
+   |
+LL | impl Foo for <u16 as Assoc>::Output {}
+   |              ^^^^^^^^^^^^^^^^^^^^^^ the trait `Assoc` is not implemented for `u16`
+   |
+   = help: the trait `Assoc` is implemented for `u8`
+
+error: aborting due to 1 previous error; 1 warning emitted
+
+For more information about this error, try `rustc --explain E0277`.

tests/ui/specialization/coherence/default-impl-normalization-ambig-2.stderr

@@ -1,5 +1,5 @@
-//@ known-bug: #74299
-#![feature(specialization)]
+// regression test for #73299.
+#![feature(specialization)] //~ WARN the feature `specialization` is incomplete
 
 trait X {
     type U;
@@ -18,6 +18,7 @@ trait Y {
 
 impl Y for <() as X>::U {}
 impl Y for <i32 as X>::U {}
+//~^ ERROR conflicting implementations of trait `Y` for type `<() as X>::U`
 
 fn main() {
     ().f().g();

tests/crashes/74299.rs renamed to tests/ui/specialization/coherence/default-item-normalization-ambig-1.rs

@@ -0,0 +1,21 @@
+warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/default-item-normalization-ambig-1.rs:2:12
+   |
+LL | #![feature(specialization)]
+   |            ^^^^^^^^^^^^^^
+   |
+   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
+   = help: consider using `min_specialization` instead, which is more stable and complete
+   = note: `#[warn(incomplete_features)]` on by default
+
+error[E0119]: conflicting implementations of trait `Y` for type `<() as X>::U`
+  --> $DIR/default-item-normalization-ambig-1.rs:20:1
+   |
+LL | impl Y for <() as X>::U {}
+   | ----------------------- first implementation here
+LL | impl Y for <i32 as X>::U {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `<() as X>::U`
+
+error: aborting due to 1 previous error; 1 warning emitted
+
+For more information about this error, try `rustc --explain E0119`.

tests/ui/specialization/coherence/default-item-normalization-ambig-1.stderr

@@ -1,9 +1,11 @@
-//@ known-bug: #124207
 #![feature(transmutability)]
 #![feature(type_alias_impl_trait)]
 trait OpaqueTrait {}
 type OpaqueType = impl OpaqueTrait;
+//~^ ERROR unconstrained opaque type
 trait AnotherTrait {}
 impl<T: std::mem::TransmuteFrom<(), ()>> AnotherTrait for T {}
+//~^ ERROR type provided when a constant was expected
 impl AnotherTrait for OpaqueType {}
+//~^ ERROR conflicting implementations of trait `AnotherTrait`
 pub fn main() {}

tests/crashes/124207.rs renamed to tests/ui/transmutability/malformed-program-gracefulness/coherence-bikeshed-intrinsic-from.rs

@@ -0,0 +1,27 @@
+error: unconstrained opaque type
+  --> $DIR/coherence-bikeshed-intrinsic-from.rs:4:19
+   |
+LL | type OpaqueType = impl OpaqueTrait;
+   |                   ^^^^^^^^^^^^^^^^
+   |
+   = note: `OpaqueType` must be used in combination with a concrete type within the same module
+
+error[E0747]: type provided when a constant was expected
+  --> $DIR/coherence-bikeshed-intrinsic-from.rs:7:37
+   |
+LL | impl<T: std::mem::TransmuteFrom<(), ()>> AnotherTrait for T {}
+   |                                     ^^
+
+error[E0119]: conflicting implementations of trait `AnotherTrait`
+  --> $DIR/coherence-bikeshed-intrinsic-from.rs:9:1
+   |
+LL | impl<T: std::mem::TransmuteFrom<(), ()>> AnotherTrait for T {}
+   | ----------------------------------------------------------- first implementation here
+LL |
+LL | impl AnotherTrait for OpaqueType {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation
+
+error: aborting due to 3 previous errors
+
+Some errors have detailed explanations: E0119, E0747.
+For more information about an error, try `rustc --explain E0119`.