Merge pull request #2617 from rust-lang/rustc-pull

Rustc pull update

Author: tshepang

tests/fail/layout_cycle.stderr

@@ -2,29 +2,20 @@ error[E0391]: cycle detected when computing layout of `S<S<()>>`
    |
    = note: ...which requires computing layout of `<S<()> as Tr>::I`...
    = note: ...which again requires computing layout of `S<S<()>>`, completing the cycle
+note: cycle used when const-evaluating + checking `core::mem::SizedTypeProperties::SIZE`
+  --> RUSTLIB/core/src/mem/mod.rs:LL:CC
+   |
+LL |     const SIZE: usize = intrinsics::size_of::<Self>();
+   |     ^^^^^^^^^^^^^^^^^
    = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information
 
-error: post-monomorphization error: a cycle occurred during layout computation
+error[E0080]: a cycle occurred during layout computation
   --> RUSTLIB/core/src/mem/mod.rs:LL:CC
    |
-LL |     intrinsics::size_of::<T>()
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ post-monomorphization error occurred here
-   |
-   = note: BACKTRACE:
-   = note: inside `std::mem::size_of::<S<S<()>>>` at RUSTLIB/core/src/mem/mod.rs:LL:CC
-note: inside `foo::<S<()>>`
-  --> tests/fail/layout_cycle.rs:LL:CC
-   |
-LL |     mem::size_of::<S<T>>()
-   |     ^^^^^^^^^^^^^^^^^^^^^^
-note: inside `main`
-  --> tests/fail/layout_cycle.rs:LL:CC
-   |
-LL |     println!("{}", foo::<S<()>>());
-   |                    ^^^^^^^^^^^^^^
-
-note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
+LL |     const SIZE: usize = intrinsics::size_of::<Self>();
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ evaluation of `<S<S<()>> as std::mem::SizedTypeProperties>::SIZE` failed here
 
 error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0391`.
+Some errors have detailed explanations: E0080, E0391.
+For more information about an error, try `rustc --explain E0080`.

tests/pass/pattern-types.rs

@@ -0,0 +1,18 @@
+#![feature(pattern_types, pattern_type_macro, sized_hierarchy)]
+#![allow(dead_code)]
+
+use std::marker::PointeeSized;
+use std::mem::transmute;
+
+pub struct NonNull<T: PointeeSized> {
+    pointer: std::pat::pattern_type!(*const T is !null),
+}
+
+trait Trait {}
+impl Trait for () {}
+
+fn main() {
+    unsafe {
+        let _: NonNull<dyn Trait> = NonNull { pointer: transmute(&mut () as *mut dyn Trait) };
+    }
+}