Auto merge of #69914 - Centril:rollup-wtmdinz, r=Centril

Rollup of 10 pull requests

Successful merges:

 - #66059 (mem::zeroed/uninit: panic on types that do not permit zero-initialization)
 - #69373 (Stabilize const for integer {to,from}_{be,le,ne}_bytes methods)
 - #69591 (Use TypeRelating for instantiating query responses)
 - #69625 (Implement nth, last, and count for iter::Copied)
 - #69645 (const forget tests)
 - #69766 (Make Point `Copy` in arithmetic documentation)
 - #69825 (make `mem::discriminant` const)
 - #69859 (fix #62456)
 - #69891 (Exhaustiveness checking, `Matrix::push`: recursively expand or-patterns)
 - #69896 (parse: Tweak the function parameter edition check)

Failed merges:

r? @ghost

19 files changed, 341 insertions, 105 deletions

diff --git a/src/test/ui/anon-params-denied-2018.rs b/src/test/ui/anon-params/anon-params-denied-2018.rs
index 5721f5d2357..5721f5d2357 100644
--- a/src/test/ui/anon-params-denied-2018.rs
+++ b/src/test/ui/anon-params/anon-params-denied-2018.rs
diff --git a/src/test/ui/anon-params-denied-2018.stderr b/src/test/ui/anon-params/anon-params-denied-2018.stderr
index e7a806a8468..e7a806a8468 100644
--- a/src/test/ui/anon-params-denied-2018.stderr
+++ b/src/test/ui/anon-params/anon-params-denied-2018.stderr
diff --git a/src/test/ui/anon-params-deprecated.fixed b/src/test/ui/anon-params/anon-params-deprecated.fixed
index fe42113eb2e..fe42113eb2e 100644
--- a/src/test/ui/anon-params-deprecated.fixed
+++ b/src/test/ui/anon-params/anon-params-deprecated.fixed
diff --git a/src/test/ui/anon-params-deprecated.rs b/src/test/ui/anon-params/anon-params-deprecated.rs
index dc0357721ec..dc0357721ec 100644
--- a/src/test/ui/anon-params-deprecated.rs
+++ b/src/test/ui/anon-params/anon-params-deprecated.rs
diff --git a/src/test/ui/anon-params-deprecated.stderr b/src/test/ui/anon-params/anon-params-deprecated.stderr
index 4520559845f..4520559845f 100644
--- a/src/test/ui/anon-params-deprecated.stderr
+++ b/src/test/ui/anon-params/anon-params-deprecated.stderr
diff --git a/src/test/ui/anon-params/anon-params-edition-hygiene.rs b/src/test/ui/anon-params/anon-params-edition-hygiene.rs
new file mode 100644
index 00000000000..14e11c5696f
--- /dev/null
+++ b/src/test/ui/anon-params/anon-params-edition-hygiene.rs
@@ -0,0 +1,10 @@
+// check-pass
+// edition:2018
+// aux-build:anon-params-edition-hygiene.rs
+
+#[macro_use]
+extern crate anon_params_edition_hygiene;
+
+generate_trait_2015!(u8);
+
+fn main() {}
diff --git a/src/test/ui/anon-params/auxiliary/anon-params-edition-hygiene.rs b/src/test/ui/anon-params/auxiliary/anon-params-edition-hygiene.rs
new file mode 100644
index 00000000000..aa4221becc2
--- /dev/null
+++ b/src/test/ui/anon-params/auxiliary/anon-params-edition-hygiene.rs
@@ -0,0 +1,12 @@
+// edition:2015
+
+#[macro_export]
+macro_rules! generate_trait_2015 {
+    ($Type: ident) => {
+        trait Trait {
+            fn method($Type) {}
+        }
+    };
+}
+
+fn main() {}
diff --git a/src/test/ui/const-generics/issues/issue-62456.rs b/src/test/ui/const-generics/issues/issue-62456.rs
new file mode 100644
index 00000000000..c5e6fe9104b
--- /dev/null
+++ b/src/test/ui/const-generics/issues/issue-62456.rs
@@ -0,0 +1,9 @@
+#![feature(const_generics)]
+//~^ WARN the feature `const_generics` is incomplete and may cause the compiler to crash
+
+fn foo<const N: usize>() {
+    let _ = [0u64; N + 1];
+    //~^ ERROR array lengths can't depend on generic parameters
+}
+
+fn main() {}
diff --git a/src/test/ui/const-generics/issues/issue-62456.stderr b/src/test/ui/const-generics/issues/issue-62456.stderr
new file mode 100644
index 00000000000..9cdccf8407c
--- /dev/null
+++ b/src/test/ui/const-generics/issues/issue-62456.stderr
@@ -0,0 +1,16 @@
+warning: the feature `const_generics` is incomplete and may cause the compiler to crash
+  --> $DIR/issue-62456.rs:1:12
+   |
+LL | #![feature(const_generics)]
+   |            ^^^^^^^^^^^^^^
+   |
+   = note: `#[warn(incomplete_features)]` on by default
+
+error: array lengths can't depend on generic parameters
+  --> $DIR/issue-62456.rs:5:20
+   |
+LL |     let _ = [0u64; N + 1];
+   |                    ^^^^^
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/consts/const-int-conversion-rpass.rs b/src/test/ui/consts/const-int-conversion-rpass.rs
index d52dbbae1e7..6484169dd9a 100644
--- a/src/test/ui/consts/const-int-conversion-rpass.rs
+++ b/src/test/ui/consts/const-int-conversion-rpass.rs
@@ -1,7 +1,5 @@
 // run-pass
 
-#![feature(const_int_conversion)]
-
 const REVERSE: u32 = 0x12345678_u32.reverse_bits();
 const FROM_BE_BYTES: i32 = i32::from_be_bytes([0x12, 0x34, 0x56, 0x78]);
 const FROM_LE_BYTES: i32 = i32::from_le_bytes([0x12, 0x34, 0x56, 0x78]);
diff --git a/src/test/ui/consts/const_discriminant.rs b/src/test/ui/consts/const_discriminant.rs
new file mode 100644
index 00000000000..1ad5134e71c
--- /dev/null
+++ b/src/test/ui/consts/const_discriminant.rs
@@ -0,0 +1,40 @@
+// run-pass
+#![feature(const_discriminant)]
+#![allow(dead_code)]
+
+use std::mem::{discriminant, Discriminant};
+
+// `discriminant(const_expr)` may get const-propagated.
+// As we want to check that const-eval is equal to ordinary exection,
+// we wrap `const_expr` with a function which is not const to prevent this.
+#[inline(never)]
+fn identity<T>(x: T) -> T { x }
+
+enum Test {
+    A(u8),
+    B,
+    C { a: u8, b: u8 },
+}
+
+const TEST_A: Discriminant<Test> = discriminant(&Test::A(5));
+const TEST_A_OTHER: Discriminant<Test> = discriminant(&Test::A(17));
+const TEST_B: Discriminant<Test> = discriminant(&Test::B);
+
+enum Void {}
+
+enum SingleVariant {
+    V,
+    Never(Void),
+}
+
+const TEST_V: Discriminant<SingleVariant> = discriminant(&SingleVariant::V);
+
+fn main() {
+    assert_eq!(TEST_A, TEST_A_OTHER);
+    assert_eq!(TEST_A, discriminant(identity(&Test::A(17))));
+    assert_eq!(TEST_B, discriminant(identity(&Test::B)));
+    assert_ne!(TEST_A, TEST_B);
+    assert_ne!(TEST_B, discriminant(identity(&Test::C { a: 42, b: 7 })));
+
+    assert_eq!(TEST_V, discriminant(identity(&SingleVariant::V)));
+}
diff --git a/src/test/ui/intrinsics/panic-uninitialized-zeroed.rs b/src/test/ui/intrinsics/panic-uninitialized-zeroed.rs
new file mode 100644
index 00000000000..02f8ecaa4ee
--- /dev/null
+++ b/src/test/ui/intrinsics/panic-uninitialized-zeroed.rs
@@ -0,0 +1,170 @@
+// run-pass
+// ignore-wasm32-bare compiled with panic=abort by default
+
+// This test checks panic emitted from `mem::{uninitialized,zeroed}`.
+
+#![feature(never_type)]
+#![allow(deprecated, invalid_value)]
+
+use std::{
+    mem::{self, MaybeUninit, ManuallyDrop},
+    panic,
+    ptr::NonNull,
+    num,
+};
+
+#[allow(dead_code)]
+struct Foo {
+    x: u8,
+    y: !,
+}
+
+enum Bar {}
+
+#[allow(dead_code)]
+enum OneVariant { Variant(i32) }
+
+// An enum with ScalarPair layout
+#[allow(dead_code)]
+enum LR {
+    Left(i64),
+    Right(i64),
+}
+#[allow(dead_code, non_camel_case_types)]
+enum LR_NonZero {
+    Left(num::NonZeroI64),
+    Right(num::NonZeroI64),
+}
+
+fn test_panic_msg<T>(op: impl (FnOnce() -> T) + panic::UnwindSafe, msg: &str) {
+    let err = panic::catch_unwind(op).err();
+    assert_eq!(
+        err.as_ref().and_then(|a| a.downcast_ref::<String>()).map(|s| &**s),
+        Some(msg)
+    );
+}
+
+fn main() {
+    unsafe {
+        // Uninhabited types
+        test_panic_msg(
+            || mem::uninitialized::<!>(),
+            "attempted to instantiate uninhabited type `!`"
+        );
+        test_panic_msg(
+            || mem::zeroed::<!>(),
+            "attempted to instantiate uninhabited type `!`"
+        );
+        test_panic_msg(
+            || MaybeUninit::<!>::uninit().assume_init(),
+            "attempted to instantiate uninhabited type `!`"
+        );
+
+        test_panic_msg(
+            || mem::uninitialized::<Foo>(),
+            "attempted to instantiate uninhabited type `Foo`"
+        );
+        test_panic_msg(
+            || mem::zeroed::<Foo>(),
+            "attempted to instantiate uninhabited type `Foo`"
+        );
+        test_panic_msg(
+            || MaybeUninit::<Foo>::uninit().assume_init(),
+            "attempted to instantiate uninhabited type `Foo`"
+        );
+
+        test_panic_msg(
+            || mem::uninitialized::<Bar>(),
+            "attempted to instantiate uninhabited type `Bar`"
+        );
+        test_panic_msg(
+            || mem::zeroed::<Bar>(),
+            "attempted to instantiate uninhabited type `Bar`"
+        );
+        test_panic_msg(
+            || MaybeUninit::<Bar>::uninit().assume_init(),
+            "attempted to instantiate uninhabited type `Bar`"
+        );
+
+        // Types that do not like zero-initialziation
+        test_panic_msg(
+            || mem::uninitialized::<fn()>(),
+            "attempted to leave type `fn()` uninitialized, which is invalid"
+        );
+        test_panic_msg(
+            || mem::zeroed::<fn()>(),
+            "attempted to zero-initialize type `fn()`, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::uninitialized::<*const dyn Send>(),
+            "attempted to leave type `*const dyn std::marker::Send` uninitialized, which is invalid"
+        );
+        test_panic_msg(
+            || mem::zeroed::<*const dyn Send>(),
+            "attempted to zero-initialize type `*const dyn std::marker::Send`, which is invalid"
+        );
+
+        /* FIXME(#66151) we conservatively do not error here yet.
+        test_panic_msg(
+            || mem::uninitialized::<LR_NonZero>(),
+            "attempted to leave type `LR_NonZero` uninitialized, which is invalid"
+        );
+        test_panic_msg(
+            || mem::zeroed::<LR_NonZero>(),
+            "attempted to zero-initialize type `LR_NonZero`, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::uninitialized::<ManuallyDrop<LR_NonZero>>(),
+            "attempted to leave type `std::mem::ManuallyDrop<LR_NonZero>` uninitialized, \
+             which is invalid"
+        );
+        test_panic_msg(
+            || mem::zeroed::<ManuallyDrop<LR_NonZero>>(),
+            "attempted to zero-initialize type `std::mem::ManuallyDrop<LR_NonZero>`, \
+             which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::uninitialized::<(NonNull<u32>, u32, u32)>(),
+            "attempted to leave type `(std::ptr::NonNull<u32>, u32, u32)` uninitialized, \
+                which is invalid"
+        );
+        test_panic_msg(
+            || mem::zeroed::<(NonNull<u32>, u32, u32)>(),
+            "attempted to zero-initialize type `(std::ptr::NonNull<u32>, u32, u32)`, \
+                which is invalid"
+        );
+        */
+
+        // Types that can be zero, but not uninit.
+        test_panic_msg(
+            || mem::uninitialized::<bool>(),
+            "attempted to leave type `bool` uninitialized, which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<LR>(),
+            "attempted to leave type `LR` uninitialized, which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<ManuallyDrop<LR>>(),
+            "attempted to leave type `std::mem::ManuallyDrop<LR>` uninitialized, which is invalid"
+        );
+
+        // Some things that should work.
+        let _val = mem::zeroed::<bool>();
+        let _val = mem::zeroed::<LR>();
+        let _val = mem::zeroed::<ManuallyDrop<LR>>();
+        let _val = mem::zeroed::<OneVariant>();
+        let _val = mem::zeroed::<Option<&'static i32>>();
+        let _val = mem::zeroed::<MaybeUninit<NonNull<u32>>>();
+        let _val = mem::uninitialized::<MaybeUninit<bool>>();
+
+        // These are UB because they have not been officially blessed, but we await the resolution
+        // of <https://github.com/rust-lang/unsafe-code-guidelines/issues/71> before doing
+        // anything about that.
+        let _val = mem::uninitialized::<i32>();
+        let _val = mem::uninitialized::<*const ()>();
+    }
+}
diff --git a/src/test/ui/issues/issue-69602-type-err-during-codegen-ice.rs b/src/test/ui/issues/issue-69602-type-err-during-codegen-ice.rs
index 2c5257ce063..d060f26fb2a 100644
--- a/src/test/ui/issues/issue-69602-type-err-during-codegen-ice.rs
+++ b/src/test/ui/issues/issue-69602-type-err-during-codegen-ice.rs
@@ -19,4 +19,5 @@ impl TraitB for B { //~ ERROR not all trait items implemented, missing: `MyA`
 
 fn main() {
     let _ = [0; B::VALUE];
+    //~^ ERROR array lengths can't depend on generic parameters
 }
diff --git a/src/test/ui/issues/issue-69602-type-err-during-codegen-ice.stderr b/src/test/ui/issues/issue-69602-type-err-during-codegen-ice.stderr
index 8ae0f8b804c..c6b2b4d27a2 100644
--- a/src/test/ui/issues/issue-69602-type-err-during-codegen-ice.stderr
+++ b/src/test/ui/issues/issue-69602-type-err-during-codegen-ice.stderr
@@ -13,7 +13,13 @@ LL |     type MyA: TraitA;
 LL | impl TraitB for B {
    | ^^^^^^^^^^^^^^^^^ missing `MyA` in implementation
 
-error: aborting due to 2 previous errors
+error: array lengths can't depend on generic parameters
+  --> $DIR/issue-69602-type-err-during-codegen-ice.rs:21:17
+   |
+LL |     let _ = [0; B::VALUE];
+   |                 ^^^^^^^^
+
+error: aborting due to 3 previous errors
 
 Some errors have detailed explanations: E0046, E0437.
 For more information about an error, try `rustc --explain E0046`.
diff --git a/src/test/ui/never_type/panic-uninitialized-zeroed.rs b/src/test/ui/never_type/panic-uninitialized-zeroed.rs
deleted file mode 100644
index e0c30160b9e..00000000000
--- a/src/test/ui/never_type/panic-uninitialized-zeroed.rs
+++ /dev/null
@@ -1,102 +0,0 @@
-// run-pass
-// ignore-wasm32-bare compiled with panic=abort by default
-// This test checks that instantiating an uninhabited type via `mem::{uninitialized,zeroed}` results
-// in a runtime panic.
-
-#![feature(never_type)]
-#![allow(deprecated, invalid_value)]
-
-use std::{mem, panic};
-
-#[allow(dead_code)]
-struct Foo {
-    x: u8,
-    y: !,
-}
-
-enum Bar {}
-
-fn main() {
-    unsafe {
-        assert_eq!(
-            panic::catch_unwind(|| {
-                mem::uninitialized::<!>()
-            }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
-                s == "Attempted to instantiate uninhabited type !"
-            })),
-            Some(true)
-        );
-
-        assert_eq!(
-            panic::catch_unwind(|| {
-                mem::zeroed::<!>()
-            }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
-                s == "Attempted to instantiate uninhabited type !"
-            })),
-            Some(true)
-        );
-
-        assert_eq!(
-            panic::catch_unwind(|| {
-                mem::MaybeUninit::<!>::uninit().assume_init()
-            }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
-                s == "Attempted to instantiate uninhabited type !"
-            })),
-            Some(true)
-        );
-
-        assert_eq!(
-            panic::catch_unwind(|| {
-                mem::uninitialized::<Foo>()
-            }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
-                s == "Attempted to instantiate uninhabited type Foo"
-            })),
-            Some(true)
-        );
-
-        assert_eq!(
-            panic::catch_unwind(|| {
-                mem::zeroed::<Foo>()
-            }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
-                s == "Attempted to instantiate uninhabited type Foo"
-            })),
-            Some(true)
-        );
-
-        assert_eq!(
-            panic::catch_unwind(|| {
-                mem::MaybeUninit::<Foo>::uninit().assume_init()
-            }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
-                s == "Attempted to instantiate uninhabited type Foo"
-            })),
-            Some(true)
-        );
-
-        assert_eq!(
-            panic::catch_unwind(|| {
-                mem::uninitialized::<Bar>()
-            }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
-                s == "Attempted to instantiate uninhabited type Bar"
-            })),
-            Some(true)
-        );
-
-        assert_eq!(
-            panic::catch_unwind(|| {
-                mem::zeroed::<Bar>()
-            }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
-                s == "Attempted to instantiate uninhabited type Bar"
-            })),
-            Some(true)
-        );
-
-        assert_eq!(
-            panic::catch_unwind(|| {
-                mem::MaybeUninit::<Bar>::uninit().assume_init()
-            }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
-                s == "Attempted to instantiate uninhabited type Bar"
-            })),
-            Some(true)
-        );
-    }
-}
diff --git a/src/test/ui/nll/user-annotations/type-annotation-with-hrtb.rs b/src/test/ui/nll/user-annotations/type-annotation-with-hrtb.rs
new file mode 100644
index 00000000000..1f7c060386b
--- /dev/null
+++ b/src/test/ui/nll/user-annotations/type-annotation-with-hrtb.rs
@@ -0,0 +1,33 @@
+// Regression test for issue #69490
+
+// check-pass
+
+pub trait Trait<T> {
+    const S: &'static str;
+}
+
+impl<T> Trait<()> for T
+where
+    T: for<'a> Trait<&'a ()>,
+{
+    // Use of `T::S` here caused an ICE
+    const S: &'static str = T::S;
+}
+
+// Some similar cases that didn't ICE:
+
+impl<'a, T> Trait<()> for (T,)
+where
+    T: Trait<&'a ()>,
+{
+    const S: &'static str = T::S;
+}
+
+impl<T> Trait<()> for [T; 1]
+where
+    T: Trait<for<'a> fn(&'a ())>,
+{
+    const S: &'static str = T::S;
+}
+
+fn main() {}
diff --git a/src/test/ui/or-patterns/issue-69875-should-have-been-expanded-earlier-non-exhaustive.rs b/src/test/ui/or-patterns/issue-69875-should-have-been-expanded-earlier-non-exhaustive.rs
new file mode 100644
index 00000000000..59533cefea6
--- /dev/null
+++ b/src/test/ui/or-patterns/issue-69875-should-have-been-expanded-earlier-non-exhaustive.rs
@@ -0,0 +1,9 @@
+#![feature(or_patterns)]
+
+fn main() {
+    let 0 | (1 | 2) = 0; //~ ERROR refutable pattern in local binding
+    match 0 {
+        //~^ ERROR non-exhaustive patterns
+        0 | (1 | 2) => {}
+    }
+}
diff --git a/src/test/ui/or-patterns/issue-69875-should-have-been-expanded-earlier-non-exhaustive.stderr b/src/test/ui/or-patterns/issue-69875-should-have-been-expanded-earlier-non-exhaustive.stderr
new file mode 100644
index 00000000000..58286e87869
--- /dev/null
+++ b/src/test/ui/or-patterns/issue-69875-should-have-been-expanded-earlier-non-exhaustive.stderr
@@ -0,0 +1,25 @@
+error[E0005]: refutable pattern in local binding: `std::i32::MIN..=-1i32` and `3i32..=std::i32::MAX` not covered
+  --> $DIR/issue-69875-should-have-been-expanded-earlier-non-exhaustive.rs:4:9
+   |
+LL |     let 0 | (1 | 2) = 0;
+   |         ^^^^^^^^^^^ patterns `std::i32::MIN..=-1i32` and `3i32..=std::i32::MAX` not covered
+   |
+   = note: `let` bindings require an "irrefutable pattern", like a `struct` or an `enum` with only one variant
+   = note: for more information, visit https://doc.rust-lang.org/book/ch18-02-refutability.html
+help: you might want to use `if let` to ignore the variant that isn't matched
+   |
+LL |     if let 0 | (1 | 2) = 0 { /* */ }
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0004]: non-exhaustive patterns: `std::i32::MIN..=-1i32` and `3i32..=std::i32::MAX` not covered
+  --> $DIR/issue-69875-should-have-been-expanded-earlier-non-exhaustive.rs:5:11
+   |
+LL |     match 0 {
+   |           ^ patterns `std::i32::MIN..=-1i32` and `3i32..=std::i32::MAX` not covered
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0004, E0005.
+For more information about an error, try `rustc --explain E0004`.
diff --git a/src/test/ui/or-patterns/issue-69875-should-have-been-expanded-earlier.rs b/src/test/ui/or-patterns/issue-69875-should-have-been-expanded-earlier.rs
new file mode 100644
index 00000000000..1de563dedbf
--- /dev/null
+++ b/src/test/ui/or-patterns/issue-69875-should-have-been-expanded-earlier.rs
@@ -0,0 +1,9 @@
+// check-pass
+
+#![feature(or_patterns)]
+
+fn main() {
+    let 0 | (1 | _) = 0;
+    if let 0 | (1 | 2) = 0 {}
+    if let x @ 0 | x @ (1 | 2) = 0 {}
+}