Auto merge of #77172 - jonas-schievink:rollup-a041rou, r=jonas-schievink

Rollup of 15 pull requests

Successful merges:

 - #75438 (Use adaptive SVG favicon for rustdoc like other rust sites)
 - #76304 (Make delegation methods of `std::net::IpAddr` unstably const)
 - #76724 (Allow a unique name to be assigned to dataflow graphviz output)
 - #76978 (Documented From impls in std/sync/mpsc/mod.rs)
 - #77044 (Liballoc bench vec use mem take not replace)
 - #77050 (Typo fix: "satsify" -> "satisfy")
 - #77074 (add array::from_ref)
 - #77078 (Don't use an if guard to check equality with a constant)
 - #77079 (Use `Self` in docs when possible)
 - #77081 (Merge two almost identical match arms)
 - #77121 (Updated html_root_url for compiler crates)
 - #77136 (Suggest `const_mut_refs`, not `const_fn` for mutable references in `const fn`)
 - #77160 (Suggest `const_fn_transmute`, not `const_fn`)
 - #77164 (Remove workaround for deref issue that no longer exists.)
 - #77165 (Followup to #76673)

Failed merges:

r? `@ghost`

20 files changed, 132 insertions, 91 deletions

diff --git a/src/librustdoc/html/layout.rs b/src/librustdoc/html/layout.rs
index 287c85b8c22..7239b3c5ba2 100644
--- a/src/librustdoc/html/layout.rs
+++ b/src/librustdoc/html/layout.rs
@@ -158,7 +158,9 @@ pub fn render<T: Print, S: Print>(
         keywords = page.keywords,
         favicon = if layout.favicon.is_empty() {
             format!(
-                r#"<link rel="shortcut icon" href="{static_root_path}favicon{suffix}.ico">"#,
+                r##"<link rel="icon" type="image/svg+xml" href="{static_root_path}favicon{suffix}.svg">
+<link rel="alternate icon" type="image/png" href="{static_root_path}favicon-16x16{suffix}.png">
+<link rel="alternate icon" type="image/png" href="{static_root_path}favicon-32x32{suffix}.png">"##,
                 static_root_path = static_root_path,
                 suffix = page.resource_suffix
             )
diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index f095f67b54c..8b5ba7a239c 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -754,7 +754,9 @@ fn write_shared(
         write(cx.path("rust-logo.png"), static_files::RUST_LOGO)?;
     }
     if (*cx.shared).layout.favicon.is_empty() {
-        write(cx.path("favicon.ico"), static_files::RUST_FAVICON)?;
+        write(cx.path("favicon.svg"), static_files::RUST_FAVICON_SVG)?;
+        write(cx.path("favicon-16x16.png"), static_files::RUST_FAVICON_PNG_16)?;
+        write(cx.path("favicon-32x32.png"), static_files::RUST_FAVICON_PNG_32)?;
     }
     write(cx.path("brush.svg"), static_files::BRUSH_SVG)?;
     write(cx.path("wheel.svg"), static_files::WHEEL_SVG)?;
diff --git a/src/librustdoc/html/static/favicon-16x16.png b/src/librustdoc/html/static/favicon-16x16.png
new file mode 100644
index 00000000000..7cfe6c13550
--- /dev/null
+++ b/src/librustdoc/html/static/favicon-16x16.png
Binary files differdiff --git a/src/librustdoc/html/static/favicon-32x32.png b/src/librustdoc/html/static/favicon-32x32.png
new file mode 100644
index 00000000000..5109c1de8be
--- /dev/null
+++ b/src/librustdoc/html/static/favicon-32x32.png
Binary files differdiff --git a/src/librustdoc/html/static/favicon.ico b/src/librustdoc/html/static/favicon.ico
deleted file mode 100644
index b8ad23769ac..00000000000
--- a/src/librustdoc/html/static/favicon.ico
+++ /dev/null
Binary files differdiff --git a/src/librustdoc/html/static/favicon.svg b/src/librustdoc/html/static/favicon.svg
new file mode 100644
index 00000000000..8b34b511989
--- /dev/null
+++ b/src/librustdoc/html/static/favicon.svg
@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?><!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"><svg width="100%" height="100%" viewBox="0 0 32 32" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" xml:space="preserve" xmlns:serif="http://www.serif.com/" style="fill-rule:evenodd;clip-rule:evenodd;stroke-linecap:round;stroke-linejoin:round;">
+<defs>
+  <style type="text/css"><![CDATA[
+    #logo {
+      fill-rule: nonzero;
+    }
+    #logo-teeth {
+      stroke: #000000;
+      stroke-width: 0.92px;
+    }
+    @media (prefers-color-scheme: dark) {
+      #logo {
+        fill: #FFFFFF;
+        fill-rule: nonzero;
+      }
+      #logo-teeth {
+        fill: #FFFFFF;
+        stroke: #FFFFFF;
+        stroke-width: 0.92px;
+      }
+    }
+  ]]></style>
+</defs>
+<path id="logo" d="M15.993,1.54c-7.972,0 -14.461,6.492 -14.461,14.462c0,7.969 6.492,14.461 14.461,14.461c7.97,0 14.462,-6.492 14.462,-14.461c0,-7.97 -6.492,-14.462 -14.462,-14.462Zm-0.021,1.285c0.511,0.013 0.924,0.439 0.924,0.951c0,0.522 -0.43,0.952 -0.952,0.952c-0.522,0 -0.951,-0.43 -0.951,-0.952c0,0 0,0 0,0c0,-0.522 0.429,-0.952 0.951,-0.952c0.01,0 0.019,0.001 0.028,0.001Zm2.178,1.566c3.379,0.633 6.313,2.723 8.016,5.709l-1.123,2.533c-0.193,0.438 0.006,0.952 0.44,1.147l2.16,0.958c0.067,0.675 0.076,1.355 0.025,2.031l-1.202,0c-0.12,0 -0.169,0.08 -0.169,0.196l0,0.551c0,1.297 -0.731,1.582 -1.373,1.652c-0.612,0.07 -1.288,-0.257 -1.374,-0.63c-0.361,-2.029 -0.961,-2.46 -1.909,-3.21c1.178,-0.746 2.401,-1.85 2.401,-3.325c0,-1.594 -1.092,-2.597 -1.835,-3.09c-1.046,-0.688 -2.203,-0.826 -2.515,-0.826l-12.421,0c1.717,-1.918 4.02,-3.218 6.55,-3.696l1.466,1.536c0.33,0.346 0.878,0.361 1.223,0.028l1.64,-1.564Zm-13.522,7.043c0.511,0.015 0.924,0.44 0.924,0.951c0,0.522 -0.43,0.952 -0.952,0.952c-0.522,0 -0.951,-0.43 -0.951,-0.952c0,0 0,0 0,0c0,-0.522 0.429,-0.951 0.951,-0.951c0.009,0 0.019,0 0.028,0Zm22.685,0.043c0.511,0.015 0.924,0.44 0.924,0.951c0,0.522 -0.43,0.952 -0.952,0.952c-0.522,0 -0.951,-0.43 -0.951,-0.952c0,0 0,0 0,0c0,-0.522 0.429,-0.952 0.951,-0.952c0.01,0 0.019,0 0.028,0.001Zm-20.892,0.153l1.658,0l0,7.477l-3.347,0c-0.414,-1.452 -0.542,-2.97 -0.38,-4.47l2.05,-0.912c0.438,-0.195 0.637,-0.706 0.441,-1.144l-0.422,-0.951Zm6.92,0.079l3.949,0c0.205,0 1.441,0.236 1.441,1.163c0,0.768 -0.948,1.043 -1.728,1.043l-3.665,0l0.003,-2.206Zm0,5.373l3.026,0c0.275,0 1.477,0.079 1.86,1.615c0.119,0.471 0.385,2.007 0.566,2.499c0.18,0.551 0.911,1.652 1.691,1.652l4.938,0c-0.331,0.444 -0.693,0.863 -1.083,1.255l-2.01,-0.432c-0.468,-0.101 -0.93,0.199 -1.031,0.667l-0.477,2.228c-3.104,1.406 -6.672,1.389 -9.762,-0.046l-0.478,-2.228c-0.101,-0.468 -0.56,-0.767 -1.028,-0.667l-1.967,0.423c-0.365,-0.377 -0.704,-0.778 -1.016,-1.2l9.567,0c0.107,0 0.181,-0.018 0.181,-0.119l0,-3.384c0,-0.097 -0.074,-0.119 -0.181,-0.119l-2.799,0l0.003,-2.144Zm-4.415,7.749c0.512,0.015 0.924,0.44 0.924,0.951c0,0.522 -0.429,0.952 -0.951,0.952c-0.522,0 -0.952,-0.43 -0.952,-0.952c0,0 0,0 0,0c0,-0.522 0.43,-0.952 0.952,-0.952c0.009,0 0.018,0.001 0.027,0.001Zm14.089,0.043c0.511,0.015 0.924,0.439 0.923,0.951c0,0.522 -0.429,0.952 -0.951,0.952c-0.522,0 -0.951,-0.43 -0.951,-0.952c0,0 0,0 0,0c0,-0.522 0.429,-0.952 0.951,-0.952c0.009,0 0.018,0 0.028,0.001Z"/><path id="logo-teeth" d="M29.647,16.002c0,7.49 -6.163,13.653 -13.654,13.653c-7.49,0 -13.654,-6.163 -13.654,-13.653c0,-7.491 6.164,-13.654 13.654,-13.654c7.491,0 13.654,6.163 13.654,13.654Zm-0.257,-1.319l2.13,1.319l-2.13,1.318l1.83,1.71l-2.344,0.878l1.463,2.035l-2.475,0.404l1.04,2.282l-2.506,-0.089l0.575,2.442l-2.441,-0.576l0.089,2.506l-2.283,-1.04l-0.403,2.475l-2.035,-1.462l-0.878,2.343l-1.71,-1.829l-1.319,2.129l-1.318,-2.129l-1.71,1.829l-0.878,-2.343l-2.035,1.462l-0.404,-2.475l-2.282,1.04l0.089,-2.506l-2.442,0.576l0.575,-2.442l-2.505,0.089l1.04,-2.282l-2.475,-0.404l1.462,-2.035l-2.343,-0.878l1.829,-1.71l-2.129,-1.318l2.129,-1.319l-1.829,-1.71l2.343,-0.878l-1.462,-2.035l2.475,-0.404l-1.04,-2.282l2.505,0.089l-0.575,-2.441l2.442,0.575l-0.089,-2.506l2.282,1.04l0.404,-2.475l2.035,1.463l0.878,-2.344l1.71,1.83l1.318,-2.13l1.319,2.13l1.71,-1.83l0.878,2.344l2.035,-1.463l0.403,2.475l2.283,-1.04l-0.089,2.506l2.441,-0.575l-0.575,2.441l2.506,-0.089l-1.04,2.282l2.475,0.404l-1.463,2.035l2.344,0.878l-1.83,1.71Z"/></svg>
diff --git a/src/librustdoc/html/static_files.rs b/src/librustdoc/html/static_files.rs
index 6bd7e53cdfb..213c7f3aab8 100644
--- a/src/librustdoc/html/static_files.rs
+++ b/src/librustdoc/html/static_files.rs
@@ -53,8 +53,10 @@ pub static LICENSE_MIT: &[u8] = include_bytes!("static/LICENSE-MIT.txt");
 
 /// The contents of `rust-logo.png`, the default icon of the documentation.
 pub static RUST_LOGO: &[u8] = include_bytes!("static/rust-logo.png");
-/// The contents of `favicon.ico`, the default favicon of the documentation.
-pub static RUST_FAVICON: &[u8] = include_bytes!("static/favicon.ico");
+/// The default documentation favicons (SVG and PNG fallbacks)
+pub static RUST_FAVICON_SVG: &[u8] = include_bytes!("static/favicon.svg");
+pub static RUST_FAVICON_PNG_16: &[u8] = include_bytes!("static/favicon-16x16.png");
+pub static RUST_FAVICON_PNG_32: &[u8] = include_bytes!("static/favicon-32x32.png");
 
 /// The built-in themes given to every documentation site.
 pub mod themes {
diff --git a/src/test/ui/consts/const-mut-refs/feature-gate-const_mut_refs.rs b/src/test/ui/consts/const-mut-refs/feature-gate-const_mut_refs.rs
index f31543af590..ce9be4ac5c2 100644
--- a/src/test/ui/consts/const-mut-refs/feature-gate-const_mut_refs.rs
+++ b/src/test/ui/consts/const-mut-refs/feature-gate-const_mut_refs.rs
@@ -2,7 +2,7 @@ fn main() {
     foo(&mut 5);
 }
 
-const fn foo(x: &mut i32) -> i32 { //~ ERROR mutable references in const fn
+const fn foo(x: &mut i32) -> i32 { //~ ERROR mutable references
     *x + 1
 
 }
diff --git a/src/test/ui/consts/const-mut-refs/feature-gate-const_mut_refs.stderr b/src/test/ui/consts/const-mut-refs/feature-gate-const_mut_refs.stderr
index 83e050c7a5c..3f9bd37053a 100644
--- a/src/test/ui/consts/const-mut-refs/feature-gate-const_mut_refs.stderr
+++ b/src/test/ui/consts/const-mut-refs/feature-gate-const_mut_refs.stderr
@@ -1,12 +1,12 @@
-error[E0723]: mutable references in const fn are unstable
+error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/feature-gate-const_mut_refs.rs:5:14
    |
 LL | const fn foo(x: &mut i32) -> i32 {
    |              ^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
+   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0723`.
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/consts/const_let_assign3.stderr b/src/test/ui/consts/const_let_assign3.stderr
index 785d9c8c2a5..15badea0037 100644
--- a/src/test/ui/consts/const_let_assign3.stderr
+++ b/src/test/ui/consts/const_let_assign3.stderr
@@ -1,11 +1,11 @@
-error[E0723]: mutable references in const fn are unstable
+error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/const_let_assign3.rs:8:18
    |
 LL |     const fn foo(&mut self, x: u32) {
    |                  ^^^^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
+   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
 error[E0764]: mutable references are not allowed in constants
   --> $DIR/const_let_assign3.rs:16:5
@@ -29,5 +29,5 @@ LL |     *y = 42;
 
 error: aborting due to 4 previous errors
 
-Some errors have detailed explanations: E0019, E0723, E0764.
+Some errors have detailed explanations: E0019, E0658, E0764.
 For more information about an error, try `rustc --explain E0019`.
diff --git a/src/test/ui/consts/min_const_fn/min_const_fn.rs b/src/test/ui/consts/min_const_fn/min_const_fn.rs
index 5dd70acb6ff..336d754b06a 100644
--- a/src/test/ui/consts/min_const_fn/min_const_fn.rs
+++ b/src/test/ui/consts/min_const_fn/min_const_fn.rs
@@ -37,26 +37,26 @@ impl<T> Foo<T> {
     const fn into_inner(self) -> T { self.0 } //~ destructors cannot be evaluated
     const fn get(&self) -> &T { &self.0 }
     const fn get_mut(&mut self) -> &mut T { &mut self.0 }
-    //~^ mutable references in const fn are unstable
+    //~^ mutable references
 }
 impl<'a, T> Foo<T> {
     const fn new_lt(t: T) -> Self { Foo(t) }
     const fn into_inner_lt(self) -> T { self.0 } //~ destructors cannot be evaluated
     const fn get_lt(&'a self) -> &T { &self.0 }
     const fn get_mut_lt(&'a mut self) -> &mut T { &mut self.0 }
-    //~^ mutable references in const fn are unstable
+    //~^ mutable references
 }
 impl<T: Sized> Foo<T> {
     const fn new_s(t: T) -> Self { Foo(t) }
     const fn into_inner_s(self) -> T { self.0 } //~ ERROR destructors
     const fn get_s(&self) -> &T { &self.0 }
     const fn get_mut_s(&mut self) -> &mut T { &mut self.0 }
-    //~^ mutable references in const fn are unstable
+    //~^ mutable references
 }
 impl<T: ?Sized> Foo<T> {
     const fn get_sq(&self) -> &T { &self.0 }
     const fn get_mut_sq(&mut self) -> &mut T { &mut self.0 }
-    //~^ mutable references in const fn are unstable
+    //~^ mutable references
 }
 
 
@@ -99,7 +99,7 @@ const fn foo30_2_with_unsafe(x: *mut u32) -> usize { unsafe { x as usize } }
 //~^ ERROR casting pointers to integers
 const fn foo30_6() -> bool { let x = true; x }
 const fn inc(x: &mut i32) { *x += 1 }
-//~^ ERROR mutable references in const fn are unstable
+//~^ ERROR mutable references
 
 // ok
 const fn foo36(a: bool, b: bool) -> bool { a && b }
diff --git a/src/test/ui/consts/min_const_fn/min_const_fn.stderr b/src/test/ui/consts/min_const_fn/min_const_fn.stderr
index d4498f061c6..c96500e38ec 100644
--- a/src/test/ui/consts/min_const_fn/min_const_fn.stderr
+++ b/src/test/ui/consts/min_const_fn/min_const_fn.stderr
@@ -6,14 +6,14 @@ LL |     const fn into_inner(self) -> T { self.0 }
    |                         |
    |                         constant functions cannot evaluate destructors
 
-error[E0723]: mutable references in const fn are unstable
+error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/min_const_fn.rs:39:36
    |
 LL |     const fn get_mut(&mut self) -> &mut T { &mut self.0 }
    |                                    ^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
+   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
 error[E0493]: destructors cannot be evaluated at compile-time
   --> $DIR/min_const_fn.rs:44:28
@@ -23,14 +23,14 @@ LL |     const fn into_inner_lt(self) -> T { self.0 }
    |                            |
    |                            constant functions cannot evaluate destructors
 
-error[E0723]: mutable references in const fn are unstable
+error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/min_const_fn.rs:46:42
    |
 LL |     const fn get_mut_lt(&'a mut self) -> &mut T { &mut self.0 }
    |                                          ^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
+   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
 error[E0493]: destructors cannot be evaluated at compile-time
   --> $DIR/min_const_fn.rs:51:27
@@ -40,23 +40,23 @@ LL |     const fn into_inner_s(self) -> T { self.0 }
    |                           |
    |                           constant functions cannot evaluate destructors
 
-error[E0723]: mutable references in const fn are unstable
+error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/min_const_fn.rs:53:38
    |
 LL |     const fn get_mut_s(&mut self) -> &mut T { &mut self.0 }
    |                                      ^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
+   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
-error[E0723]: mutable references in const fn are unstable
+error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/min_const_fn.rs:58:39
    |
 LL |     const fn get_mut_sq(&mut self) -> &mut T { &mut self.0 }
    |                                       ^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
+   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
 error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
   --> $DIR/min_const_fn.rs:76:16
@@ -164,14 +164,14 @@ LL | const fn foo30_2_with_unsafe(x: *mut u32) -> usize { unsafe { x as usize }
    = note: see issue #51910 <https://github.com/rust-lang/rust/issues/51910> for more information
    = help: add `#![feature(const_raw_ptr_to_usize_cast)]` to the crate attributes to enable
 
-error[E0723]: mutable references in const fn are unstable
+error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/min_const_fn.rs:101:14
    |
 LL | const fn inc(x: &mut i32) { *x += 1 }
    |              ^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
+   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
 error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
   --> $DIR/min_const_fn.rs:110:6
diff --git a/src/test/ui/consts/min_const_fn/mutable_borrow.rs b/src/test/ui/consts/min_const_fn/mutable_borrow.rs
index 89acfea6ed8..580b1d50f77 100644
--- a/src/test/ui/consts/min_const_fn/mutable_borrow.rs
+++ b/src/test/ui/consts/min_const_fn/mutable_borrow.rs
@@ -1,6 +1,6 @@
 const fn mutable_ref_in_const() -> u8 {
     let mut a = 0;
-    let b = &mut a; //~ ERROR mutable references in const fn
+    let b = &mut a; //~ ERROR mutable references
     *b
 }
 
@@ -9,7 +9,7 @@ struct X;
 impl X {
     const fn inherent_mutable_ref_in_const() -> u8 {
         let mut a = 0;
-        let b = &mut a; //~ ERROR mutable references in const fn
+        let b = &mut a; //~ ERROR mutable references
         *b
     }
 }
diff --git a/src/test/ui/consts/min_const_fn/mutable_borrow.stderr b/src/test/ui/consts/min_const_fn/mutable_borrow.stderr
index f5a3c168a86..4e5cdbb18aa 100644
--- a/src/test/ui/consts/min_const_fn/mutable_borrow.stderr
+++ b/src/test/ui/consts/min_const_fn/mutable_borrow.stderr
@@ -1,21 +1,21 @@
-error[E0723]: mutable references in const fn are unstable
+error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/mutable_borrow.rs:3:9
    |
 LL |     let b = &mut a;
    |         ^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
+   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
-error[E0723]: mutable references in const fn are unstable
+error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/mutable_borrow.rs:12:13
    |
 LL |         let b = &mut a;
    |             ^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
+   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
 error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0723`.
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/feature-gates/feature-gate-const_fn_transmute.rs b/src/test/ui/feature-gates/feature-gate-const_fn_transmute.rs
index 981680b5d1f..9007e501bc2 100644
--- a/src/test/ui/feature-gates/feature-gate-const_fn_transmute.rs
+++ b/src/test/ui/feature-gates/feature-gate-const_fn_transmute.rs
@@ -6,33 +6,33 @@ struct Foo(u32);
 const TRANSMUTED_U32: u32 = unsafe { mem::transmute(Foo(3)) };
 
 const fn transmute_fn() -> u32 { unsafe { mem::transmute(Foo(3)) } }
-//~^ ERROR can only call `transmute` from const items, not `const fn`
+//~^ ERROR `transmute`
 
 const fn transmute_fn_intrinsic() -> u32 { unsafe { std::intrinsics::transmute(Foo(3)) } }
-//~^ ERROR can only call `transmute` from const items, not `const fn`
+//~^ ERROR `transmute`
 
 const fn transmute_fn_core_intrinsic() -> u32 { unsafe { core::intrinsics::transmute(Foo(3)) } }
-//~^ ERROR can only call `transmute` from const items, not `const fn`
+//~^ ERROR `transmute`
 
 const unsafe fn unsafe_transmute_fn() -> u32 { mem::transmute(Foo(3)) }
-//~^ ERROR can only call `transmute` from const items, not `const fn`
+//~^ ERROR `transmute`
 
 const unsafe fn unsafe_transmute_fn_intrinsic() -> u32 { std::intrinsics::transmute(Foo(3)) }
-//~^ ERROR can only call `transmute` from const items, not `const fn`
+//~^ ERROR `transmute`
 
 const unsafe fn unsafe_transmute_fn_core_intrinsic() -> u32 { core::intrinsics::transmute(Foo(3)) }
-//~^ ERROR can only call `transmute` from const items, not `const fn`
+//~^ ERROR `transmute`
 
 const fn safe_transmute_fn() -> u32 { mem::transmute(Foo(3)) }
-//~^ ERROR can only call `transmute` from const items, not `const fn`
+//~^ ERROR `transmute`
 //~| ERROR call to unsafe function is unsafe and requires unsafe function or block
 
 const fn safe_transmute_fn_intrinsic() -> u32 { std::intrinsics::transmute(Foo(3)) }
-//~^ ERROR can only call `transmute` from const items, not `const fn`
+//~^ ERROR `transmute`
 //~| ERROR call to unsafe function is unsafe and requires unsafe function or block
 
 const fn safe_transmute_fn_core_intrinsic() -> u32 { core::intrinsics::transmute(Foo(3)) }
-//~^ ERROR can only call `transmute` from const items, not `const fn`
+//~^ ERROR `transmute`
 //~| ERROR call to unsafe function is unsafe and requires unsafe function or block
 
 fn main() {}
diff --git a/src/test/ui/feature-gates/feature-gate-const_fn_transmute.stderr b/src/test/ui/feature-gates/feature-gate-const_fn_transmute.stderr
index 44430fd577d..08ba14dc40e 100644
--- a/src/test/ui/feature-gates/feature-gate-const_fn_transmute.stderr
+++ b/src/test/ui/feature-gates/feature-gate-const_fn_transmute.stderr
@@ -1,83 +1,92 @@
-error[E0723]: can only call `transmute` from const items, not `const fn`
+error[E0658]: `transmute` is not allowed in constant functions
   --> $DIR/feature-gate-const_fn_transmute.rs:8:43
    |
 LL | const fn transmute_fn() -> u32 { unsafe { mem::transmute(Foo(3)) } }
    |                                           ^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #53605 <https://github.com/rust-lang/rust/issues/53605> for more information
+   = help: add `#![feature(const_fn_transmute)]` to the crate attributes to enable
+   = note: `transmute` is only allowed in constants and statics for now
 
-error[E0723]: can only call `transmute` from const items, not `const fn`
+error[E0658]: `transmute` is not allowed in constant functions
   --> $DIR/feature-gate-const_fn_transmute.rs:11:53
    |
 LL | const fn transmute_fn_intrinsic() -> u32 { unsafe { std::intrinsics::transmute(Foo(3)) } }
    |                                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #53605 <https://github.com/rust-lang/rust/issues/53605> for more information
+   = help: add `#![feature(const_fn_transmute)]` to the crate attributes to enable
+   = note: `transmute` is only allowed in constants and statics for now
 
-error[E0723]: can only call `transmute` from const items, not `const fn`
+error[E0658]: `transmute` is not allowed in constant functions
   --> $DIR/feature-gate-const_fn_transmute.rs:14:58
    |
 LL | const fn transmute_fn_core_intrinsic() -> u32 { unsafe { core::intrinsics::transmute(Foo(3)) } }
    |                                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #53605 <https://github.com/rust-lang/rust/issues/53605> for more information
+   = help: add `#![feature(const_fn_transmute)]` to the crate attributes to enable
+   = note: `transmute` is only allowed in constants and statics for now
 
-error[E0723]: can only call `transmute` from const items, not `const fn`
+error[E0658]: `transmute` is not allowed in constant functions
   --> $DIR/feature-gate-const_fn_transmute.rs:17:48
    |
 LL | const unsafe fn unsafe_transmute_fn() -> u32 { mem::transmute(Foo(3)) }
    |                                                ^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #53605 <https://github.com/rust-lang/rust/issues/53605> for more information
+   = help: add `#![feature(const_fn_transmute)]` to the crate attributes to enable
+   = note: `transmute` is only allowed in constants and statics for now
 
-error[E0723]: can only call `transmute` from const items, not `const fn`
+error[E0658]: `transmute` is not allowed in constant functions
   --> $DIR/feature-gate-const_fn_transmute.rs:20:58
    |
 LL | const unsafe fn unsafe_transmute_fn_intrinsic() -> u32 { std::intrinsics::transmute(Foo(3)) }
    |                                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #53605 <https://github.com/rust-lang/rust/issues/53605> for more information
+   = help: add `#![feature(const_fn_transmute)]` to the crate attributes to enable
+   = note: `transmute` is only allowed in constants and statics for now
 
-error[E0723]: can only call `transmute` from const items, not `const fn`
+error[E0658]: `transmute` is not allowed in constant functions
   --> $DIR/feature-gate-const_fn_transmute.rs:23:63
    |
 LL | const unsafe fn unsafe_transmute_fn_core_intrinsic() -> u32 { core::intrinsics::transmute(Foo(3)) }
    |                                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #53605 <https://github.com/rust-lang/rust/issues/53605> for more information
+   = help: add `#![feature(const_fn_transmute)]` to the crate attributes to enable
+   = note: `transmute` is only allowed in constants and statics for now
 
-error[E0723]: can only call `transmute` from const items, not `const fn`
+error[E0658]: `transmute` is not allowed in constant functions
   --> $DIR/feature-gate-const_fn_transmute.rs:26:39
    |
 LL | const fn safe_transmute_fn() -> u32 { mem::transmute(Foo(3)) }
    |                                       ^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #53605 <https://github.com/rust-lang/rust/issues/53605> for more information
+   = help: add `#![feature(const_fn_transmute)]` to the crate attributes to enable
+   = note: `transmute` is only allowed in constants and statics for now
 
-error[E0723]: can only call `transmute` from const items, not `const fn`
+error[E0658]: `transmute` is not allowed in constant functions
   --> $DIR/feature-gate-const_fn_transmute.rs:30:49
    |
 LL | const fn safe_transmute_fn_intrinsic() -> u32 { std::intrinsics::transmute(Foo(3)) }
    |                                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #53605 <https://github.com/rust-lang/rust/issues/53605> for more information
+   = help: add `#![feature(const_fn_transmute)]` to the crate attributes to enable
+   = note: `transmute` is only allowed in constants and statics for now
 
-error[E0723]: can only call `transmute` from const items, not `const fn`
+error[E0658]: `transmute` is not allowed in constant functions
   --> $DIR/feature-gate-const_fn_transmute.rs:34:54
    |
 LL | const fn safe_transmute_fn_core_intrinsic() -> u32 { core::intrinsics::transmute(Foo(3)) }
    |                                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #53605 <https://github.com/rust-lang/rust/issues/53605> for more information
+   = help: add `#![feature(const_fn_transmute)]` to the crate attributes to enable
+   = note: `transmute` is only allowed in constants and statics for now
 
 error[E0133]: call to unsafe function is unsafe and requires unsafe function or block
   --> $DIR/feature-gate-const_fn_transmute.rs:26:39
@@ -105,5 +114,5 @@ LL | const fn safe_transmute_fn_core_intrinsic() -> u32 { core::intrinsics::tran
 
 error: aborting due to 12 previous errors
 
-Some errors have detailed explanations: E0133, E0723.
+Some errors have detailed explanations: E0133, E0658.
 For more information about an error, try `rustc --explain E0133`.
diff --git a/src/test/ui/internal/internal-unstable-const.rs b/src/test/ui/internal/internal-unstable-const.rs
index b923bc22f6e..554c67be4e0 100644
--- a/src/test/ui/internal/internal-unstable-const.rs
+++ b/src/test/ui/internal/internal-unstable-const.rs
@@ -8,7 +8,7 @@
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_const_stable(feature = "rust1", since = "1.0.0")]
 pub const fn foo() -> i32 {
-    unsafe { std::mem::transmute(4u32) } //~ ERROR can only call `transmute` from const items
+    unsafe { std::mem::transmute(4u32) } //~ ERROR `transmute`
 }
 
 fn main() {}
diff --git a/src/test/ui/internal/internal-unstable-const.stderr b/src/test/ui/internal/internal-unstable-const.stderr
index 9626df23ec3..adfb8dc3691 100644
--- a/src/test/ui/internal/internal-unstable-const.stderr
+++ b/src/test/ui/internal/internal-unstable-const.stderr
@@ -1,12 +1,13 @@
-error[E0723]: can only call `transmute` from const items, not `const fn`
+error[E0658]: `transmute` is not allowed in constant functions
   --> $DIR/internal-unstable-const.rs:11:14
    |
 LL |     unsafe { std::mem::transmute(4u32) }
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #53605 <https://github.com/rust-lang/rust/issues/53605> for more information
+   = help: add `#![feature(const_fn_transmute)]` to the crate attributes to enable
+   = note: `transmute` is only allowed in constants and statics for now
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0723`.
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/unsafe/ranged_ints2_const.stderr b/src/test/ui/unsafe/ranged_ints2_const.stderr
index d508d07791d..1a6bcd36ee1 100644
--- a/src/test/ui/unsafe/ranged_ints2_const.stderr
+++ b/src/test/ui/unsafe/ranged_ints2_const.stderr
@@ -1,20 +1,20 @@
-error[E0723]: mutable references in const fn are unstable
+error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/ranged_ints2_const.rs:11:9
    |
 LL |     let y = &mut x.0;
    |         ^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
+   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
-error[E0723]: mutable references in const fn are unstable
+error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/ranged_ints2_const.rs:18:9
    |
 LL |     let y = unsafe { &mut x.0 };
    |         ^
    |
-   = note: see issue #57563 <https://github.com/rust-lang/rust/issues/57563> for more information
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
+   = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
+   = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
 error[E0133]: mutation of layout constrained field is unsafe and requires unsafe function or block
   --> $DIR/ranged_ints2_const.rs:11:13
@@ -26,5 +26,5 @@ LL |     let y = &mut x.0;
 
 error: aborting due to 3 previous errors
 
-Some errors have detailed explanations: E0133, E0723.
+Some errors have detailed explanations: E0133, E0658.
 For more information about an error, try `rustc --explain E0133`.
diff --git a/src/tools/clippy/clippy_lints/src/redundant_clone.rs b/src/tools/clippy/clippy_lints/src/redundant_clone.rs
index 57a45e628db..1615f192370 100644
--- a/src/tools/clippy/clippy_lints/src/redundant_clone.rs
+++ b/src/tools/clippy/clippy_lints/src/redundant_clone.rs
@@ -87,6 +87,7 @@ impl<'tcx> LateLintPass<'tcx> for RedundantClone {
 
         let maybe_storage_live_result = MaybeStorageLive
             .into_engine(cx.tcx, mir, def_id.to_def_id())
+            .pass_name("redundant_clone")
             .iterate_to_fixpoint()
             .into_results_cursor(mir);
         let mut possible_borrower = {