Auto merge of #93119 - matthiaskrgr:rollup-ku3cn5j, r=matthiaskrgr

Rollup of 13 pull requests

Successful merges:

 - #89747 (Add MaybeUninit::(slice_)as_bytes(_mut))
 - #89764 (Fix variant index / discriminant confusion in uninhabited enum branching)
 - #91606 (Stabilize `-Z print-link-args` as `--print link-args`)
 - #91694 (rustdoc: decouple stability and const-stability)
 - #92183 (Point at correct argument when async fn output type lifetime disagrees with signature)
 - #92582 (improve `_` constants in item signature handling)
 - #92680 (intra-doc: Use the impl's assoc item where possible)
 - #92704 (Change lint message to be stronger for &T -> &mut T transmute)
 - #92861 (Rustdoc mobile: put out-of-band info on its own line)
 - #92992 (Help optimize out backtraces when disabled)
 - #93038 (Fix star handling in block doc comments)
 - #93108 (:arrow_up: rust-analyzer)
 - #93112 (Fix CVE-2022-21658)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

2 files changed, 75 insertions, 45 deletions

diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index 29a793f3110..8badce8226f 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -799,6 +799,20 @@ fn assoc_type(
     }
 }
 
+/// Writes a span containing the versions at which an item became stable and/or const-stable. For
+/// example, if the item became stable at 1.0.0, and const-stable at 1.45.0, this function would
+/// write a span containing "1.0.0 (const: 1.45.0)".
+///
+/// Returns `true` if a stability annotation was rendered.
+///
+/// Stability and const-stability are considered separately. If the item is unstable, no version
+/// will be written. If the item is const-unstable, "const: unstable" will be appended to the
+/// span, with a link to the tracking issue if present. If an item's stability or const-stability
+/// version matches the version of its enclosing item, that version will be omitted.
+///
+/// Note that it is possible for an unstable function to be const-stable. In that case, the span
+/// will include the const-stable version, but no stable version will be emitted, as a natural
+/// consequence of the above rules.
 fn render_stability_since_raw(
     w: &mut Buffer,
     ver: Option<Symbol>,
@@ -806,51 +820,56 @@ fn render_stability_since_raw(
     containing_ver: Option<Symbol>,
     containing_const_ver: Option<Symbol>,
 ) -> bool {
-    let ver = ver.filter(|inner| !inner.is_empty());
+    let stable_version = ver.filter(|inner| !inner.is_empty() && Some(*inner) != containing_ver);
 
-    match (ver, const_stability) {
-        // stable and const stable
-        (Some(v), Some(ConstStability { level: StabilityLevel::Stable { since }, .. }))
+    let mut title = String::new();
+    let mut stability = String::new();
+
+    if let Some(ver) = stable_version {
+        stability.push_str(&ver.as_str());
+        title.push_str(&format!("Stable since Rust version {}", ver));
+    }
+
+    let const_title_and_stability = match const_stability {
+        Some(ConstStability { level: StabilityLevel::Stable { since }, .. })
             if Some(since) != containing_const_ver =>
         {
-            write!(
-                w,
-                "<span class=\"since\" title=\"Stable since Rust version {0}, const since {1}\">{0} (const: {1})</span>",
-                v, since
-            );
+            Some((format!("const since {}", since), format!("const: {}", since)))
         }
-        // stable and const unstable
-        (
-            Some(v),
-            Some(ConstStability { level: StabilityLevel::Unstable { issue, .. }, feature, .. }),
-        ) => {
-            write!(
-                w,
-                "<span class=\"since\" title=\"Stable since Rust version {0}, const unstable\">{0} (const: ",
-                v
-            );
-            if let Some(n) = issue {
-                write!(
-                    w,
-                    "<a href=\"https://github.com/rust-lang/rust/issues/{}\" title=\"Tracking issue for {}\">unstable</a>",
+        Some(ConstStability { level: StabilityLevel::Unstable { issue, .. }, feature, .. }) => {
+            let unstable = if let Some(n) = issue {
+                format!(
+                    r#"<a href="https://github.com/rust-lang/rust/issues/{}" title="Tracking issue for {}">unstable</a>"#,
                     n, feature
-                );
+                )
             } else {
-                write!(w, "unstable");
-            }
-            write!(w, ")</span>");
+                String::from("unstable")
+            };
+
+            Some((String::from("const unstable"), format!("const: {}", unstable)))
         }
-        // stable
-        (Some(v), _) if ver != containing_ver => {
-            write!(
-                w,
-                "<span class=\"since\" title=\"Stable since Rust version {0}\">{0}</span>",
-                v
-            );
+        _ => None,
+    };
+
+    if let Some((const_title, const_stability)) = const_title_and_stability {
+        if !title.is_empty() {
+            title.push_str(&format!(", {}", const_title));
+        } else {
+            title.push_str(&const_title);
+        }
+
+        if !stability.is_empty() {
+            stability.push_str(&format!(" ({})", const_stability));
+        } else {
+            stability.push_str(&const_stability);
         }
-        _ => return false,
     }
-    true
+
+    if !stability.is_empty() {
+        write!(w, r#"<span class="since" title="{}">{}</span>"#, title, stability);
+    }
+
+    !stability.is_empty()
 }
 
 fn render_assoc_item(
diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
index 44a9a571fa1..d0244351b59 100644
--- a/src/librustdoc/html/static/css/rustdoc.css
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -148,11 +148,11 @@ h1.fqn {
 }
 .main-heading {
 	display: flex;
+	flex-wrap: wrap;
+	justify-content: space-between;
+	border-bottom: 1px dashed #DDDDDD;
+	padding-bottom: 6px;
 	margin-bottom: 15px;
-
-	/* workaround to keep flex from breaking below 700 px width due to the float: right on the nav
-	   above the h1 */
-	padding-left: 1px;
 }
 .main-heading a:hover {
 	text-decoration: underline;
@@ -623,11 +623,7 @@ nav.sub {
 
 .content .out-of-band {
 	flex-grow: 0;
-	text-align: right;
-	margin-left: auto;
-	margin-right: 0;
 	font-size: 1.15rem;
-	padding: 0 0 0 12px;
 	font-weight: normal;
 	float: right;
 }
@@ -1748,10 +1744,25 @@ details.rustdoc-toggle[open] > summary.hideme::after {
 		padding-top: 0px;
 	}
 
-	.rustdoc {
+	.rustdoc,
+	.main-heading {
 		flex-direction: column;
 	}
 
+	.content .out-of-band {
+		text-align: left;
+		margin-left: initial;
+		padding: initial;
+	}
+
+	.content .out-of-band .since::before {
+		content: "Since ";
+	}
+
+	#copy-path {
+		display: none;
+	}
+
 	/* Hide the logo and item name from the sidebar. Those are displayed
 	   in the mobile-topbar instead. */
 	.sidebar .sidebar-logo,