Auto merge of #78270 - JohnTitor:rollup-bldrjh5, r=JohnTitor

Rollup of 17 pull requests

Successful merges:

 - #77268 (Link to "Contributing to Rust" rather than "Getting Started".)
 - #77339 (Implement TryFrom between NonZero types.)
 - #77488 (Mark `repr128` as `incomplete_features`)
 - #77890 (Fixing escaping to ensure generation of welformed json.)
 - #77918 (Cleanup network tests)
 - #77920 (Avoid extraneous space between visibility kw and ident for statics)
 - #77969 (Doc formating consistency between slice sort and sort_unstable, and big O notation consistency)
 - #78098 (Clean up and improve some docs)
 - #78116 (Make inline const work in range patterns)
 - #78153 (Sync LLVM submodule if it has been initialized)
 - #78163 (Clean up lib docs)
 - #78169 (Update cargo)
 - #78231 (Make closures inherit the parent function's target features)
 - #78235 (Explain where the closure return type was inferred)
 - #78255 (Reduce diagram mess in 'match arms have incompatible types' error)
 - #78263 (Add regression test of issue-77668)
 - #78265 (Add some inference-related regression tests about incorrect diagnostics)

Failed merges:

r? `@ghost`

3 files changed, 21 insertions, 12 deletions

diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs
index 698a7e7d9cd..78c95428c72 100644
--- a/compiler/rustc_parse/src/parser/expr.rs
+++ b/compiler/rustc_parse/src/parser/expr.rs
@@ -1062,8 +1062,8 @@ impl<'a> Parser<'a> {
             })
         } else if self.eat_keyword(kw::Unsafe) {
             self.parse_block_expr(None, lo, BlockCheckMode::Unsafe(ast::UserProvided), attrs)
-        } else if self.check_inline_const() {
-            self.parse_const_expr(lo.to(self.token.span))
+        } else if self.check_inline_const(0) {
+            self.parse_const_block(lo.to(self.token.span))
         } else if self.is_do_catch_block() {
             self.recover_do_catch(attrs)
         } else if self.is_try_block() {
diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs
index fb825256d92..8ff97453c14 100644
--- a/compiler/rustc_parse/src/parser/mod.rs
+++ b/compiler/rustc_parse/src/parser/mod.rs
@@ -522,9 +522,9 @@ impl<'a> Parser<'a> {
         self.check_or_expected(self.token.can_begin_const_arg(), TokenType::Const)
     }
 
-    fn check_inline_const(&mut self) -> bool {
-        self.check_keyword(kw::Const)
-            && self.look_ahead(1, |t| match t.kind {
+    fn check_inline_const(&self, dist: usize) -> bool {
+        self.is_keyword_ahead(dist, &[kw::Const])
+            && self.look_ahead(dist + 1, |t| match t.kind {
                 token::Interpolated(ref nt) => matches!(**nt, token::NtBlock(..)),
                 token::OpenDelim(DelimToken::Brace) => true,
                 _ => false,
@@ -864,7 +864,7 @@ impl<'a> Parser<'a> {
     }
 
     /// Parses inline const expressions.
-    fn parse_const_expr(&mut self, span: Span) -> PResult<'a, P<Expr>> {
+    fn parse_const_block(&mut self, span: Span) -> PResult<'a, P<Expr>> {
         self.sess.gated_spans.gate(sym::inline_const, span);
         self.eat_keyword(kw::Const);
         let blk = self.parse_block()?;
diff --git a/compiler/rustc_parse/src/parser/pat.rs b/compiler/rustc_parse/src/parser/pat.rs
index 15db2066a30..27fe75a23b6 100644
--- a/compiler/rustc_parse/src/parser/pat.rs
+++ b/compiler/rustc_parse/src/parser/pat.rs
@@ -313,9 +313,15 @@ impl<'a> Parser<'a> {
             let pat = self.parse_pat_with_range_pat(false, None)?;
             self.sess.gated_spans.gate(sym::box_patterns, lo.to(self.prev_token.span));
             PatKind::Box(pat)
-        } else if self.check_inline_const() {
+        } else if self.check_inline_const(0) {
             // Parse `const pat`
-            PatKind::Lit(self.parse_const_expr(lo.to(self.token.span))?)
+            let const_expr = self.parse_const_block(lo.to(self.token.span))?;
+
+            if let Some(re) = self.parse_range_end() {
+                self.parse_pat_range_begin_with(const_expr, re)?
+            } else {
+                PatKind::Lit(const_expr)
+            }
         } else if self.can_be_ident_pat() {
             // Parse `ident @ pat`
             // This can give false positives and parse nullary enums,
@@ -717,16 +723,19 @@ impl<'a> Parser<'a> {
 
     /// Is the token `dist` away from the current suitable as the start of a range patterns end?
     fn is_pat_range_end_start(&self, dist: usize) -> bool {
-        self.look_ahead(dist, |t| {
-            t.is_path_start() // e.g. `MY_CONST`;
+        self.check_inline_const(dist)
+            || self.look_ahead(dist, |t| {
+                t.is_path_start() // e.g. `MY_CONST`;
                 || t.kind == token::Dot // e.g. `.5` for recovery;
                 || t.can_begin_literal_maybe_minus() // e.g. `42`.
                 || t.is_whole_expr()
-        })
+            })
     }
 
     fn parse_pat_range_end(&mut self) -> PResult<'a, P<Expr>> {
-        if self.check_path() {
+        if self.check_inline_const(0) {
+            self.parse_const_block(self.token.span)
+        } else if self.check_path() {
             let lo = self.token.span;
             let (qself, path) = if self.eat_lt() {
                 // Parse a qualified path