diff --git a/.editorconfig b/.editorconfig
index ec6e107d547..03aab32bfc6 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -11,6 +11,7 @@ trim_trailing_whitespace = true
 insert_final_newline = true
 indent_style = space
 indent_size = 4
+max_line_length = 100
 
 [*.md]
 # double whitespace at end of line
diff --git a/compiler/rustc_hir_typeck/src/expr.rs b/compiler/rustc_hir_typeck/src/expr.rs
index c17aae22ba5..68e096e3bd0 100644
--- a/compiler/rustc_hir_typeck/src/expr.rs
+++ b/compiler/rustc_hir_typeck/src/expr.rs
@@ -2810,23 +2810,26 @@ fn check_expr_index(
                         "cannot index into a value of type `{base_t}`",
                     );
                     // Try to give some advice about indexing tuples.
-                    if let ty::Tuple(..) = base_t.kind() {
+                    if let ty::Tuple(types) = base_t.kind() {
                         let mut needs_note = true;
                         // If the index is an integer, we can show the actual
                         // fixed expression:
-                        if let ExprKind::Lit(ref lit) = idx.kind {
-                            if let ast::LitKind::Int(i, ast::LitIntType::Unsuffixed) = lit.node {
-                                let snip = self.tcx.sess.source_map().span_to_snippet(base.span);
-                                if let Ok(snip) = snip {
-                                    err.span_suggestion(
-                                        expr.span,
-                                        "to access tuple elements, use",
-                                        format!("{snip}.{i}"),
-                                        Applicability::MachineApplicable,
-                                    );
-                                    needs_note = false;
-                                }
+                        if let ExprKind::Lit(ref lit) = idx.kind
+                            && let ast::LitKind::Int(i, ast::LitIntType::Unsuffixed) = lit.node
+                            && i < types.len().try_into().expect("expected tuple index to be < usize length")
+                        {
+                            let snip = self.tcx.sess.source_map().span_to_snippet(base.span);
+                            if let Ok(snip) = snip {
+                                err.span_suggestion(
+                                    expr.span,
+                                    "to access tuple elements, use",
+                                    format!("{snip}.{i}"),
+                                    Applicability::MachineApplicable,
+                                );
+                                needs_note = false;
                             }
+                        } else if let ExprKind::Path(..) = idx.peel_borrows().kind {
+                            err.span_label(idx.span, "cannot access tuple elements at a variable index");
                         }
                         if needs_note {
                             err.help(
diff --git a/config.example.toml b/config.example.toml
index 15c6bc0f123..b27a34e61c5 100644
--- a/config.example.toml
+++ b/config.example.toml
@@ -585,7 +585,7 @@ changelog-seen = 2
 # Having the git information can cause a lot of rebuilds during development.
 #
 # FIXME(#76720): this can causes bugs if different compilers reuse the same metadata cache.
-#ignore-git = if rust.channel == "dev" { true } else { false }
+#omit-git-hash = if rust.channel == "dev" { true } else { false }
 
 # Whether to create a source tarball by default when running `x dist`.
 #
diff --git a/library/core/src/primitive_docs.rs b/library/core/src/primitive_docs.rs
index bf8339335dd..51e6947a9c2 100644
--- a/library/core/src/primitive_docs.rs
+++ b/library/core/src/primitive_docs.rs
@@ -1362,6 +1362,7 @@ mod prim_usize {}
 /// * [`Hash`]
 /// * [`ToSocketAddrs`]
 /// * [`Send`] \(`&T` references also require <code>T: [Sync]</code>)
+/// * [`Sync`]
 ///
 /// [`std::fmt`]: fmt
 /// [`Hash`]: hash::Hash
diff --git a/library/std/src/primitive_docs.rs b/library/std/src/primitive_docs.rs
index bf8339335dd..51e6947a9c2 100644
--- a/library/std/src/primitive_docs.rs
+++ b/library/std/src/primitive_docs.rs
@@ -1362,6 +1362,7 @@ mod prim_usize {}
 /// * [`Hash`]
 /// * [`ToSocketAddrs`]
 /// * [`Send`] \(`&T` references also require <code>T: [Sync]</code>)
+/// * [`Sync`]
 ///
 /// [`std::fmt`]: fmt
 /// [`Hash`]: hash::Hash
diff --git a/src/bootstrap/channel.rs b/src/bootstrap/channel.rs
index eae81b9fc69..390047f6fdc 100644
--- a/src/bootstrap/channel.rs
+++ b/src/bootstrap/channel.rs
@@ -19,7 +19,7 @@ pub enum GitInfo {
     #[default]
     Absent,
     /// This is a git repository.
-    /// If the info should be used (`ignore_git` is false), this will be
+    /// If the info should be used (`omit_git_hash` is false), this will be
     /// `Some`, otherwise it will be `None`.
     Present(Option<Info>),
     /// This is not a git repostory, but the info can be fetched from the
@@ -35,7 +35,7 @@ pub struct Info {
 }
 
 impl GitInfo {
-    pub fn new(ignore_git: bool, dir: &Path) -> GitInfo {
+    pub fn new(omit_git_hash: bool, dir: &Path) -> GitInfo {
         // See if this even begins to look like a git dir
         if !dir.join(".git").exists() {
             match read_commit_info_file(dir) {
@@ -52,7 +52,7 @@ pub fn new(ignore_git: bool, dir: &Path) -> GitInfo {
 
         // If we're ignoring the git info, we don't actually need to collect it, just make sure this
         // was a git repo in the first place.
-        if ignore_git {
+        if omit_git_hash {
             return GitInfo::Present(None);
         }
 
diff --git a/src/bootstrap/config.rs b/src/bootstrap/config.rs
index f038aceb34c..dd65dc91c0c 100644
--- a/src/bootstrap/config.rs
+++ b/src/bootstrap/config.rs
@@ -77,7 +77,7 @@ pub struct Config {
     pub tools: Option<HashSet<String>>,
     pub sanitizers: bool,
     pub profiler: bool,
-    pub ignore_git: bool,
+    pub omit_git_hash: bool,
     pub exclude: Vec<TaskPath>,
     pub include_default_paths: bool,
     pub rustc_error_format: Option<String>,
@@ -764,7 +764,7 @@ struct Rust {
         verbose_tests: Option<bool> = "verbose-tests",
         optimize_tests: Option<bool> = "optimize-tests",
         codegen_tests: Option<bool> = "codegen-tests",
-        ignore_git: Option<bool> = "ignore-git",
+        omit_git_hash: Option<bool> = "omit-git-hash",
         dist_src: Option<bool> = "dist-src",
         save_toolstates: Option<String> = "save-toolstates",
         codegen_backends: Option<Vec<String>> = "codegen-backends",
@@ -1097,7 +1097,7 @@ fn parse_inner<'a>(args: &[String], get_toml: impl 'a + Fn(&Path) -> TomlConfig)
         let mut debuginfo_level_tools = None;
         let mut debuginfo_level_tests = None;
         let mut optimize = None;
-        let mut ignore_git = None;
+        let mut omit_git_hash = None;
 
         if let Some(rust) = toml.rust {
             debug = rust.debug;
@@ -1118,7 +1118,7 @@ fn parse_inner<'a>(args: &[String], get_toml: impl 'a + Fn(&Path) -> TomlConfig)
                 .map(|v| v.expect("invalid value for rust.split_debuginfo"))
                 .unwrap_or(SplitDebuginfo::default_for_platform(&config.build.triple));
             optimize = rust.optimize;
-            ignore_git = rust.ignore_git;
+            omit_git_hash = rust.omit_git_hash;
             config.rust_new_symbol_mangling = rust.new_symbol_mangling;
             set(&mut config.rust_optimize_tests, rust.optimize_tests);
             set(&mut config.codegen_tests, rust.codegen_tests);
@@ -1175,8 +1175,8 @@ fn parse_inner<'a>(args: &[String], get_toml: impl 'a + Fn(&Path) -> TomlConfig)
 
         // rust_info must be set before is_ci_llvm_available() is called.
         let default = config.channel == "dev";
-        config.ignore_git = ignore_git.unwrap_or(default);
-        config.rust_info = GitInfo::new(config.ignore_git, &config.src);
+        config.omit_git_hash = omit_git_hash.unwrap_or(default);
+        config.rust_info = GitInfo::new(config.omit_git_hash, &config.src);
 
         if let Some(llvm) = toml.llvm {
             match llvm.ccache {
diff --git a/src/bootstrap/defaults/config.codegen.toml b/src/bootstrap/defaults/config.codegen.toml
index 20b2699c761..113df88d7c3 100644
--- a/src/bootstrap/defaults/config.codegen.toml
+++ b/src/bootstrap/defaults/config.codegen.toml
@@ -9,6 +9,8 @@ compiler-docs = true
 assertions = true
 # enable warnings during the llvm compilation
 enable-warnings = true
+# build llvm from source
+download-ci-llvm = false
 
 [rust]
 # This enables `RUSTC_LOG=debug`, avoiding confusing situations
diff --git a/src/bootstrap/lib.rs b/src/bootstrap/lib.rs
index e3f3ab5243e..5ee18cf6411 100644
--- a/src/bootstrap/lib.rs
+++ b/src/bootstrap/lib.rs
@@ -358,14 +358,14 @@ pub fn new(mut config: Config) -> Build {
         #[cfg(not(unix))]
         let is_sudo = false;
 
-        let ignore_git = config.ignore_git;
-        let rust_info = channel::GitInfo::new(ignore_git, &src);
-        let cargo_info = channel::GitInfo::new(ignore_git, &src.join("src/tools/cargo"));
+        let omit_git_hash = config.omit_git_hash;
+        let rust_info = channel::GitInfo::new(omit_git_hash, &src);
+        let cargo_info = channel::GitInfo::new(omit_git_hash, &src.join("src/tools/cargo"));
         let rust_analyzer_info =
-            channel::GitInfo::new(ignore_git, &src.join("src/tools/rust-analyzer"));
-        let clippy_info = channel::GitInfo::new(ignore_git, &src.join("src/tools/clippy"));
-        let miri_info = channel::GitInfo::new(ignore_git, &src.join("src/tools/miri"));
-        let rustfmt_info = channel::GitInfo::new(ignore_git, &src.join("src/tools/rustfmt"));
+            channel::GitInfo::new(omit_git_hash, &src.join("src/tools/rust-analyzer"));
+        let clippy_info = channel::GitInfo::new(omit_git_hash, &src.join("src/tools/clippy"));
+        let miri_info = channel::GitInfo::new(omit_git_hash, &src.join("src/tools/miri"));
+        let rustfmt_info = channel::GitInfo::new(omit_git_hash, &src.join("src/tools/rustfmt"));
 
         // we always try to use git for LLVM builds
         let in_tree_llvm_info = channel::GitInfo::new(false, &src.join("src/llvm-project"));
@@ -1233,7 +1233,7 @@ fn release(&self, num: &str) -> String {
         match &self.config.channel[..] {
             "stable" => num.to_string(),
             "beta" => {
-                if self.rust_info().is_managed_git_subrepository() && !self.config.ignore_git {
+                if self.rust_info().is_managed_git_subrepository() && !self.config.omit_git_hash {
                     format!("{}-beta.{}", num, self.beta_prerelease_version())
                 } else {
                     format!("{}-beta", num)
diff --git a/src/bootstrap/tool.rs b/src/bootstrap/tool.rs
index 3c9a154da9a..6a687a7903e 100644
--- a/src/bootstrap/tool.rs
+++ b/src/bootstrap/tool.rs
@@ -320,7 +320,7 @@ pub fn prepare_tool_cargo(
     cargo.env("CFG_RELEASE_NUM", &builder.version);
     cargo.env("DOC_RUST_LANG_ORG_CHANNEL", builder.doc_rust_lang_org_channel());
 
-    let info = GitInfo::new(builder.config.ignore_git, &dir);
+    let info = GitInfo::new(builder.config.omit_git_hash, &dir);
     if let Some(sha) = info.sha() {
         cargo.env("CFG_COMMIT_HASH", sha);
     }
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-distcheck/Dockerfile b/src/ci/docker/host-x86_64/x86_64-gnu-distcheck/Dockerfile
index 7e640c49f01..2217e6ee704 100644
--- a/src/ci/docker/host-x86_64/x86_64-gnu-distcheck/Dockerfile
+++ b/src/ci/docker/host-x86_64/x86_64-gnu-distcheck/Dockerfile
@@ -24,6 +24,6 @@ RUN sh /scripts/sccache.sh
 # We are disabling CI LLVM since distcheck is an offline build.
 ENV NO_DOWNLOAD_CI_LLVM 1
 
-ENV RUST_CONFIGURE_ARGS --build=x86_64-unknown-linux-gnu --set rust.ignore-git=false
+ENV RUST_CONFIGURE_ARGS --build=x86_64-unknown-linux-gnu --set rust.omit-git-hash=false
 ENV SCRIPT python3 ../x.py --stage 2 test distcheck
 ENV DIST_SRC 1
diff --git a/src/doc/unstable-book/src/language-features/lang-items.md b/src/doc/unstable-book/src/language-features/lang-items.md
index 39238dffa10..6adb3506e64 100644
--- a/src/doc/unstable-book/src/language-features/lang-items.md
+++ b/src/doc/unstable-book/src/language-features/lang-items.md
@@ -16,18 +16,26 @@ and one for deallocation. A freestanding program that uses the `Box`
 sugar for dynamic allocations via `malloc` and `free`:
 
 ```rust,ignore (libc-is-finicky)
-#![feature(lang_items, box_syntax, start, libc, core_intrinsics, rustc_private)]
+#![feature(lang_items, start, libc, core_intrinsics, rustc_private, rustc_attrs)]
 #![no_std]
 use core::intrinsics;
 use core::panic::PanicInfo;
+use core::ptr::NonNull;
 
 extern crate libc;
 
-struct Unique<T>(*mut T);
+struct Unique<T>(NonNull<T>);
 
 #[lang = "owned_box"]
 pub struct Box<T>(Unique<T>);
 
+impl<T> Box<T> {
+    pub fn new(x: T) -> Self {
+        #[rustc_box]
+        Box::new(x)
+    }
+}
+
 #[lang = "exchange_malloc"]
 unsafe fn allocate(size: usize, _align: usize) -> *mut u8 {
     let p = libc::malloc(size as libc::size_t) as *mut u8;
@@ -47,13 +55,13 @@ unsafe fn box_free<T: ?Sized>(ptr: *mut T) {
 
 #[start]
 fn main(_argc: isize, _argv: *const *const u8) -> isize {
-    let _x = box 1;
+    let _x = Box::new(1);
 
     0
 }
 
 #[lang = "eh_personality"] extern fn rust_eh_personality() {}
-#[lang = "panic_impl"] extern fn rust_begin_panic(info: &PanicInfo) -> ! { unsafe { intrinsics::abort() } }
+#[lang = "panic_impl"] extern fn rust_begin_panic(_info: &PanicInfo) -> ! { intrinsics::abort() }
 #[no_mangle] pub extern fn rust_eh_register_frames () {}
 #[no_mangle] pub extern fn rust_eh_unregister_frames () {}
 ```
diff --git a/src/doc/unstable-book/src/language-features/plugin.md b/src/doc/unstable-book/src/language-features/plugin.md
index dfbb468d4df..1fade6ce95b 100644
--- a/src/doc/unstable-book/src/language-features/plugin.md
+++ b/src/doc/unstable-book/src/language-features/plugin.md
@@ -37,7 +37,7 @@ additional checks for code style, safety, etc. Now let's write a plugin
 that warns about any item named `lintme`.
 
 ```rust,ignore (requires-stage-2)
-#![feature(box_syntax, rustc_private)]
+#![feature(rustc_private)]
 
 extern crate rustc_ast;
 
@@ -68,7 +68,7 @@ impl EarlyLintPass for Pass {
 #[no_mangle]
 fn __rustc_plugin_registrar(reg: &mut Registry) {
     reg.lint_store.register_lints(&[&TEST_LINT]);
-    reg.lint_store.register_early_pass(|| box Pass);
+    reg.lint_store.register_early_pass(|| Box::new(Pass));
 }
 ```
 
diff --git a/tests/ui/index_message.rs b/tests/ui/index_message.rs
index 87e0cde5919..88b848d6f85 100644
--- a/tests/ui/index_message.rs
+++ b/tests/ui/index_message.rs
@@ -1,4 +1,4 @@
 fn main() {
-    let z = ();
-    let _ = z[0]; //~ ERROR cannot index into a value of type `()`
+    let z = (10,);
+    let _ = z[0]; //~ ERROR cannot index into a value of type `({integer},)`
 }
diff --git a/tests/ui/index_message.stderr b/tests/ui/index_message.stderr
index 6c2b126734b..56d1d70809d 100644
--- a/tests/ui/index_message.stderr
+++ b/tests/ui/index_message.stderr
@@ -1,4 +1,4 @@
-error[E0608]: cannot index into a value of type `()`
+error[E0608]: cannot index into a value of type `({integer},)`
   --> $DIR/index_message.rs:3:13
    |
 LL |     let _ = z[0];
diff --git a/tests/ui/issues/issue-27842.rs b/tests/ui/issues/issue-27842.rs
index 3bcfa133070..060d3b34e09 100644
--- a/tests/ui/issues/issue-27842.rs
+++ b/tests/ui/issues/issue-27842.rs
@@ -8,4 +8,9 @@ fn main() {
     let i = 0_usize;
     let _ = tup[i];
     //~^ ERROR cannot index into a value of type
+
+    // the case where the index is out of bounds
+    let tup = (10,);
+    let _ = tup[3];
+    //~^ ERROR cannot index into a value of type
 }
diff --git a/tests/ui/issues/issue-27842.stderr b/tests/ui/issues/issue-27842.stderr
index 784666a639e..83333aa0c47 100644
--- a/tests/ui/issues/issue-27842.stderr
+++ b/tests/ui/issues/issue-27842.stderr
@@ -8,10 +8,20 @@ error[E0608]: cannot index into a value of type `({integer}, {integer}, {integer
   --> $DIR/issue-27842.rs:9:13
    |
 LL |     let _ = tup[i];
+   |             ^^^^-^
+   |                 |
+   |                 cannot access tuple elements at a variable index
+   |
+   = help: to access tuple elements, use tuple indexing syntax (e.g., `tuple.0`)
+
+error[E0608]: cannot index into a value of type `({integer},)`
+  --> $DIR/issue-27842.rs:14:13
+   |
+LL |     let _ = tup[3];
    |             ^^^^^^
    |
    = help: to access tuple elements, use tuple indexing syntax (e.g., `tuple.0`)
 
-error: aborting due to 2 previous errors
+error: aborting due to 3 previous errors
 
 For more information about this error, try `rustc --explain E0608`.