Auto merge of #143338 - matthiaskrgr:rollup-ykaxh04, r=matthiaskrgr

Rollup of 11 pull requests

Successful merges:

 - rust-lang/rust#131923 (Derive `Copy` and `Hash` for `IntErrorKind`)
 - rust-lang/rust#138340 (Remove some unsized tuple impls now that we don't support unsizing tuples anymore)
 - rust-lang/rust#141219 (Change `{Box,Arc,Rc,Weak}::into_raw` to only work with `A = Global`)
 - rust-lang/rust#142212 (bootstrap: validate `rust.codegen-backends` & `target.<triple>.codegen-backends`)
 - rust-lang/rust#142237 (Detect more cases of unused_parens around types)
 - rust-lang/rust#142964 (Attribute rework: a parser for single attributes without arguments)
 - rust-lang/rust#143070 (Rewrite `macro_rules!` parser to not use the MBE engine itself)
 - rust-lang/rust#143235 (Assemble const bounds via normal item bounds in old solver too)
 - rust-lang/rust#143261 (Feed `explicit_predicates_of` instead of `predicates_of`)
 - rust-lang/rust#143276 (loop match: handle opaque patterns)
 - rust-lang/rust#143306 (Add `track_caller` attributes to trace origin of Clippy lints)

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

try-job: aarch64-apple
try-job: x86_64-msvc-1
try-job: x86_64-gnu
try-job: dist-i586-gnu-i586-i686-musl
try-job: test-various

5 files changed, 87 insertions, 36 deletions

diff --git a/src/bootstrap/src/core/config/toml/rust.rs b/src/bootstrap/src/core/config/toml/rust.rs
index 642f2f2271d..ac5eaea3bcb 100644
--- a/src/bootstrap/src/core/config/toml/rust.rs
+++ b/src/bootstrap/src/core/config/toml/rust.rs
@@ -393,6 +393,27 @@ pub fn check_incompatible_options_for_ci_rustc(
     Ok(())
 }
 
+pub(crate) const VALID_CODEGEN_BACKENDS: &[&str] = &["llvm", "cranelift", "gcc"];
+
+pub(crate) fn validate_codegen_backends(backends: Vec<String>, section: &str) -> Vec<String> {
+    for backend in &backends {
+        if let Some(stripped) = backend.strip_prefix(CODEGEN_BACKEND_PREFIX) {
+            panic!(
+                "Invalid value '{backend}' for '{section}.codegen-backends'. \
+                Codegen backends are defined without the '{CODEGEN_BACKEND_PREFIX}' prefix. \
+                Please, use '{stripped}' instead."
+            )
+        }
+        if !VALID_CODEGEN_BACKENDS.contains(&backend.as_str()) {
+            println!(
+                "HELP: '{backend}' for '{section}.codegen-backends' might fail. \
+                List of known good values: {VALID_CODEGEN_BACKENDS:?}"
+            );
+        }
+    }
+    backends
+}
+
 impl Config {
     pub fn apply_rust_config(
         &mut self,
@@ -571,24 +592,10 @@ impl Config {
             set(&mut self.ehcont_guard, ehcont_guard);
             self.llvm_libunwind_default =
                 llvm_libunwind.map(|v| v.parse().expect("failed to parse rust.llvm-libunwind"));
-
-            if let Some(ref backends) = codegen_backends {
-                let available_backends = ["llvm", "cranelift", "gcc"];
-
-                self.rust_codegen_backends = backends.iter().map(|s| {
-                    if let Some(backend) = s.strip_prefix(CODEGEN_BACKEND_PREFIX) {
-                        if available_backends.contains(&backend) {
-                            panic!("Invalid value '{s}' for 'rust.codegen-backends'. Instead, please use '{backend}'.");
-                        } else {
-                            println!("HELP: '{s}' for 'rust.codegen-backends' might fail. \
-                                Codegen backends are mostly defined without the '{CODEGEN_BACKEND_PREFIX}' prefix. \
-                                In this case, it would be referred to as '{backend}'.");
-                        }
-                    }
-
-                    s.clone()
-                }).collect();
-            }
+            set(
+                &mut self.rust_codegen_backends,
+                codegen_backends.map(|backends| validate_codegen_backends(backends, "rust")),
+            );
 
             self.rust_codegen_units = codegen_units.map(threads_from_config);
             self.rust_codegen_units_std = codegen_units_std.map(threads_from_config);
diff --git a/src/bootstrap/src/core/config/toml/target.rs b/src/bootstrap/src/core/config/toml/target.rs
index b9f6780ca3f..337276948b3 100644
--- a/src/bootstrap/src/core/config/toml/target.rs
+++ b/src/bootstrap/src/core/config/toml/target.rs
@@ -16,7 +16,7 @@ use std::collections::HashMap;
 
 use serde::{Deserialize, Deserializer};
 
-use crate::core::build_steps::compile::CODEGEN_BACKEND_PREFIX;
+use crate::core::config::toml::rust::validate_codegen_backends;
 use crate::core::config::{LlvmLibunwind, Merge, ReplaceOpt, SplitDebuginfo, StringOrBool};
 use crate::{Config, HashSet, PathBuf, TargetSelection, define_config, exit};
 
@@ -142,23 +142,9 @@ impl Config {
                 target.rpath = cfg.rpath;
                 target.optimized_compiler_builtins = cfg.optimized_compiler_builtins;
                 target.jemalloc = cfg.jemalloc;
-
-                if let Some(ref backends) = cfg.codegen_backends {
-                    let available_backends = ["llvm", "cranelift", "gcc"];
-
-                    target.codegen_backends = Some(backends.iter().map(|s| {
-                        if let Some(backend) = s.strip_prefix(CODEGEN_BACKEND_PREFIX) {
-                            if available_backends.contains(&backend) {
-                                panic!("Invalid value '{s}' for 'target.{triple}.codegen-backends'. Instead, please use '{backend}'.");
-                            } else {
-                                println!("HELP: '{s}' for 'target.{triple}.codegen-backends' might fail. \
-                                    Codegen backends are mostly defined without the '{CODEGEN_BACKEND_PREFIX}' prefix. \
-                                    In this case, it would be referred to as '{backend}'.");
-                            }
-                        }
-
-                        s.clone()
-                    }).collect());
+                if let Some(backends) = cfg.codegen_backends {
+                    target.codegen_backends =
+                        Some(validate_codegen_backends(backends, &format!("target.{triple}")))
                 }
 
                 target.split_debuginfo = cfg.split_debuginfo.as_ref().map(|v| {
diff --git a/src/tools/clippy/clippy_utils/src/diagnostics.rs b/src/tools/clippy/clippy_utils/src/diagnostics.rs
index dc240dd067b..8453165818b 100644
--- a/src/tools/clippy/clippy_utils/src/diagnostics.rs
+++ b/src/tools/clippy/clippy_utils/src/diagnostics.rs
@@ -98,6 +98,7 @@ fn validate_diag(diag: &Diag<'_, impl EmissionGuarantee>) {
 /// 17 |     std::mem::forget(seven);
 ///    |     ^^^^^^^^^^^^^^^^^^^^^^^
 /// ```
+#[track_caller]
 pub fn span_lint<T: LintContext>(cx: &T, lint: &'static Lint, sp: impl Into<MultiSpan>, msg: impl Into<DiagMessage>) {
     #[expect(clippy::disallowed_methods)]
     cx.span_lint(lint, sp, |diag| {
@@ -143,6 +144,7 @@ pub fn span_lint<T: LintContext>(cx: &T, lint: &'static Lint, sp: impl Into<Mult
 ///    |
 ///    = help: consider using `f64::NAN` if you would like a constant representing NaN
 /// ```
+#[track_caller]
 pub fn span_lint_and_help<T: LintContext>(
     cx: &T,
     lint: &'static Lint,
@@ -203,6 +205,7 @@ pub fn span_lint_and_help<T: LintContext>(
 /// 10 |     forget(&SomeStruct);
 ///    |            ^^^^^^^^^^^
 /// ```
+#[track_caller]
 pub fn span_lint_and_note<T: LintContext>(
     cx: &T,
     lint: &'static Lint,
@@ -244,6 +247,7 @@ pub fn span_lint_and_note<T: LintContext>(
 /// If you're unsure which function you should use, you can test if the `#[expect]` attribute works
 /// where you would expect it to.
 /// If it doesn't, you likely need to use [`span_lint_hir_and_then`] instead.
+#[track_caller]
 pub fn span_lint_and_then<C, S, M, F>(cx: &C, lint: &'static Lint, sp: S, msg: M, f: F)
 where
     C: LintContext,
@@ -286,6 +290,7 @@ where
 /// Instead, use this function and also pass the `HirId` of `<expr_1>`, which will let
 /// the compiler check lint level attributes at the place of the expression and
 /// the `#[allow]` will work.
+#[track_caller]
 pub fn span_lint_hir(cx: &LateContext<'_>, lint: &'static Lint, hir_id: HirId, sp: Span, msg: impl Into<DiagMessage>) {
     #[expect(clippy::disallowed_methods)]
     cx.tcx.node_span_lint(lint, hir_id, sp, |diag| {
@@ -321,6 +326,7 @@ pub fn span_lint_hir(cx: &LateContext<'_>, lint: &'static Lint, hir_id: HirId, s
 /// Instead, use this function and also pass the `HirId` of `<expr_1>`, which will let
 /// the compiler check lint level attributes at the place of the expression and
 /// the `#[allow]` will work.
+#[track_caller]
 pub fn span_lint_hir_and_then(
     cx: &LateContext<'_>,
     lint: &'static Lint,
@@ -374,6 +380,7 @@ pub fn span_lint_hir_and_then(
 ///     = note: `-D fold-any` implied by `-D warnings`
 /// ```
 #[cfg_attr(not(debug_assertions), expect(clippy::collapsible_span_lint_calls))]
+#[track_caller]
 pub fn span_lint_and_sugg<T: LintContext>(
     cx: &T,
     lint: &'static Lint,
diff --git a/src/tools/clippy/tests/ui/track-diagnostics-clippy.rs b/src/tools/clippy/tests/ui/track-diagnostics-clippy.rs
new file mode 100644
index 00000000000..2e67fb65efc
--- /dev/null
+++ b/src/tools/clippy/tests/ui/track-diagnostics-clippy.rs
@@ -0,0 +1,22 @@
+//@compile-flags: -Z track-diagnostics
+//@no-rustfix
+
+// Normalize the emitted location so this doesn't need
+// updating everytime someone adds or removes a line.
+//@normalize-stderr-test: ".rs:\d+:\d+" -> ".rs:LL:CC"
+
+#![warn(clippy::let_and_return, clippy::unnecessary_cast)]
+
+fn main() {
+    // Check the provenance of a lint sent through `LintContext::span_lint()`
+    let a = 3u32;
+    let b = a as u32;
+    //~^ unnecessary_cast
+    
+    // Check the provenance of a lint sent through `TyCtxt::node_span_lint()`
+    let c = {
+        let d = 42;
+        d
+        //~^ let_and_return
+    };
+}
diff --git a/src/tools/clippy/tests/ui/track-diagnostics-clippy.stderr b/src/tools/clippy/tests/ui/track-diagnostics-clippy.stderr
new file mode 100644
index 00000000000..f3aca685417
--- /dev/null
+++ b/src/tools/clippy/tests/ui/track-diagnostics-clippy.stderr
@@ -0,0 +1,29 @@
+error: casting to the same type is unnecessary (`u32` -> `u32`)
+  --> tests/ui/track-diagnostics-clippy.rs:LL:CC
+   |
+LL |     let b = a as u32;
+   |             ^^^^^^^^ help: try: `a`
+-Ztrack-diagnostics: created at src/tools/clippy/clippy_lints/src/casts/unnecessary_cast.rs:LL:CC
+   |
+   = note: `-D clippy::unnecessary-cast` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::unnecessary_cast)]`
+
+error: returning the result of a `let` binding from a block
+  --> tests/ui/track-diagnostics-clippy.rs:LL:CC
+   |
+LL |         let d = 42;
+   |         ----------- unnecessary `let` binding
+LL |         d
+   |         ^
+-Ztrack-diagnostics: created at src/tools/clippy/clippy_lints/src/returns.rs:LL:CC
+   |
+   = note: `-D clippy::let-and-return` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::let_and_return)]`
+help: return the expression directly
+   |
+LL ~         
+LL ~         42
+   |
+
+error: aborting due to 2 previous errors
+