Auto merge of #154455 - jhpratt:rollup-I3JcUWU, r=jhpratt

Rollup of 6 pull requests

Successful merges:

 - #152457 (Pass -pg to linker when using -Zinstrument-mcount)
 - #154031 (Remove divergence check from check_expr_array)
 - #154418 (move many tests out of `ui/unsafe`)
 - #154441 (bootstrap: force a CI LLVM stamp bump)
 - #153675 (simd_add/sub/mul/neg: document overflow behavior)
 - #154430 (Create GPU target notification group)

Author: bors

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -2767,6 +2767,10 @@ fn add_order_independent_options(
         cmd.pgo_gen();
     }
 
+    if sess.opts.unstable_opts.instrument_mcount {
+        cmd.enable_profiling();
+    }
+
     if sess.opts.cg.control_flow_guard != CFGuard::Disabled {
         cmd.control_flow_guard();
     }

compiler/rustc_codegen_ssa/src/back/linker.rs

@@ -352,6 +352,7 @@ pub(crate) trait Linker {
     fn add_no_exec(&mut self) {}
     fn add_as_needed(&mut self) {}
     fn reset_per_library_state(&mut self) {}
+    fn enable_profiling(&mut self) {}
 }
 
 impl dyn Linker + '_ {
@@ -732,6 +733,19 @@ impl<'a> Linker for GccLinker<'a> {
         self.link_or_cc_args(&["-u", "__llvm_profile_runtime"]);
     }
 
+    fn enable_profiling(&mut self) {
+        // This flag is also used when linking to choose target specific
+        // libraries needed to enable profiling.
+        self.cc_arg("-pg");
+        // On windows-gnu targets, libgmon also needs to be linked, and this
+        // requires readding libraries to satisfy its dependencies.
+        if self.sess.target.is_like_windows {
+            self.cc_arg("-lgmon");
+            self.cc_arg("-lkernel32");
+            self.cc_arg("-lmsvcrt");
+        }
+    }
+
     fn control_flow_guard(&mut self) {}
 
     fn ehcont_guard(&mut self) {}

compiler/rustc_hir_typeck/src/expr.rs

@@ -1660,14 +1660,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expr: &'tcx hir::Expr<'tcx>,
     ) -> Ty<'tcx> {
         let element_ty = if !args.is_empty() {
-            // This shouldn't happen unless there's another error
-            // (e.g., never patterns in inappropriate contexts).
-            if self.diverges.get() != Diverges::Maybe {
-                self.dcx()
-                    .struct_span_err(expr.span, "unexpected divergence state in checking array")
-                    .delay_as_bug();
-            }
-
             let coerce_to = expected
                 .to_option(self)
                 .and_then(|uty| {

compiler/rustc_target/src/spec/base/windows_gnu.rs

@@ -106,6 +106,7 @@ pub(crate) fn opts() -> TargetOptions {
         // FIXME(davidtwco): Support Split DWARF on Windows GNU - may require LLVM changes to
         // output DWO, despite using DWARF, doesn't use ELF..
         supported_split_debuginfo: Cow::Borrowed(&[SplitDebuginfo::Off]),
+        mcount: "_mcount".into(),
         ..Default::default()
     }
 }

compiler/rustc_target/src/spec/base/windows_gnullvm.rs

@@ -53,6 +53,7 @@ pub(crate) fn opts() -> TargetOptions {
         // FIXME(davidtwco): Support Split DWARF on Windows GNU - may require LLVM changes to
         // output DWO, despite using DWARF, doesn't use ELF..
         supported_split_debuginfo: Cow::Borrowed(&[SplitDebuginfo::Off]),
+        mcount: "_mcount".into(),
         ..Default::default()
     }
 }

library/core/src/intrinsics/simd.rs

@@ -62,20 +62,23 @@ pub const unsafe fn simd_splat<T, U>(value: U) -> T;
 /// Adds two simd vectors elementwise.
 ///
 /// `T` must be a vector of integers or floats.
+/// For integers, wrapping arithmetic is used.
 #[rustc_intrinsic]
 #[rustc_nounwind]
 pub const unsafe fn simd_add<T>(x: T, y: T) -> T;
 
 /// Subtracts `rhs` from `lhs` elementwise.
 ///
 /// `T` must be a vector of integers or floats.
+/// For integers, wrapping arithmetic is used.
 #[rustc_intrinsic]
 #[rustc_nounwind]
 pub const unsafe fn simd_sub<T>(lhs: T, rhs: T) -> T;
 
 /// Multiplies two simd vectors elementwise.
 ///
 /// `T` must be a vector of integers or floats.
+/// For integers, wrapping arithmetic is used.
 #[rustc_intrinsic]
 #[rustc_nounwind]
 pub const unsafe fn simd_mul<T>(x: T, y: T) -> T;
@@ -233,8 +236,7 @@ pub const unsafe fn simd_as<T, U>(x: T) -> U;
 /// Negates a vector elementwise.
 ///
 /// `T` must be a vector of integers or floats.
-///
-/// Rust panics for `-<int>::Min` due to overflow, but it is not UB with this intrinsic.
+/// For integers, wrapping arithmetic is used.
 #[rustc_intrinsic]
 #[rustc_nounwind]
 pub const unsafe fn simd_neg<T>(x: T) -> T;

src/bootstrap/download-ci-llvm-stamp

@@ -1,4 +1,4 @@
 Change this file to make users of the `download-ci-llvm` configuration download
 a new version of LLVM from CI, even if the LLVM submodule hasn’t changed.
 
-Last change is for: https://github.com/rust-lang/rust/pull/153179
+Last change is for: https://github.com/rust-lang/rust/pull/151063

tests/run-make/instrument-mcount-link-pg/main.rs

@@ -0,0 +1,3 @@
+fn main() {
+    println!("Hello World!");
+}

tests/run-make/instrument-mcount-link-pg/rmake.rs

@@ -0,0 +1,19 @@
+// When building a binary instrumented with mcount, verify the
+// binary is linked with the correct crt to enable profiling.
+//
+//@ only-gnu
+//@ ignore-cross-compile
+
+use run_make_support::{path, run, rustc};
+
+fn main() {
+    // Compile instrumentation enabled binary, and verify -pg is passed
+    let link_args =
+        rustc().input("main.rs").arg("-Zinstrument-mcount").print("link-args").run().stdout_utf8();
+    assert!(link_args.contains("\"-pg\""));
+
+    // Run it, and verify gmon.out is created
+    assert!(!path("gmon.out").exists());
+    run("main");
+    assert!(path("gmon.out").exists());
+}

tests/ui/reachable/never-pattern-closure-param-array.rs

@@ -0,0 +1,13 @@
+//@ check-pass
+//@ edition: 2024
+
+#![feature(never_patterns)]
+#![allow(incomplete_features)]
+#![allow(unreachable_code)]
+
+fn main() {
+    let _ = Some({
+        return;
+    })
+    .map(|!| [1]);
+}