Auto merge of rust-lang#125131 - jieyouxu:rollup-oqprchr, r=jieyouxu

Rollup of 5 pull requests

Successful merges:

 - rust-lang#124746 (`rustc --explain E0582` additional example)
 - rust-lang#124975 (Use an helper to move the files)
 - rust-lang#125027 (Migrate `run-make/c-link-to-rust-staticlib` to `rmake`)
 - rust-lang#125084 (`rustc_hir_typeck`: Account for `skipped_ref_pats` in `expr_use_visitor`)
 - rust-lang#125104 (Migrate `run-make/no-cdylib-as-rdylib` to `rmake`)

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

Author: bors

compiler/rustc_error_codes/src/error_codes/E0582.md

@@ -27,6 +27,40 @@ fn bar<F, G>(t: F, u: G)
 fn main() { }
 ```
 
+This error also includes the use of associated types with lifetime parameters.
+```compile_fail,E0582
+trait Foo {
+    type Assoc<'a>;
+}
+
+struct Bar<X, F>
+where
+    X: Foo,
+    F: for<'a> Fn(X::Assoc<'a>) -> &'a i32
+{
+    x: X,
+    f: F
+}
+```
+This is as `Foo::Assoc<'a>` could be implemented by a type that does not use
+the `'a` parameter, so there is no guarentee that `X::Assoc<'a>` actually uses
+`'a`.
+
+To fix this we can pass a dummy parameter:
+```
+# trait Foo {
+#     type Assoc<'a>;
+# }
+struct Bar<X, F>
+where
+    X: Foo,
+    F: for<'a> Fn(X::Assoc<'a>, /* dummy */ &'a ()) -> &'a i32
+{
+    x: X,
+    f: F
+}
+```
+
 Note: The examples above used to be (erroneously) accepted by the
 compiler, but this was since corrected. See [issue #33685] for more
 details.

compiler/rustc_hir_typeck/src/expr_use_visitor.rs

@@ -18,12 +18,12 @@ use rustc_hir as hir;
 use rustc_hir::def::{CtorOf, Res};
 use rustc_hir::def_id::LocalDefId;
 use rustc_hir::{HirId, PatKind};
-use rustc_middle::{bug, span_bug};
 use rustc_middle::hir::place::ProjectionKind;
 use rustc_middle::mir::FakeReadCause;
 use rustc_middle::ty::{
     self, adjustment, AdtKind, Ty, TyCtxt, TypeFoldable, TypeVisitableExt as _,
 };
+use rustc_middle::{bug, span_bug};
 use rustc_span::{ErrorGuaranteed, Span};
 use rustc_target::abi::{FieldIdx, VariantIdx, FIRST_VARIANT};
 use rustc_trait_selection::infer::InferCtxtExt;
@@ -1181,6 +1181,10 @@ impl<'tcx, Cx: TypeInformationCtxt<'tcx>, D: Delegate<'tcx>> ExprUseVisitor<'tcx
                 debug!("pat_ty(pat={:?}) found adjusted ty `{:?}`", pat, first_ty);
                 return Ok(*first_ty);
             }
+        } else if let PatKind::Ref(subpat, _) = pat.kind
+            && self.cx.typeck_results().skipped_ref_pats().contains(pat.hir_id)
+        {
+            return self.pat_ty_adjusted(subpat);
         }
 
         self.pat_ty_unadjusted(pat)
@@ -1712,6 +1716,12 @@ impl<'tcx, Cx: TypeInformationCtxt<'tcx>, D: Delegate<'tcx>> ExprUseVisitor<'tcx
                 self.cat_pattern(place_with_id, subpat, op)?;
             }
 
+            PatKind::Ref(subpat, _)
+                if self.cx.typeck_results().skipped_ref_pats().contains(pat.hir_id) =>
+            {
+                self.cat_pattern(place_with_id, subpat, op)?;
+            }
+
             PatKind::Box(subpat) | PatKind::Ref(subpat, _) => {
                 // box p1, &p1, &mut p1. we can ignore the mutability of
                 // PatKind::Ref since that information is already contained

src/bootstrap/src/core/build_steps/dist.rs

@@ -26,7 +26,9 @@ use crate::core::build_steps::tool::{self, Tool};
 use crate::core::builder::{Builder, Kind, RunConfig, ShouldRun, Step};
 use crate::core::config::TargetSelection;
 use crate::utils::channel::{self, Info};
-use crate::utils::helpers::{exe, is_dylib, output, t, target_supports_cranelift_backend, timeit};
+use crate::utils::helpers::{
+    exe, is_dylib, move_file, output, t, target_supports_cranelift_backend, timeit,
+};
 use crate::utils::tarball::{GeneratedTarball, OverlayKind, Tarball};
 use crate::{Compiler, DependencyType, Mode, LLVM_TOOLS};
 
@@ -2024,7 +2026,7 @@ impl Step for Extended {
             builder.run(&mut cmd);
 
             if !builder.config.dry_run() {
-                t!(fs::rename(exe.join(&filename), distdir(builder).join(&filename)));
+                t!(move_file(exe.join(&filename), distdir(builder).join(&filename)));
             }
         }
     }

src/bootstrap/src/core/download.rs

@@ -12,7 +12,7 @@ use build_helper::ci::CiEnv;
 use build_helper::stage0_parser::VersionMetadata;
 use xz2::bufread::XzDecoder;
 
-use crate::utils::helpers::{check_run, exe, program_out_of_date};
+use crate::utils::helpers::{check_run, exe, move_file, program_out_of_date};
 use crate::{core::build_steps::llvm::detect_llvm_sha, utils::helpers::hex_encode};
 use crate::{t, Config};
 
@@ -209,7 +209,7 @@ impl Config {
             None => panic!("no protocol in {url}"),
         }
         t!(
-            std::fs::rename(&tempfile, dest_path),
+            move_file(&tempfile, dest_path),
             format!("failed to rename {tempfile:?} to {dest_path:?}")
         );
     }
@@ -313,7 +313,7 @@ impl Config {
             if src_path.is_dir() && dst_path.exists() {
                 continue;
             }
-            t!(fs::rename(src_path, dst_path));
+            t!(move_file(src_path, dst_path));
         }
         let dst_dir = dst.join(directory_prefix);
         if dst_dir.exists() {

src/bootstrap/src/utils/helpers.rs

@@ -150,6 +150,21 @@ pub fn symlink_dir(config: &Config, original: &Path, link: &Path) -> io::Result<
     }
 }
 
+/// Rename a file if from and to are in the same filesystem or
+/// copy and remove the file otherwise
+pub fn move_file<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<()> {
+    match fs::rename(&from, &to) {
+        // FIXME: Once `ErrorKind::CrossesDevices` is stabilized use
+        // if e.kind() == io::ErrorKind::CrossesDevices {
+        #[cfg(unix)]
+        Err(e) if e.raw_os_error() == Some(libc::EXDEV) => {
+            std::fs::copy(&from, &to)?;
+            std::fs::remove_file(&from)
+        }
+        r => r,
+    }
+}
+
 pub fn forcing_clang_based_tests() -> bool {
     if let Some(var) = env::var_os("RUSTBUILD_FORCE_CLANG_BASED_TESTS") {
         match &var.to_string_lossy().to_lowercase()[..] {

src/bootstrap/src/utils/tarball.rs

@@ -13,7 +13,7 @@ use std::{
 use crate::core::builder::Builder;
 use crate::core::{build_steps::dist::distdir, builder::Kind};
 use crate::utils::channel;
-use crate::utils::helpers::t;
+use crate::utils::helpers::{move_file, t};
 
 #[derive(Copy, Clone)]
 pub(crate) enum OverlayKind {
@@ -284,7 +284,7 @@ impl<'a> Tarball<'a> {
         // name, not "image". We rename the image directory just before passing
         // into rust-installer.
         let dest = self.temp_dir.join(self.package_name());
-        t!(std::fs::rename(&self.image_dir, &dest));
+        t!(move_file(&self.image_dir, &dest));
 
         self.run(|this, cmd| {
             let distdir = distdir(this.builder);

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -8,7 +8,6 @@ run-make/branch-protection-check-IBT/Makefile
 run-make/c-dynamic-dylib/Makefile
 run-make/c-dynamic-rlib/Makefile
 run-make/c-link-to-rust-dylib/Makefile
-run-make/c-link-to-rust-staticlib/Makefile
 run-make/c-static-dylib/Makefile
 run-make/c-static-rlib/Makefile
 run-make/c-unwind-abi-catch-lib-panic/Makefile
@@ -180,7 +179,6 @@ run-make/native-link-modifier-whole-archive/Makefile
 run-make/no-alloc-shim/Makefile
 run-make/no-builtins-attribute/Makefile
 run-make/no-builtins-lto/Makefile
-run-make/no-cdylib-as-rdylib/Makefile
 run-make/no-duplicate-libs/Makefile
 run-make/no-intermediate-extras/Makefile
 run-make/obey-crate-type-flag/Makefile

tests/run-make/c-link-to-rust-staticlib/Makefile

@@ -0,0 +1,19 @@
+// This test checks that C linking with Rust does not encounter any errors, with a static library.
+// See https://github.com/rust-lang/rust/issues/10434
+
+//@ ignore-cross-compile
+
+use run_make_support::{cc, extra_c_flags, run, rustc, static_lib};
+use std::fs;
+
+fn main() {
+    rustc().input("foo.rs").run();
+    cc().input("bar.c")
+        .input(static_lib("foo"))
+        .out_exe("bar")
+        .args(&extra_c_flags())
+        .run();
+    run("bar");
+    fs::remove_file(static_lib("foo"));
+    run("bar");
+}

tests/run-make/c-link-to-rust-staticlib/rmake.rs

@@ -0,0 +1,16 @@
+// This test produces an rlib and a cdylib from bar.rs.
+// Then, foo.rs attempts to link to the bar library.
+// If the test passes, that means rustc favored the rlib and ignored the cdylib.
+// If the test fails, that is because the cdylib was picked, which does not export
+// any Rust symbols.
+// See https://github.com/rust-lang/rust/pull/113695
+
+//@ ignore-cross-compile
+
+use run_make_support::{run, rustc};
+
+fn main() {
+    rustc().input("bar.rs").crate_type("rlib").crate_type("cdylib").run();
+    rustc().input("foo.rs").arg("-Cprefer-dynamic").run();
+    run("foo");
+}

tests/run-make/no-cdylib-as-rdylib/Makefile

@@ -0,0 +1,18 @@
+//@ run-pass
+//@ edition: 2024
+//@ compile-flags: -Zunstable-options
+
+#![allow(incomplete_features)]
+#![feature(ref_pat_eat_one_layer_2024)]
+
+struct Foo;
+//~^ WARN struct `Foo` is never constructed
+
+fn main() {
+    || {
+        //~^ WARN unused closure that must be used
+        if let Some(Some(&mut x)) = &mut Some(&mut Some(0)) {
+            let _: u32 = x;
+        }
+    };
+}

tests/run-make/no-cdylib-as-rdylib/rmake.rs

@@ -0,0 +1,24 @@
+warning: struct `Foo` is never constructed
+  --> $DIR/skipped-ref-pats-issue-125058.rs:8:8
+   |
+LL | struct Foo;
+   |        ^^^
+   |
+   = note: `#[warn(dead_code)]` on by default
+
+warning: unused closure that must be used
+  --> $DIR/skipped-ref-pats-issue-125058.rs:12:5
+   |
+LL | /     || {
+LL | |
+LL | |         if let Some(Some(&mut x)) = &mut Some(&mut Some(0)) {
+LL | |             let _: u32 = x;
+LL | |         }
+LL | |     };
+   | |_____^
+   |
+   = note: closures are lazy and do nothing unless called
+   = note: `#[warn(unused_must_use)]` on by default
+
+warning: 2 warnings emitted
+