Rollup of 6 pull requests

compiler/rustc_codegen_cranelift/patches/0029-stdlib-Disable-f16-and-f128-in-compiler-builtins.patch

@@ -16,8 +16,8 @@ index 7165c3e48af..968552ad435 100644
 
  [dependencies]
  core = { path = "../core", public = true }
--compiler_builtins = { version = "=0.1.147", features = ['rustc-dep-of-std'] }
-+compiler_builtins = { version = "=0.1.147", features = ['rustc-dep-of-std', 'no-f16-f128'] }
+-compiler_builtins = { version = "=0.1.148", features = ['rustc-dep-of-std'] }
++compiler_builtins = { version = "=0.1.148", features = ['rustc-dep-of-std', 'no-f16-f128'] }
 
  [dev-dependencies]
  rand = { version = "0.8.5", default-features = false, features = ["alloc"] }

compiler/rustc_hir_analysis/messages.ftl

@@ -605,6 +605,8 @@ hir_analysis_unused_generic_parameter_adt_no_phantom_data_help =
 hir_analysis_unused_generic_parameter_ty_alias_help =
     consider removing `{$param_name}` or referring to it in the body of the type alias
 
+hir_analysis_useless_impl_item = this item cannot be used as its where bounds are not satisfied for the `Self` type
+
 hir_analysis_value_of_associated_struct_already_specified =
     the value of the associated type `{$item_name}` in trait `{$def_path}` is already specified
     .label = re-bound here

compiler/rustc_hir_analysis/src/check/check.rs

@@ -992,6 +992,32 @@ fn check_impl_items_against_trait<'tcx>(
 
     let trait_def = tcx.trait_def(trait_ref.def_id);
 
+    let infcx = tcx.infer_ctxt().ignoring_regions().build(TypingMode::non_body_analysis());
+
+    let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
+    let cause = ObligationCause::misc(tcx.def_span(impl_id), impl_id);
+    let param_env = tcx.param_env(impl_id);
+
+    let self_is_guaranteed_unsized = match tcx
+        .struct_tail_raw(
+            trait_ref.self_ty(),
+            |ty| {
+                ocx.structurally_normalize_ty(&cause, param_env, ty).unwrap_or_else(|_| {
+                    Ty::new_error_with_message(
+                        tcx,
+                        tcx.def_span(impl_id),
+                        "struct tail should be computable",
+                    )
+                })
+            },
+            || (),
+        )
+        .kind()
+    {
+        ty::Dynamic(_, _, ty::DynKind::Dyn) | ty::Slice(_) | ty::Str => true,
+        _ => false,
+    };
+
     for &impl_item in impl_item_refs {
         let ty_impl_item = tcx.associated_item(impl_item);
         let ty_trait_item = if let Some(trait_item_id) = ty_impl_item.trait_item_def_id {
@@ -1021,6 +1047,15 @@ fn check_impl_items_against_trait<'tcx>(
             }
         }
 
+        if self_is_guaranteed_unsized && tcx.generics_require_sized_self(ty_trait_item.def_id) {
+            tcx.emit_node_span_lint(
+                rustc_lint_defs::builtin::DEAD_CODE,
+                tcx.local_def_id_to_hir_id(ty_impl_item.def_id.expect_local()),
+                tcx.def_span(ty_impl_item.def_id),
+                errors::UselessImplItem,
+            )
+        }
+
         check_specialization_validity(
             tcx,
             trait_def,
@@ -1044,7 +1079,11 @@ fn check_impl_items_against_trait<'tcx>(
                 .as_ref()
                 .is_some_and(|node_item| node_item.item.defaultness(tcx).has_value());
 
-            if !is_implemented && tcx.defaultness(impl_id).is_final() {
+            if !is_implemented
+                && tcx.defaultness(impl_id).is_final()
+                // unsized types don't need to implement methods that have `Self: Sized` bounds.
+                && !(self_is_guaranteed_unsized && tcx.generics_require_sized_self(trait_item_id))
+            {
                 missing_items.push(tcx.associated_item(trait_item_id));
             }
 

compiler/rustc_hir_analysis/src/errors.rs

@@ -908,6 +908,10 @@ pub(crate) enum ImplNotMarkedDefault {
     },
 }
 
+#[derive(LintDiagnostic)]
+#[diag(hir_analysis_useless_impl_item)]
+pub(crate) struct UselessImplItem;
+
 #[derive(Diagnostic)]
 #[diag(hir_analysis_missing_trait_item, code = E0046)]
 pub(crate) struct MissingTraitItem {

compiler/rustc_span/src/analyze_source_file.rs

@@ -68,21 +68,18 @@ cfg_match! {
 
             const CHUNK_SIZE: usize = 16;
 
-            let src_bytes = src.as_bytes();
-
-            let chunk_count = src.len() / CHUNK_SIZE;
+            let (chunks, tail) = src.as_bytes().as_chunks::<CHUNK_SIZE>();
 
             // This variable keeps track of where we should start decoding a
             // chunk. If a multi-byte character spans across chunk boundaries,
             // we need to skip that part in the next chunk because we already
             // handled it.
             let mut intra_chunk_offset = 0;
 
-            for chunk_index in 0..chunk_count {
-                let ptr = src_bytes.as_ptr() as *const __m128i;
+            for (chunk_index, chunk) in chunks.iter().enumerate() {
                 // We don't know if the pointer is aligned to 16 bytes, so we
                 // use `loadu`, which supports unaligned loading.
-                let chunk = unsafe { _mm_loadu_si128(ptr.add(chunk_index)) };
+                let chunk = unsafe { _mm_loadu_si128(chunk.as_ptr() as *const __m128i) };
 
                 // For character in the chunk, see if its byte value is < 0, which
                 // indicates that it's part of a UTF-8 char.
@@ -123,7 +120,7 @@ cfg_match! {
             }
 
             // There might still be a tail left to analyze
-            let tail_start = chunk_count * CHUNK_SIZE + intra_chunk_offset;
+            let tail_start = src.len() - tail.len() + intra_chunk_offset;
             if tail_start < src.len() {
                 analyze_source_file_generic(
                     &src[tail_start..],

compiler/rustc_span/src/lib.rs

@@ -31,6 +31,7 @@
 #![feature(round_char_boundary)]
 #![feature(rustc_attrs)]
 #![feature(rustdoc_internals)]
+#![feature(slice_as_chunks)]
 #![warn(unreachable_pub)]
 // tidy-alphabetical-end
 

library/Cargo.lock

@@ -61,9 +61,9 @@ dependencies = [
 
 [[package]]
 name = "compiler_builtins"
-version = "0.1.147"
+version = "0.1.148"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7170335a76fbcba350c3ea795c15df3b2c02934e35e502e82c4dd7837d4d0161"
+checksum = "26137996631d90d2727b905b480fdcf8c4479fdbce7afd7f8e3796d689b33cc2"
 dependencies = [
  "cc",
  "rustc-std-workspace-core",

library/alloc/Cargo.toml

@@ -12,7 +12,7 @@ edition = "2021"
 
 [dependencies]
 core = { path = "../core", public = true }
-compiler_builtins = { version = "=0.1.147", features = ['rustc-dep-of-std'] }
+compiler_builtins = { version = "=0.1.148", features = ['rustc-dep-of-std'] }
 
 [dev-dependencies]
 rand = { version = "0.9.0", default-features = false, features = ["alloc"] }

library/std/Cargo.toml

@@ -18,7 +18,7 @@ cfg-if = { version = "1.0", features = ['rustc-dep-of-std'] }
 panic_unwind = { path = "../panic_unwind", optional = true }
 panic_abort = { path = "../panic_abort" }
 core = { path = "../core", public = true }
-compiler_builtins = { version = "=0.1.147" }
+compiler_builtins = { version = "=0.1.148" }
 unwind = { path = "../unwind" }
 hashbrown = { version = "0.15", default-features = false, features = [
     'rustc-dep-of-std',

src/bootstrap/Cargo.lock

@@ -88,9 +88,9 @@ dependencies = [
 
 [[package]]
 name = "cc"
-version = "1.2.0"
+version = "1.1.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1aeb932158bd710538c73702db6945cb68a8fb08c519e6e12706b94263b36db8"
+checksum = "9540e661f81799159abee814118cc139a2004b3a3aa3ea37724a1b66530b90e0"
 dependencies = [
  "shlex",
 ]

src/bootstrap/Cargo.toml

@@ -37,7 +37,9 @@ test = false
 # Most of the time updating these dependencies requires modifications to the
 # bootstrap codebase(e.g., https://github.com/rust-lang/rust/issues/124565);
 # otherwise, some targets will fail. That's why these dependencies are explicitly pinned.
-cc = "=1.2.0"
+#
+# Do not upgrade this crate unless https://github.com/rust-lang/cc-rs/issues/1317 is fixed.
+cc = "=1.1.22"
 cmake = "=0.1.48"
 
 build_helper = { path = "../build_helper" }

src/bootstrap/src/core/build_steps/test.rs

@@ -293,17 +293,27 @@ impl Step for Cargo {
     }
 
     fn make_run(run: RunConfig<'_>) {
-        run.builder.ensure(Cargo { stage: run.builder.top_stage, host: run.target });
+        // If stage is explicitly set or not lower than 2, keep it. Otherwise, make sure it's at least 2
+        // as tests for this step don't work with a lower stage.
+        let stage = if run.builder.config.is_explicit_stage() || run.builder.top_stage >= 2 {
+            run.builder.top_stage
+        } else {
+            2
+        };
+
+        run.builder.ensure(Cargo { stage, host: run.target });
     }
 
     /// Runs `cargo test` for `cargo` packaged with Rust.
     fn run(self, builder: &Builder<'_>) {
-        if self.stage < 2 {
-            eprintln!("WARNING: cargo tests on stage {} may not behave well.", self.stage);
+        let stage = self.stage;
+
+        if stage < 2 {
+            eprintln!("WARNING: cargo tests on stage {stage} may not behave well.");
             eprintln!("HELP: consider using stage 2");
         }
 
-        let compiler = builder.compiler(self.stage, self.host);
+        let compiler = builder.compiler(stage, self.host);
 
         let cargo = builder.ensure(tool::Cargo { compiler, target: self.host });
         let compiler = cargo.build_compiler;
@@ -340,7 +350,7 @@ impl Step for Cargo {
                 crates: vec!["cargo".into()],
                 target: self.host.triple.to_string(),
                 host: self.host.triple.to_string(),
-                stage: self.stage,
+                stage,
             },
             builder,
         );
@@ -739,7 +749,15 @@ impl Step for Clippy {
     }
 
     fn make_run(run: RunConfig<'_>) {
-        run.builder.ensure(Clippy { stage: run.builder.top_stage, host: run.target });
+        // If stage is explicitly set or not lower than 2, keep it. Otherwise, make sure it's at least 2
+        // as tests for this step don't work with a lower stage.
+        let stage = if run.builder.config.is_explicit_stage() || run.builder.top_stage >= 2 {
+            run.builder.top_stage
+        } else {
+            2
+        };
+
+        run.builder.ensure(Clippy { stage, host: run.target });
     }
 
     /// Runs `cargo test` for clippy.

src/bootstrap/src/core/config/config.rs

@@ -218,6 +218,8 @@ pub struct Config {
     pub stderr_is_tty: bool,
 
     pub on_fail: Option<String>,
+    pub explicit_stage_from_cli: bool,
+    pub explicit_stage_from_config: bool,
     pub stage: u32,
     pub keep_stage: Vec<u32>,
     pub keep_stage_std: Vec<u32>,
@@ -2323,6 +2325,14 @@ impl Config {
         config.compiletest_diff_tool = compiletest_diff_tool;
 
         let download_rustc = config.download_rustc_commit.is_some();
+        config.explicit_stage_from_cli = flags.stage.is_some();
+        config.explicit_stage_from_config = test_stage.is_some()
+            || build_stage.is_some()
+            || doc_stage.is_some()
+            || dist_stage.is_some()
+            || install_stage.is_some()
+            || check_stage.is_some()
+            || bench_stage.is_some();
         // See https://github.com/rust-lang/compiler-team/issues/326
         config.stage = match config.cmd {
             Subcommand::Check { .. } => flags.stage.or(check_stage).unwrap_or(0),
@@ -2392,6 +2402,10 @@ impl Config {
         }
     }
 
+    pub fn is_explicit_stage(&self) -> bool {
+        self.explicit_stage_from_cli || self.explicit_stage_from_config
+    }
+
     /// Runs a command, printing out nice contextual information if it fails.
     /// Exits if the command failed to execute at all, otherwise returns its
     /// `status.success()`.

src/bootstrap/src/core/config/tests.rs

@@ -454,3 +454,64 @@ fn check_rustc_if_unchanged_paths() {
         assert!(config.src.join(p).exists(), "{p} doesn't exist.");
     }
 }
+
+#[test]
+fn test_explicit_stage() {
+    let config = Config::parse_inner(
+        Flags::parse(&["check".to_owned(), "--config=/does/not/exist".to_owned()]),
+        |&_| {
+            toml::from_str(
+                r#"
+            [build]
+            test-stage = 1
+        "#,
+            )
+        },
+    );
+
+    assert!(!config.explicit_stage_from_cli);
+    assert!(config.explicit_stage_from_config);
+    assert!(config.is_explicit_stage());
+
+    let config = Config::parse_inner(
+        Flags::parse(&[
+            "check".to_owned(),
+            "--stage=2".to_owned(),
+            "--config=/does/not/exist".to_owned(),
+        ]),
+        |&_| toml::from_str(""),
+    );
+
+    assert!(config.explicit_stage_from_cli);
+    assert!(!config.explicit_stage_from_config);
+    assert!(config.is_explicit_stage());
+
+    let config = Config::parse_inner(
+        Flags::parse(&[
+            "check".to_owned(),
+            "--stage=2".to_owned(),
+            "--config=/does/not/exist".to_owned(),
+        ]),
+        |&_| {
+            toml::from_str(
+                r#"
+            [build]
+            test-stage = 1
+        "#,
+            )
+        },
+    );
+
+    assert!(config.explicit_stage_from_cli);
+    assert!(config.explicit_stage_from_config);
+    assert!(config.is_explicit_stage());
+
+    let config = Config::parse_inner(
+        Flags::parse(&["check".to_owned(), "--config=/does/not/exist".to_owned()]),
+        |&_| toml::from_str(""),
+    );
+
+    assert!(!config.explicit_stage_from_cli);
+    assert!(!config.explicit_stage_from_config);
+    assert!(!config.is_explicit_stage());
+}

tests/ui/did_you_mean/recursion_limit_deref.stderr

@@ -1,3 +1,7 @@
+error: reached the recursion limit finding the struct tail for `K`
+   |
+   = help: consider increasing the recursion limit by adding a `#![recursion_limit = "20"]`
+
 error: reached the recursion limit finding the struct tail for `Bottom`
    |
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "20"]`
@@ -21,7 +25,7 @@ LL |     let x: &Bottom = &t;
    = note: expected reference `&Bottom`
               found reference `&Top`
 
-error: aborting due to 3 previous errors
+error: aborting due to 4 previous errors
 
 Some errors have detailed explanations: E0055, E0308.
 For more information about an error, try `rustc --explain E0055`.

tests/ui/invalid/issue-114435-layout-type-err.rs

@@ -1,6 +1,6 @@
-//@ build-fail
+//@ check-fail
 //@ compile-flags: --crate-type lib -Cdebuginfo=2
-//@ error-pattern: the type has an unknown layout
+//@ error-pattern: recursion limit
 
 #![recursion_limit = "10"]
 macro_rules! link {
@@ -28,7 +28,6 @@ impl Bottom {
     }
 }
 
-
 link!(A, B);
 link!(B, C);
 link!(C, D);
@@ -41,4 +40,4 @@ link!(I, J);
 link!(J, K);
 link!(K, Bottom);
 
-fn main() { }
+fn main() {}

tests/ui/invalid/issue-114435-layout-type-err.stderr

@@ -2,7 +2,5 @@ error: reached the recursion limit finding the struct tail for `Bottom`
    |
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "20"]`
 
-error: the type has an unknown layout
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error