Auto merge of rust-lang#102926 - matthiaskrgr:rollup-oe2cdzj, r=matthiaskrgr

Rollup of 11 pull requests

Successful merges:

 - rust-lang#100387 (Check uniqueness of impl items by trait item when applicable.)
 - rust-lang#101727 (Stabilize map_first_last)
 - rust-lang#101774 (Warn about safety of `fetch_update`)
 - rust-lang#102227 (fs::get_path solarish version.)
 - rust-lang#102445 (Add `is_empty()` method to `core::ffi::CStr`.)
 - rust-lang#102612 (Migrate `codegen_ssa` to diagnostics structs - [Part 1])
 - rust-lang#102685 (Interpret EH actions properly)
 - rust-lang#102869 (Add basename and dirname aliases)
 - rust-lang#102889 (rustc_hir: Less error-prone methods for accessing `PartialRes` resolution)
 - rust-lang#102893 (Fix ICE rust-lang#102878)
 - rust-lang#102912 (:arrow_up: rust-analyzer)

Failed merges:

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

Author: bors

compiler/rustc_ast_lowering/src/asm.rs

@@ -205,13 +205,10 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                         let static_def_id = self
                             .resolver
                             .get_partial_res(sym.id)
-                            .filter(|res| res.unresolved_segments() == 0)
-                            .and_then(|res| {
-                                if let Res::Def(DefKind::Static(_), def_id) = res.base_res() {
-                                    Some(def_id)
-                                } else {
-                                    None
-                                }
+                            .and_then(|res| res.full_res())
+                            .and_then(|res| match res {
+                                Res::Def(DefKind::Static(_), def_id) => Some(def_id),
+                                _ => None,
                             });
 
                         if let Some(def_id) = static_def_id {

compiler/rustc_ast_lowering/src/expr.rs

@@ -1044,9 +1044,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         if let ExprKind::Path(qself, path) = &expr.kind {
             // Does the path resolve to something disallowed in a tuple struct/variant pattern?
             if let Some(partial_res) = self.resolver.get_partial_res(expr.id) {
-                if partial_res.unresolved_segments() == 0
-                    && !partial_res.base_res().expected_in_tuple_struct_pat()
-                {
+                if let Some(res) = partial_res.full_res() && !res.expected_in_tuple_struct_pat() {
                     return None;
                 }
             }
@@ -1066,9 +1064,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         if let ExprKind::Path(qself, path) = &expr.kind {
             // Does the path resolve to something disallowed in a unit struct/variant pattern?
             if let Some(partial_res) = self.resolver.get_partial_res(expr.id) {
-                if partial_res.unresolved_segments() == 0
-                    && !partial_res.base_res().expected_in_unit_struct_pat()
-                {
+                if let Some(res) = partial_res.full_res() && !res.expected_in_unit_struct_pat() {
                     return None;
                 }
             }

compiler/rustc_ast_lowering/src/item.rs

@@ -947,7 +947,10 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 }
                 AssocItemKind::MacCall(..) => unimplemented!(),
             },
-            trait_item_def_id: self.resolver.get_partial_res(i.id).map(|r| r.base_res().def_id()),
+            trait_item_def_id: self
+                .resolver
+                .get_partial_res(i.id)
+                .map(|r| r.expect_full_res().def_id()),
         }
     }
 
@@ -1349,9 +1352,9 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 match self
                     .resolver
                     .get_partial_res(bound_pred.bounded_ty.id)
-                    .map(|d| (d.base_res(), d.unresolved_segments()))
+                    .and_then(|r| r.full_res())
                 {
-                    Some((Res::Def(DefKind::TyParam, def_id), 0))
+                    Some(Res::Def(DefKind::TyParam, def_id))
                         if bound_pred.bound_generic_params.is_empty() =>
                     {
                         generics

compiler/rustc_ast_lowering/src/lib.rs

@@ -175,12 +175,7 @@ impl ResolverAstLoweringExt for ResolverAstLowering {
                 return None;
             }
 
-            let partial_res = self.partial_res_map.get(&expr.id)?;
-            if partial_res.unresolved_segments() != 0 {
-                return None;
-            }
-
-            if let Res::Def(DefKind::Fn, def_id) = partial_res.base_res() {
+            if let Res::Def(DefKind::Fn, def_id) = self.partial_res_map.get(&expr.id)?.full_res()? {
                 // We only support cross-crate argument rewriting. Uses
                 // within the same crate should be updated to use the new
                 // const generics style.
@@ -753,12 +748,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
     }
 
     fn expect_full_res(&mut self, id: NodeId) -> Res<NodeId> {
-        self.resolver.get_partial_res(id).map_or(Res::Err, |pr| {
-            if pr.unresolved_segments() != 0 {
-                panic!("path not fully resolved: {:?}", pr);
-            }
-            pr.base_res()
-        })
+        self.resolver.get_partial_res(id).map_or(Res::Err, |pr| pr.expect_full_res())
     }
 
     fn expect_full_res_from_use(&mut self, id: NodeId) -> impl Iterator<Item = Res<NodeId>> {
@@ -1138,8 +1128,11 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                     // type and value namespaces. If we resolved the path in the value namespace, we
                     // transform it into a generic const argument.
                     TyKind::Path(ref qself, ref path) => {
-                        if let Some(partial_res) = self.resolver.get_partial_res(ty.id) {
-                            let res = partial_res.base_res();
+                        if let Some(res) = self
+                            .resolver
+                            .get_partial_res(ty.id)
+                            .and_then(|partial_res| partial_res.full_res())
+                        {
                             if !res.matches_ns(Namespace::TypeNS) {
                                 debug!(
                                     "lower_generic_arg: Lowering type argument as const argument: {:?}",
@@ -1206,8 +1199,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         // by `ty_path`.
         if qself.is_none()
             && let Some(partial_res) = self.resolver.get_partial_res(t.id)
-            && partial_res.unresolved_segments() == 0
-            && let Res::Def(DefKind::Trait | DefKind::TraitAlias, _) = partial_res.base_res()
+            && let Some(Res::Def(DefKind::Trait | DefKind::TraitAlias, _)) = partial_res.full_res()
         {
             let (bounds, lifetime_bound) = self.with_dyn_type_scope(true, |this| {
                 let poly_trait_ref = this.ast_arena.ptr.alloc(PolyTraitRef {

compiler/rustc_ast_lowering/src/pat.rs

@@ -239,7 +239,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         ident: Ident,
         lower_sub: impl FnOnce(&mut Self) -> Option<&'hir hir::Pat<'hir>>,
     ) -> hir::PatKind<'hir> {
-        match self.resolver.get_partial_res(p.id).map(|d| d.base_res()) {
+        match self.resolver.get_partial_res(p.id).map(|d| d.expect_full_res()) {
             // `None` can occur in body-less function signatures
             res @ (None | Some(Res::Local(_))) => {
                 let canonical_id = match res {

compiler/rustc_ast_lowering/src/path.rs

@@ -29,11 +29,13 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
 
         let partial_res =
             self.resolver.get_partial_res(id).unwrap_or_else(|| PartialRes::new(Res::Err));
+        let base_res = partial_res.base_res();
+        let unresolved_segments = partial_res.unresolved_segments();
 
         let path_span_lo = p.span.shrink_to_lo();
-        let proj_start = p.segments.len() - partial_res.unresolved_segments();
+        let proj_start = p.segments.len() - unresolved_segments;
         let path = self.arena.alloc(hir::Path {
-            res: self.lower_res(partial_res.base_res()),
+            res: self.lower_res(base_res),
             segments: self.arena.alloc_from_iter(p.segments[..proj_start].iter().enumerate().map(
                 |(i, segment)| {
                     let param_mode = match (qself_position, param_mode) {
@@ -46,7 +48,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                         _ => param_mode,
                     };
 
-                    let parenthesized_generic_args = match partial_res.base_res() {
+                    let parenthesized_generic_args = match base_res {
                         // `a::b::Trait(Args)`
                         Res::Def(DefKind::Trait, _) if i + 1 == proj_start => {
                             ParenthesizedGenericArgs::Ok
@@ -83,7 +85,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
 
         // Simple case, either no projections, or only fully-qualified.
         // E.g., `std::mem::size_of` or `<I as Iterator>::Item`.
-        if partial_res.unresolved_segments() == 0 {
+        if unresolved_segments == 0 {
             return hir::QPath::Resolved(qself, path);
         }
 

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -31,7 +31,9 @@ use super::command::Command;
 use super::linker::{self, Linker};
 use super::metadata::{create_rmeta_file, MetadataPosition};
 use super::rpath::{self, RPathConfig};
-use crate::{looks_like_rust_object_file, CodegenResults, CompiledModule, CrateInfo, NativeLib};
+use crate::{
+    errors, looks_like_rust_object_file, CodegenResults, CompiledModule, CrateInfo, NativeLib,
+};
 
 use cc::windows_registry;
 use regex::Regex;
@@ -93,7 +95,7 @@ pub fn link_binary<'a>(
             let tmpdir = TempFileBuilder::new()
                 .prefix("rustc")
                 .tempdir()
-                .unwrap_or_else(|err| sess.fatal(&format!("couldn't create a temp dir: {}", err)));
+                .unwrap_or_else(|error| sess.emit_fatal(errors::CreateTempDir { error }));
             let path = MaybeTempDir::new(tmpdir, sess.opts.cg.save_temps);
             let out_filename = out_filename(
                 sess,
@@ -208,7 +210,7 @@ pub fn link_binary<'a>(
 pub fn each_linked_rlib(
     info: &CrateInfo,
     f: &mut dyn FnMut(CrateNum, &Path),
-) -> Result<(), String> {
+) -> Result<(), errors::LinkRlibError> {
     let crates = info.used_crates.iter();
     let mut fmts = None;
     for (ty, list) in info.dependency_formats.iter() {
@@ -224,26 +226,23 @@ pub fn each_linked_rlib(
         }
     }
     let Some(fmts) = fmts else {
-        return Err("could not find formats for rlibs".to_string());
+        return Err(errors::LinkRlibError::MissingFormat);
     };
     for &cnum in crates {
         match fmts.get(cnum.as_usize() - 1) {
             Some(&Linkage::NotLinked | &Linkage::IncludedFromDylib) => continue,
             Some(_) => {}
-            None => return Err("could not find formats for rlibs".to_string()),
+            None => return Err(errors::LinkRlibError::MissingFormat),
         }
-        let name = info.crate_name[&cnum];
+        let crate_name = info.crate_name[&cnum];
         let used_crate_source = &info.used_crate_source[&cnum];
         if let Some((path, _)) = &used_crate_source.rlib {
             f(cnum, &path);
         } else {
             if used_crate_source.rmeta.is_some() {
-                return Err(format!(
-                    "could not find rlib for: `{}`, found rmeta (metadata) file",
-                    name
-                ));
+                return Err(errors::LinkRlibError::OnlyRmetaFound { crate_name });
             } else {
-                return Err(format!("could not find rlib for: `{}`", name));
+                return Err(errors::LinkRlibError::NotFound { crate_name });
             }
         }
     }
@@ -340,10 +339,7 @@ fn link_rlib<'a>(
                 // -whole-archive and it isn't clear how we can currently handle such a
                 // situation correctly.
                 // See https://github.com/rust-lang/rust/issues/88085#issuecomment-901050897
-                sess.err(
-                    "the linking modifiers `+bundle` and `+whole-archive` are not compatible \
-                        with each other when generating rlibs",
-                );
+                sess.emit_err(errors::IncompatibleLinkingModifiers);
             }
             NativeLibKind::Static { bundle: None | Some(true), .. } => {}
             NativeLibKind::Static { bundle: Some(false), .. }
@@ -365,12 +361,8 @@ fn link_rlib<'a>(
                 ));
                 continue;
             }
-            ab.add_archive(&location, Box::new(|_| false)).unwrap_or_else(|e| {
-                sess.fatal(&format!(
-                    "failed to add native library {}: {}",
-                    location.to_string_lossy(),
-                    e
-                ));
+            ab.add_archive(&location, Box::new(|_| false)).unwrap_or_else(|error| {
+                sess.emit_fatal(errors::AddNativeLibrary { library_path: location, error });
             });
         }
     }
@@ -385,8 +377,8 @@ fn link_rlib<'a>(
             tmpdir.as_ref(),
         );
 
-        ab.add_archive(&output_path, Box::new(|_| false)).unwrap_or_else(|e| {
-            sess.fatal(&format!("failed to add native library {}: {}", output_path.display(), e));
+        ab.add_archive(&output_path, Box::new(|_| false)).unwrap_or_else(|error| {
+            sess.emit_fatal(errors::AddNativeLibrary { library_path: output_path, error });
         });
     }
 
@@ -451,14 +443,11 @@ fn collate_raw_dylibs(
                     // FIXME: when we add support for ordinals, figure out if we need to do anything
                     // if we have two DllImport values with the same name but different ordinals.
                     if import.calling_convention != old_import.calling_convention {
-                        sess.span_err(
-                            import.span,
-                            &format!(
-                                "multiple declarations of external function `{}` from \
-                                 library `{}` have different calling conventions",
-                                import.name, name,
-                            ),
-                        );
+                        sess.emit_err(errors::MultipleExternalFuncDecl {
+                            span: import.span,
+                            function: import.name,
+                            library_name: &name,
+                        });
                     }
                 }
             }
@@ -560,7 +549,7 @@ fn link_staticlib<'a>(
         all_native_libs.extend(codegen_results.crate_info.native_libraries[&cnum].iter().cloned());
     });
     if let Err(e) = res {
-        sess.fatal(&e);
+        sess.emit_fatal(e);
     }
 
     ab.build(out_filename);
@@ -673,9 +662,7 @@ fn link_dwarf_object<'a>(
     }) {
         Ok(()) => {}
         Err(e) => {
-            sess.struct_err("linking dwarf objects with thorin failed")
-                .note(&format!("{:?}", e))
-                .emit();
+            sess.emit_err(errors::ThorinErrorWrapper(e));
             sess.abort_if_errors();
         }
     }
@@ -879,23 +866,14 @@ fn link_natively<'a>(
                 let mut output = prog.stderr.clone();
                 output.extend_from_slice(&prog.stdout);
                 let escaped_output = escape_string(&output);
-                let mut err = sess.struct_err(&format!(
-                    "linking with `{}` failed: {}",
-                    linker_path.display(),
-                    prog.status
-                ));
-                err.note(&format!("{:?}", &cmd)).note(&escaped_output);
-                if escaped_output.contains("undefined reference to") {
-                    err.help(
-                        "some `extern` functions couldn't be found; some native libraries may \
-                         need to be installed or have their path specified",
-                    );
-                    err.note("use the `-l` flag to specify native libraries to link");
-                    err.note("use the `cargo:rustc-link-lib` directive to specify the native \
-                              libraries to link with Cargo (see https://doc.rust-lang.org/cargo/reference/build-scripts.html#cargorustc-link-libkindname)");
-                }
-                err.emit();
-
+                // FIXME: Add UI tests for this error.
+                let err = errors::LinkingFailed {
+                    linker_path: &linker_path,
+                    exit_status: prog.status,
+                    command: &cmd,
+                    escaped_output: &escaped_output,
+                };
+                sess.diagnostic().emit_err(err);
                 // If MSVC's `link.exe` was expected but the return code
                 // is not a Microsoft LNK error then suggest a way to fix or
                 // install the Visual Studio build tools.