Auto merge of #95974 - fee1-dead:rollup-2fr55cs, r=fee1-dead

Rollup of 5 pull requests

Successful merges:

 - #95671 (feat: Allow usage of sudo [while not accessing root] in x.py)
 - #95716 (sess: warn w/out fluent bundle w/ user sysroot)
 - #95820 (simplify const params diagnostic on stable)
 - #95900 (Fix documentation for wasm32-unknown-unknown)
 - #95947 (`impl const Default for Box<[T]>` and `Box<str>`)

Failed merges:

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

Author: bors

compiler/rustc_ast/src/lib.rs

@@ -9,6 +9,8 @@
     test(attr(deny(warnings)))
 )]
 #![feature(box_patterns)]
+#![feature(const_default_impls)]
+#![feature(const_trait_impl)]
 #![feature(crate_visibility_modifier)]
 #![feature(if_let_guard)]
 #![feature(label_break_value)]

compiler/rustc_ast/src/ptr.rs

@@ -128,14 +128,7 @@ impl<S: Encoder, T: Encodable<S>> Encodable<S> for P<T> {
 
 impl<T> P<[T]> {
     pub const fn new() -> P<[T]> {
-        // HACK(eddyb) bypass the lack of a `const fn` to create an empty `Box<[T]>`
-        // (as trait methods, `default` in this case, can't be `const fn` yet).
-        P {
-            ptr: unsafe {
-                use std::ptr::NonNull;
-                std::mem::transmute(NonNull::<[T; 0]>::dangling() as NonNull<[T]>)
-            },
-        }
+        P { ptr: Box::default() }
     }
 
     #[inline(never)]

compiler/rustc_error_messages/src/lib.rs

@@ -11,7 +11,7 @@ use std::error::Error;
 use std::fmt;
 use std::fs;
 use std::io;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 use tracing::{instrument, trace};
 
 #[cfg(parallel_compiler)]
@@ -45,7 +45,7 @@ pub enum TranslationBundleError {
     /// Failed to add `FluentResource` to `FluentBundle`.
     AddResource(FluentError),
     /// `$sysroot/share/locale/$locale` does not exist.
-    MissingLocale(io::Error),
+    MissingLocale,
     /// Cannot read directory entries of `$sysroot/share/locale/$locale`.
     ReadLocalesDir(io::Error),
     /// Cannot read directory entry of `$sysroot/share/locale/$locale`.
@@ -62,9 +62,7 @@ impl fmt::Display for TranslationBundleError {
                 write!(f, "could not parse ftl file: {}", e)
             }
             TranslationBundleError::AddResource(e) => write!(f, "failed to add resource: {}", e),
-            TranslationBundleError::MissingLocale(e) => {
-                write!(f, "missing locale directory: {}", e)
-            }
+            TranslationBundleError::MissingLocale => write!(f, "missing locale directory"),
             TranslationBundleError::ReadLocalesDir(e) => {
                 write!(f, "could not read locales dir: {}", e)
             }
@@ -84,7 +82,7 @@ impl Error for TranslationBundleError {
             TranslationBundleError::ReadFtl(e) => Some(e),
             TranslationBundleError::ParseFtl(e) => Some(e),
             TranslationBundleError::AddResource(e) => Some(e),
-            TranslationBundleError::MissingLocale(e) => Some(e),
+            TranslationBundleError::MissingLocale => None,
             TranslationBundleError::ReadLocalesDir(e) => Some(e),
             TranslationBundleError::ReadLocalesDirEntry(e) => Some(e),
             TranslationBundleError::LocaleIsNotDir => None,
@@ -113,7 +111,8 @@ impl From<Vec<FluentError>> for TranslationBundleError {
 /// (overriding any conflicting messages).
 #[instrument(level = "trace")]
 pub fn fluent_bundle(
-    sysroot: &Path,
+    mut user_provided_sysroot: Option<PathBuf>,
+    mut sysroot_candidates: Vec<PathBuf>,
     requested_locale: Option<LanguageIdentifier>,
     additional_ftl_path: Option<&Path>,
     with_directionality_markers: bool,
@@ -140,33 +139,43 @@ pub fn fluent_bundle(
 
     // If the user requests the default locale then don't try to load anything.
     if !requested_fallback_locale && let Some(requested_locale) = requested_locale {
-        let mut sysroot = sysroot.to_path_buf();
-        sysroot.push("share");
-        sysroot.push("locale");
-        sysroot.push(requested_locale.to_string());
-        trace!(?sysroot);
-
-        let _ = sysroot.try_exists().map_err(TranslationBundleError::MissingLocale)?;
-
-        if !sysroot.is_dir() {
-            return Err(TranslationBundleError::LocaleIsNotDir);
-        }
-
-        for entry in sysroot.read_dir().map_err(TranslationBundleError::ReadLocalesDir)? {
-            let entry = entry.map_err(TranslationBundleError::ReadLocalesDirEntry)?;
-            let path = entry.path();
-            trace!(?path);
-            if path.extension().and_then(|s| s.to_str()) != Some("ftl") {
+        let mut found_resources = false;
+        for sysroot in user_provided_sysroot.iter_mut().chain(sysroot_candidates.iter_mut()) {
+            sysroot.push("share");
+            sysroot.push("locale");
+            sysroot.push(requested_locale.to_string());
+            trace!(?sysroot);
+
+            if !sysroot.exists() {
                 trace!("skipping");
                 continue;
             }
 
-            let resource_str =
-                fs::read_to_string(path).map_err(TranslationBundleError::ReadFtl)?;
-            let resource =
-                FluentResource::try_new(resource_str).map_err(TranslationBundleError::from)?;
-            trace!(?resource);
-            bundle.add_resource(resource).map_err(TranslationBundleError::from)?;
+            if !sysroot.is_dir() {
+                return Err(TranslationBundleError::LocaleIsNotDir);
+            }
+
+            for entry in sysroot.read_dir().map_err(TranslationBundleError::ReadLocalesDir)? {
+                let entry = entry.map_err(TranslationBundleError::ReadLocalesDirEntry)?;
+                let path = entry.path();
+                trace!(?path);
+                if path.extension().and_then(|s| s.to_str()) != Some("ftl") {
+                    trace!("skipping");
+                    continue;
+                }
+
+                let resource_str =
+                    fs::read_to_string(path).map_err(TranslationBundleError::ReadFtl)?;
+                let resource =
+                    FluentResource::try_new(resource_str).map_err(TranslationBundleError::from)?;
+                trace!(?resource);
+                bundle.add_resource(resource).map_err(TranslationBundleError::from)?;
+                found_resources = true;
+            }
+        }
+
+        if !found_resources {
+            return Err(TranslationBundleError::MissingLocale);
         }
     }
 

compiler/rustc_interface/src/tests.rs

@@ -44,6 +44,7 @@ fn mk_session(matches: getopts::Matches) -> (Session, CfgSpecs) {
     let sess = build_session(
         sessopts,
         None,
+        None,
         registry,
         DiagnosticOutput::Default,
         Default::default(),

compiler/rustc_interface/src/util.rs

@@ -83,9 +83,23 @@ pub fn create_session(
     // target_override is documented to be called before init(), so this is okay
     let target_override = codegen_backend.target_override(&sopts);
 
+    let bundle = match rustc_errors::fluent_bundle(
+        sopts.maybe_sysroot.clone(),
+        sysroot_candidates(),
+        sopts.debugging_opts.translate_lang.clone(),
+        sopts.debugging_opts.translate_additional_ftl.as_deref(),
+        sopts.debugging_opts.translate_directionality_markers,
+    ) {
+        Ok(bundle) => bundle,
+        Err(e) => {
+            early_error(sopts.error_format, &format!("failed to load fluent bundle: {e}"));
+        }
+    };
+
     let mut sess = session::build_session(
         sopts,
         input_path,
+        bundle,
         descriptions,
         diagnostic_output,
         lint_caps,

compiler/rustc_session/src/session.rs

@@ -20,8 +20,8 @@ use rustc_errors::emitter::{Emitter, EmitterWriter, HumanReadableErrorType};
 use rustc_errors::json::JsonEmitter;
 use rustc_errors::registry::Registry;
 use rustc_errors::{
-    fallback_fluent_bundle, fluent_bundle, DiagnosticBuilder, DiagnosticId, DiagnosticMessage,
-    EmissionGuarantee, ErrorGuaranteed, FluentBundle, MultiSpan,
+    fallback_fluent_bundle, DiagnosticBuilder, DiagnosticId, DiagnosticMessage, EmissionGuarantee,
+    ErrorGuaranteed, FluentBundle, MultiSpan,
 };
 use rustc_macros::HashStable_Generic;
 pub use rustc_span::def_id::StableCrateId;
@@ -1162,6 +1162,7 @@ pub enum DiagnosticOutput {
 pub fn build_session(
     sopts: config::Options,
     local_crate_source_file: Option<PathBuf>,
+    bundle: Option<Lrc<rustc_errors::FluentBundle>>,
     registry: rustc_errors::registry::Registry,
     diagnostics_output: DiagnosticOutput,
     driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
@@ -1214,16 +1215,17 @@ pub fn build_session(
         hash_kind,
     ));
 
-    let bundle = fluent_bundle(
-        &sysroot,
-        sopts.debugging_opts.translate_lang.clone(),
-        sopts.debugging_opts.translate_additional_ftl.as_deref(),
-        sopts.debugging_opts.translate_directionality_markers,
-    )
-    .expect("failed to load fluent bundle");
     let fallback_bundle =
-        fallback_fluent_bundle(sopts.debugging_opts.translate_directionality_markers)
-            .expect("failed to load fallback fluent bundle");
+        match fallback_fluent_bundle(sopts.debugging_opts.translate_directionality_markers) {
+            Ok(bundle) => bundle,
+            Err(e) => {
+                early_error(
+                    sopts.error_format,
+                    &format!("failed to load fallback fluent bundle: {e}"),
+                );
+            }
+        };
+
     let emitter =
         default_emitter(&sopts, registry, source_map.clone(), bundle, fallback_bundle, write_dest);
 

compiler/rustc_typeck/src/check/wfcheck.rs

@@ -816,16 +816,69 @@ fn check_param_wf(tcx: TyCtxt<'_>, param: &hir::GenericParam<'_>) {
         hir::GenericParamKind::Const { ty: hir_ty, default: _ } => {
             let ty = tcx.type_of(tcx.hir().local_def_id(param.hir_id));
 
-            let err_ty_str;
-            let mut is_ptr = true;
-            let err = if tcx.features().adt_const_params {
-                match ty.peel_refs().kind() {
+            if tcx.features().adt_const_params {
+                let err = match ty.peel_refs().kind() {
                     ty::FnPtr(_) => Some("function pointers"),
                     ty::RawPtr(_) => Some("raw pointers"),
                     _ => None,
+                };
+
+                if let Some(unsupported_type) = err {
+                    tcx.sess.span_err(
+                        hir_ty.span,
+                        &format!(
+                            "using {} as const generic parameters is forbidden",
+                            unsupported_type
+                        ),
+                    );
+                }
+
+                if traits::search_for_structural_match_violation(param.span, tcx, ty).is_some() {
+                    // We use the same error code in both branches, because this is really the same
+                    // issue: we just special-case the message for type parameters to make it
+                    // clearer.
+                    if let ty::Param(_) = ty.peel_refs().kind() {
+                        // Const parameters may not have type parameters as their types,
+                        // because we cannot be sure that the type parameter derives `PartialEq`
+                        // and `Eq` (just implementing them is not enough for `structural_match`).
+                        struct_span_err!(
+                            tcx.sess,
+                            hir_ty.span,
+                            E0741,
+                            "`{}` is not guaranteed to `#[derive(PartialEq, Eq)]`, so may not be \
+                            used as the type of a const parameter",
+                            ty,
+                        )
+                        .span_label(
+                            hir_ty.span,
+                            format!("`{}` may not derive both `PartialEq` and `Eq`", ty),
+                        )
+                        .note(
+                            "it is not currently possible to use a type parameter as the type of a \
+                            const parameter",
+                        )
+                        .emit();
+                    } else {
+                        struct_span_err!(
+                            tcx.sess,
+                            hir_ty.span,
+                            E0741,
+                            "`{}` must be annotated with `#[derive(PartialEq, Eq)]` to be used as \
+                            the type of a const parameter",
+                            ty,
+                        )
+                        .span_label(
+                            hir_ty.span,
+                            format!("`{}` doesn't derive both `PartialEq` and `Eq`", ty),
+                        )
+                        .emit();
+                    }
                 }
             } else {
-                match ty.kind() {
+                let err_ty_str;
+                let mut is_ptr = true;
+
+                let err = match ty.kind() {
                     ty::Bool | ty::Char | ty::Int(_) | ty::Uint(_) | ty::Error(_) => None,
                     ty::FnPtr(_) => Some("function pointers"),
                     ty::RawPtr(_) => Some("raw pointers"),
@@ -834,74 +887,33 @@ fn check_param_wf(tcx: TyCtxt<'_>, param: &hir::GenericParam<'_>) {
                         err_ty_str = format!("`{}`", ty);
                         Some(err_ty_str.as_str())
                     }
-                }
-            };
-            if let Some(unsupported_type) = err {
-                if is_ptr {
-                    tcx.sess.span_err(
-                        hir_ty.span,
-                        &format!(
-                            "using {} as const generic parameters is forbidden",
-                            unsupported_type
-                        ),
-                    );
-                } else {
-                    let mut err = tcx.sess.struct_span_err(
-                        hir_ty.span,
-                        &format!(
-                            "{} is forbidden as the type of a const generic parameter",
-                            unsupported_type
-                        ),
-                    );
-                    err.note("the only supported types are integers, `bool` and `char`");
-                    if tcx.sess.is_nightly_build() {
-                        err.help(
+                };
+
+                if let Some(unsupported_type) = err {
+                    if is_ptr {
+                        tcx.sess.span_err(
+                            hir_ty.span,
+                            &format!(
+                                "using {} as const generic parameters is forbidden",
+                                unsupported_type
+                            ),
+                        );
+                    } else {
+                        let mut err = tcx.sess.struct_span_err(
+                            hir_ty.span,
+                            &format!(
+                                "{} is forbidden as the type of a const generic parameter",
+                                unsupported_type
+                            ),
+                        );
+                        err.note("the only supported types are integers, `bool` and `char`");
+                        if tcx.sess.is_nightly_build() {
+                            err.help(
                             "more complex types are supported with `#![feature(adt_const_params)]`",
                         );
+                        }
+                        err.emit();
                     }
-                    err.emit();
-                }
-            };
-
-            if traits::search_for_structural_match_violation(param.span, tcx, ty).is_some() {
-                // We use the same error code in both branches, because this is really the same
-                // issue: we just special-case the message for type parameters to make it
-                // clearer.
-                if let ty::Param(_) = ty.peel_refs().kind() {
-                    // Const parameters may not have type parameters as their types,
-                    // because we cannot be sure that the type parameter derives `PartialEq`
-                    // and `Eq` (just implementing them is not enough for `structural_match`).
-                    struct_span_err!(
-                        tcx.sess,
-                        hir_ty.span,
-                        E0741,
-                        "`{}` is not guaranteed to `#[derive(PartialEq, Eq)]`, so may not be \
-                            used as the type of a const parameter",
-                        ty,
-                    )
-                    .span_label(
-                        hir_ty.span,
-                        format!("`{}` may not derive both `PartialEq` and `Eq`", ty),
-                    )
-                    .note(
-                        "it is not currently possible to use a type parameter as the type of a \
-                            const parameter",
-                    )
-                    .emit();
-                } else {
-                    struct_span_err!(
-                        tcx.sess,
-                        hir_ty.span,
-                        E0741,
-                        "`{}` must be annotated with `#[derive(PartialEq, Eq)]` to be used as \
-                            the type of a const parameter",
-                        ty,
-                    )
-                    .span_label(
-                        hir_ty.span,
-                        format!("`{}` doesn't derive both `PartialEq` and `Eq`", ty),
-                    )
-                    .emit();
                 }
             }
         }