Auto merge of #62782 - Mark-Simulacrum:rollup-1hz5ya6, r=Mark-Simulacrum

Rollup of 15 pull requests

Successful merges:

 - #61926 (Fix hyperlinks in From impls between Vec and VecDeque)
 - #62615 ( Only error about MSVC + PGO + unwind if we're generating code)
 - #62696 (Check that trait is exported or public before adding hint)
 - #62712 (Update the help message on error for self type)
 - #62728 (Fix repeated wording in slice documentation)
 - #62730 (Consolidate hygiene tests)
 - #62732 (Remove last use of mem::uninitialized from std::io::util)
 - #62740 (Add missing link to Infallible in TryFrom doc)
 - #62745 (update data_layout and features for armv7-wrs-vxworks)
 - #62749 (Document link_section arbitrary bytes)
 - #62752 (Disable Z3 in LLVM build)
 - #62764 (normalize use of backticks in compiler messages for librustc/lint)
 - #62774 (Disable simd_select_bitmask test on big endian)
 - #62777 (Self-referencial type now called a recursive type)
 - #62778 (Emit artifact notifications for dependency files)

Failed merges:

 - #62746 ( do not use mem::uninitialized in std::io)

r? @ghost

src/bootstrap/native.rs

@@ -150,6 +150,7 @@ impl Step for Llvm {
            .define("WITH_POLLY", "OFF")
            .define("LLVM_ENABLE_TERMINFO", "OFF")
            .define("LLVM_ENABLE_LIBEDIT", "OFF")
+           .define("LLVM_ENABLE_Z3_SOLVER", "OFF")
            .define("LLVM_PARALLEL_COMPILE_JOBS", builder.jobs().to_string())
            .define("LLVM_TARGET_ARCH", target.split('-').next().unwrap())
            .define("LLVM_DEFAULT_TARGET_TRIPLE", target);

src/liballoc/collections/vec_deque.rs

@@ -2721,6 +2721,9 @@ impl<T: fmt::Debug> fmt::Debug for VecDeque<T> {
 impl<T> From<Vec<T>> for VecDeque<T> {
     /// Turn a [`Vec<T>`] into a [`VecDeque<T>`].
     ///
+    /// [`Vec<T>`]: crate::vec::Vec
+    /// [`VecDeque<T>`]: crate::collections::VecDeque
+    ///
     /// This avoids reallocating where possible, but the conditions for that are
     /// strict, and subject to change, and so shouldn't be relied upon unless the
     /// `Vec<T>` came from `From<VecDeque<T>>` and hasn't been reallocated.
@@ -2752,6 +2755,9 @@ impl<T> From<Vec<T>> for VecDeque<T> {
 impl<T> From<VecDeque<T>> for Vec<T> {
     /// Turn a [`VecDeque<T>`] into a [`Vec<T>`].
     ///
+    /// [`Vec<T>`]: crate::vec::Vec
+    /// [`VecDeque<T>`]: crate::collections::VecDeque
+    ///
     /// This never needs to re-allocate, but does need to do O(n) data movement if
     /// the circular buffer doesn't happen to be at the beginning of the allocation.
     ///

src/libcore/convert.rs

@@ -477,6 +477,7 @@ pub trait TryInto<T>: Sized {
 /// [`TryInto`]: trait.TryInto.html
 /// [`i32::MAX`]: ../../std/i32/constant.MAX.html
 /// [`!`]: ../../std/primitive.never.html
+/// [`Infallible`]: enum.Infallible.html
 #[stable(feature = "try_from", since = "1.34.0")]
 pub trait TryFrom<T>: Sized {
     /// The type returned in the event of a conversion error.

src/libcore/slice/mod.rs

@@ -611,7 +611,7 @@ impl<T> [T] {
     ///
     /// See [`chunks_exact`] for a variant of this iterator that returns chunks of always exactly
     /// `chunk_size` elements, and [`rchunks`] for the same iterator but starting at the end of the
-    /// slice of the slice.
+    /// slice.
     ///
     /// # Panics
     ///
@@ -645,7 +645,7 @@ impl<T> [T] {
     ///
     /// See [`chunks_exact_mut`] for a variant of this iterator that returns chunks of always
     /// exactly `chunk_size` elements, and [`rchunks_mut`] for the same iterator but starting at
-    /// the end of the slice of the slice.
+    /// the end of the slice.
     ///
     /// # Panics
     ///
@@ -727,7 +727,7 @@ impl<T> [T] {
     ///
     /// See [`chunks_mut`] for a variant of this iterator that also returns the remainder as a
     /// smaller chunk, and [`rchunks_exact_mut`] for the same iterator but starting at the end of
-    /// the slice of the slice.
+    /// the slice.
     ///
     /// # Panics
     ///

src/librustc/lint/builtin.rs

@@ -94,19 +94,19 @@ declare_lint! {
 declare_lint! {
     pub UNUSED_FEATURES,
     Warn,
-    "unused features found in crate-level #[feature] directives"
+    "unused features found in crate-level `#[feature]` directives"
 }
 
 declare_lint! {
     pub STABLE_FEATURES,
     Warn,
-    "stable features found in #[feature] directive"
+    "stable features found in `#[feature]` directive"
 }
 
 declare_lint! {
     pub UNKNOWN_CRATE_TYPES,
     Deny,
-    "unknown crate type found in #[crate_type] directive"
+    "unknown crate type found in `#[crate_type]` directive"
 }
 
 declare_lint! {

src/librustc/lint/mod.rs

@@ -671,7 +671,7 @@ pub fn struct_lint_level<'a>(sess: &'a Session,
             sess.diag_note_once(
                 &mut err,
                 DiagnosticMessageId::from(lint),
-                &format!("#[{}({})] on by default", level.as_str(), name));
+                &format!("`#[{}({})]` on by default", level.as_str(), name));
         }
         LintSource::CommandLine(lint_flag_val) => {
             let flag = match level {
@@ -706,7 +706,7 @@ pub fn struct_lint_level<'a>(sess: &'a Session,
             if lint_attr_name.as_str() != name {
                 let level_str = level.as_str();
                 sess.diag_note_once(&mut err, DiagnosticMessageId::from(lint),
-                                    &format!("#[{}({})] implied by #[{}({})]",
+                                    &format!("`#[{}({})]` implied by `#[{}({})]`",
                                              level_str, name, level_str, lint_attr_name));
             }
         }

src/librustc/session/mod.rs

@@ -9,7 +9,7 @@ use crate::lint;
 use crate::lint::builtin::BuiltinLintDiagnostics;
 use crate::middle::allocator::AllocatorKind;
 use crate::middle::dependency_format;
-use crate::session::config::{OutputType, SwitchWithOptPath};
+use crate::session::config::{OutputType, PrintRequest, SwitchWithOptPath};
 use crate::session::search_paths::{PathKind, SearchPath};
 use crate::util::nodemap::{FxHashMap, FxHashSet};
 use crate::util::common::{duration_to_secs_str, ErrorReported};
@@ -1303,15 +1303,18 @@ fn validate_commandline_args_with_session_available(sess: &Session) {
     }
 
     // PGO does not work reliably with panic=unwind on Windows. Let's make it
-    // a warning to combine the two for now. It always runs into an assertions
+    // an error to combine the two for now. It always runs into an assertions
     // if LLVM is built with assertions, but without assertions it sometimes
     // does not crash and will probably generate a corrupted binary.
+    // We should only display this error if we're actually going to run PGO.
+    // If we're just supposed to print out some data, don't show the error (#61002).
     if sess.opts.cg.profile_generate.enabled() &&
        sess.target.target.options.is_like_msvc &&
-       sess.panic_strategy() == PanicStrategy::Unwind {
-        sess.warn("Profile-guided optimization does not yet work in conjunction \
-                   with `-Cpanic=unwind` on Windows when targeting MSVC. \
-                   See https://github.com/rust-lang/rust/issues/61002 for details.");
+       sess.panic_strategy() == PanicStrategy::Unwind &&
+       sess.opts.prints.iter().all(|&p| p == PrintRequest::NativeStaticLibs) {
+        sess.err("Profile-guided optimization does not yet work in conjunction \
+                  with `-Cpanic=unwind` on Windows when targeting MSVC. \
+                  See https://github.com/rust-lang/rust/issues/61002 for details.");
     }
 }
 

src/librustc/traits/specialize/mod.rs

@@ -366,8 +366,13 @@ pub(super) fn specialization_graph_provider(
                     }
                 }
 
-                for cause in &overlap.intercrate_ambiguity_causes {
-                    cause.add_intercrate_ambiguity_hint(&mut err);
+                let access_levels = tcx.privacy_access_levels(impl_def_id.krate);
+                if let Some(id) = tcx.hir().as_local_hir_id(impl_def_id) {
+                    if access_levels.is_exported(id) || access_levels.is_public(id) {
+                        for cause in &overlap.intercrate_ambiguity_causes {
+                            cause.add_intercrate_ambiguity_hint(&mut err);
+                        }
+                    }
                 }
 
                 if overlap.involves_placeholder {

src/librustc_interface/passes.rs

@@ -688,12 +688,20 @@ fn write_out_deps(sess: &Session, outputs: &OutputFilenames, out_filenames: &[Pa
         Ok(())
     })();
 
-    if let Err(e) = result {
-        sess.fatal(&format!(
-            "error writing dependencies to `{}`: {}",
-            deps_filename.display(),
-            e
-        ));
+    match result {
+        Ok(_) => {
+            if sess.opts.debugging_opts.emit_artifact_notifications {
+                 sess.parse_sess.span_diagnostic
+                    .emit_artifact_notification(&deps_filename, "dep-info");
+            }
+        },
+        Err(e) => {
+            sess.fatal(&format!(
+                "error writing dependencies to `{}`: {}",
+                deps_filename.display(),
+                e
+            ))
+        }
     }
 }
 

src/librustc_target/spec/arm_wrs_vxworks.rs

@@ -10,7 +10,7 @@ pub fn target() -> TargetResult {
         target_endian: "little".to_string(),
         target_pointer_width: "32".to_string(),
         target_c_int_width: "32".to_string(),
-        data_layout: "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
+        data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
         target_os: "vxworks".to_string(),
         target_env: "gnu".to_string(),
@@ -19,12 +19,11 @@ pub fn target() -> TargetResult {
 
         options: TargetOptions {
             // Info about features at https://wiki.debian.org/ArmHardFloatPort
-            features: "+v7,+vfp3,+d16,+thumb2,-neon".to_string(),
+            features: "+v7,+vfp3,-d32,+thumb2,-neon".to_string(),
             cpu: "generic".to_string(),
             max_atomic_width: Some(64),
             abi_blacklist: super::arm_base::abi_blacklist(),
             target_mcount: "\u{1}__gnu_mcount_nc".to_string(),
-//          tls_model: "local-exec".to_string(),
             position_independent_executables: false,
             .. base
         }

src/librustc_target/spec/armv7_wrs_vxworks.rs

@@ -10,7 +10,7 @@ pub fn target() -> TargetResult {
         target_endian: "little".to_string(),
         target_pointer_width: "32".to_string(),
         target_c_int_width: "32".to_string(),
-        data_layout: "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
+        data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
         arch: "arm".to_string(),
         target_os: "vxworks".to_string(),
         target_env: "gnu".to_string(),
@@ -19,12 +19,11 @@ pub fn target() -> TargetResult {
 
         options: TargetOptions {
             // Info about features at https://wiki.debian.org/ArmHardFloatPort
-            features: "+v7,+vfp3,+d16,+thumb2,-neon".to_string(),
+            features: "+v7,+vfp3,-d32,+thumb2,-neon".to_string(),
             cpu: "generic".to_string(),
             max_atomic_width: Some(64),
             abi_blacklist: super::arm_base::abi_blacklist(),
             target_mcount: "\u{1}__gnu_mcount_nc".to_string(),
-//          tls_model: "local-exec".to_string(),
             position_independent_executables: false,
             .. base
         }

src/librustc_typeck/check/mod.rs

@@ -1321,7 +1321,7 @@ fn check_opaque<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, substs: SubstsRef<'tcx>,
             tcx.sess, span, E0720,
             "opaque type expands to a recursive type",
         );
-        err.span_label(span, "expands to self-referential type");
+        err.span_label(span, "expands to a recursive type");
         if let ty::Opaque(..) = partially_expanded_type.sty {
             err.note("type resolves to itself");
         } else {
@@ -1442,11 +1442,14 @@ fn maybe_check_static_with_link_section(tcx: TyCtxt<'_>, id: DefId, span: Span)
         return
     }
 
-    // For the wasm32 target statics with #[link_section] are placed into custom
+    // For the wasm32 target statics with `#[link_section]` are placed into custom
     // sections of the final output file, but this isn't link custom sections of
     // other executable formats. Namely we can only embed a list of bytes,
     // nothing with pointers to anything else or relocations. If any relocation
     // show up, reject them here.
+    // `#[link_section]` may contain arbitrary, or even undefined bytes, but it is
+    // the consumer's responsibility to ensure all bytes that have been read
+    // have defined values.
     let instance = ty::Instance::mono(tcx, id);
     let cid = GlobalId {
         instance,

src/librustc_typeck/check/wfcheck.rs

@@ -769,6 +769,10 @@ fn check_method_receiver<'fcx, 'tcx>(
     method: &ty::AssocItem,
     self_ty: Ty<'tcx>,
 ) {
+    const HELP_FOR_SELF_TYPE: &str =
+        "consider changing to `self`, `&self`, `&mut self`, `self: Box<Self>`, \
+         `self: Rc<Self>`, `self: Arc<Self>`, or `self: Pin<P>` (where P is one \
+         of the previous types except `Self`)";
     // Check that the method has a valid receiver type, given the type `Self`.
     debug!("check_method_receiver({:?}, self_ty={:?})",
            method, self_ty);
@@ -805,7 +809,7 @@ fn check_method_receiver<'fcx, 'tcx>(
             fcx.tcx.sess.diagnostic().mut_span_err(
                 span, &format!("invalid method receiver type: {:?}", receiver_ty)
             ).note("type of `self` must be `Self` or a type that dereferences to it")
-            .help("consider changing to `self`, `&self`, `&mut self`, or `self: Box<Self>`")
+            .help(HELP_FOR_SELF_TYPE)
             .code(DiagnosticId::Error("E0307".into()))
             .emit();
         }
@@ -823,14 +827,14 @@ fn check_method_receiver<'fcx, 'tcx>(
                             the `arbitrary_self_types` feature",
                         receiver_ty,
                     ),
-                ).help("consider changing to `self`, `&self`, `&mut self`, or `self: Box<Self>`")
+                ).help(HELP_FOR_SELF_TYPE)
                 .emit();
             } else {
                 // Report error; would not have worked with `arbitrary_self_types`.
                 fcx.tcx.sess.diagnostic().mut_span_err(
                     span, &format!("invalid method receiver type: {:?}", receiver_ty)
                 ).note("type must be `Self` or a type that dereferences to it")
-                .help("consider changing to `self`, `&self`, `&mut self`, or `self: Box<Self>`")
+                .help(HELP_FOR_SELF_TYPE)
                 .code(DiagnosticId::Error("E0307".into()))
                 .emit();
             }

src/libstd/io/util.rs

@@ -44,10 +44,15 @@ pub fn copy<R: ?Sized, W: ?Sized>(reader: &mut R, writer: &mut W) -> io::Result<
     where R: Read, W: Write
 {
     let mut buf = unsafe {
-        #[allow(deprecated)]
-        let mut buf: [u8; super::DEFAULT_BUF_SIZE] = mem::uninitialized();
-        reader.initializer().initialize(&mut buf);
-        buf
+        // This is still technically undefined behavior due to creating a reference
+        // to uninitialized data, but within libstd we can rely on more guarantees
+        // than if this code were in an external lib
+
+        // FIXME: This should probably be changed to an array of `MaybeUninit<u8>`
+        // once the `mem::MaybeUninit` slice APIs stabilize
+        let mut buf: mem::MaybeUninit<[u8; super::DEFAULT_BUF_SIZE]> = mem::MaybeUninit::uninit();
+        reader.initializer().initialize(&mut *buf.as_mut_ptr());
+        buf.assume_init()
     };
 
     let mut written = 0;

src/test/run-pass/extern/extern-prelude-core.stderr

@@ -4,5 +4,5 @@ warning: the feature `extern_prelude` has been stable since 1.30.0 and no longer
 LL | #![feature(extern_prelude, lang_items, start)]
    |            ^^^^^^^^^^^^^^
    |
-   = note: #[warn(stable_features)] on by default
+   = note: `#[warn(stable_features)]` on by default
 

src/test/run-pass/extern/extern-prelude-std.stderr

@@ -4,5 +4,5 @@ warning: the feature `extern_prelude` has been stable since 1.30.0 and no longer
 LL | #![feature(extern_prelude)]
    |            ^^^^^^^^^^^^^^
    |
-   = note: #[warn(stable_features)] on by default
+   = note: `#[warn(stable_features)]` on by default
 

src/test/run-pass/if-ret.stderr

@@ -4,5 +4,5 @@ warning: unreachable block in `if` expression
 LL | fn foo() { if (return) { } }
    |                        ^^^
    |
-   = note: #[warn(unreachable_code)] on by default
+   = note: `#[warn(unreachable_code)]` on by default
 

src/test/run-pass/macros/macro-use-all-and-none.stderr

@@ -4,5 +4,5 @@ warning: unused attribute
 LL | #[macro_use()]
    | ^^^^^^^^^^^^^^
    |
-   = note: #[warn(unused_attributes)] on by default
+   = note: `#[warn(unused_attributes)]` on by default
 

src/test/run-pass/rfcs/rfc-2126-crate-paths/crate-path-absolute.stderr

@@ -4,5 +4,5 @@ warning: the feature `crate_in_paths` has been stable since 1.30.0 and no longer
 LL | #![feature(crate_in_paths)]
    |            ^^^^^^^^^^^^^^
    |
-   = note: #[warn(stable_features)] on by default
+   = note: `#[warn(stable_features)]` on by default
 

src/test/run-pass/rfcs/rfc-2126-crate-paths/crate-path-visibility-ambiguity.stderr

@@ -4,5 +4,5 @@ warning: the feature `crate_in_paths` has been stable since 1.30.0 and no longer
 LL | #![feature(crate_in_paths)]
    |            ^^^^^^^^^^^^^^
    |
-   = note: #[warn(stable_features)] on by default
+   = note: `#[warn(stable_features)]` on by default
 

src/test/run-pass/simd/simd-intrinsic-generic-select.rs

@@ -2,6 +2,10 @@
 #![allow(non_camel_case_types)]
 
 // ignore-emscripten
+// ignore-mips       behavior of simd_select_bitmask is endian-specific
+// ignore-mips64     behavior of simd_select_bitmask is endian-specific
+// ignore-powerpc    behavior of simd_select_bitmask is endian-specific
+// ignore-powerpc64  behavior of simd_select_bitmask is endian-specific
 
 // Test that the simd_select intrinsics produces correct results.
 

src/test/rustdoc-ui/intra-links-warning-crlf.stderr

@@ -4,7 +4,7 @@ warning: `[error]` cannot be resolved, ignoring it...
 LL | /// [error]
    |      ^^^^^ cannot be resolved, ignoring
    |
-   = note: #[warn(intra_doc_link_resolution_failure)] on by default
+   = note: `#[warn(intra_doc_link_resolution_failure)]` on by default
    = help: to escape `[` and `]` characters, just add '\' before them like `\[` or `\]`
 
 warning: `[error1]` cannot be resolved, ignoring it...