Auto merge of rust-lang#120448 - matthiaskrgr:rollup-j30dzmw, r=matthiaskrgr

Rollup of 8 pull requests

Successful merges:

 - rust-lang#116677 (References refer to allocated objects)
 - rust-lang#118533 (Suppress unhelpful diagnostics for unresolved top level attributes)
 - rust-lang#119991 (Reject infinitely-sized reads from io::Repeat)
 - rust-lang#120232 (Add support for custom JSON targets when using build-std.)
 - rust-lang#120358 (Bump Fuchsia, build tests, and use 8 core bots)
 - rust-lang#120424 (raw pointer metadata API: data address -> data pointer)
 - rust-lang#120434 (Revert outdated version of "Add the wasm32-wasi-preview2 target")
 - rust-lang#120443 (Fixes footnote handling in rustdoc)

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

Author: bors

.github/workflows/ci.yml

@@ -291,7 +291,7 @@ jobs:
           - name: x86_64-gnu-integration
             env:
               CI_ONLY_WHEN_CHANNEL: nightly
-            os: ubuntu-20.04-16core-64gb
+            os: ubuntu-20.04-8core-32gb
           - name: x86_64-gnu-debug
             os: ubuntu-20.04-8core-32gb
             env: {}

Cargo.lock

@@ -3004,11 +3004,11 @@ dependencies = [
 
 [[package]]
 name = "pulldown-cmark"
-version = "0.9.3"
+version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "77a1a2f1f0a7ecff9c31abbe177637be0e97a0aef46cf8738ece09327985d998"
+checksum = "80eb9f69aec5cd8828765a75f739383fbbe3e8b9d84370bde1cc90487700794a"
 dependencies = [
- "bitflags 1.3.2",
+ "bitflags 2.4.1",
  "memchr",
  "unicase",
 ]

compiler/rustc_errors/src/lib.rs

@@ -509,6 +509,7 @@ pub enum StashKey {
     MaybeForgetReturn,
     /// Query cycle detected, stashing in favor of a better error.
     Cycle,
+    UndeterminedMacroResolution,
 }
 
 fn default_track_diagnostic(diag: Diagnostic, f: &mut dyn FnMut(Diagnostic)) {

compiler/rustc_passes/src/check_attr.rs

@@ -5,8 +5,10 @@
 //! item.
 
 use crate::{errors, fluent_generated as fluent};
-use rustc_ast::{ast, AttrStyle, Attribute, LitKind, MetaItemKind, MetaItemLit, NestedMetaItem};
+use rustc_ast::{ast, AttrKind, AttrStyle, Attribute, LitKind};
+use rustc_ast::{MetaItemKind, MetaItemLit, NestedMetaItem};
 use rustc_data_structures::fx::FxHashMap;
+use rustc_errors::StashKey;
 use rustc_errors::{Applicability, DiagCtxt, IntoDiagnosticArg, MultiSpan};
 use rustc_feature::{AttributeDuplicates, AttributeType, BuiltinAttribute, BUILTIN_ATTRIBUTE_MAP};
 use rustc_hir as hir;
@@ -2530,6 +2532,14 @@ fn check_invalid_crate_level_attr(tcx: TyCtxt<'_>, attrs: &[Attribute]) {
         if attr.style == AttrStyle::Inner {
             for attr_to_check in ATTRS_TO_CHECK {
                 if attr.has_name(*attr_to_check) {
+                    if let AttrKind::Normal(ref p) = attr.kind
+                        && let Some(diag) = tcx.dcx().steal_diagnostic(
+                            p.item.path.span,
+                            StashKey::UndeterminedMacroResolution,
+                        )
+                    {
+                        diag.cancel();
+                    }
                     let item = tcx
                         .hir()
                         .items()

compiler/rustc_resolve/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2021"
 [dependencies]
 # tidy-alphabetical-start
 bitflags = "2.4.1"
-pulldown-cmark = { version = "0.9.3", default-features = false }
+pulldown-cmark = { version = "0.9.5", default-features = false }
 rustc_arena = { path = "../rustc_arena" }
 rustc_ast = { path = "../rustc_ast" }
 rustc_ast_pretty = { path = "../rustc_ast_pretty" }

compiler/rustc_resolve/src/macros.rs

@@ -1,10 +1,9 @@
 //! A bunch of methods and structures more or less related to resolving macros and
 //! interface provided by `Resolver` to macro expander.
 
-use crate::errors::{
-    self, AddAsNonDerive, CannotDetermineMacroResolution, CannotFindIdentInThisScope,
-    MacroExpectedFound, RemoveSurroundingDerive,
-};
+use crate::errors::CannotDetermineMacroResolution;
+use crate::errors::{self, AddAsNonDerive, CannotFindIdentInThisScope};
+use crate::errors::{MacroExpectedFound, RemoveSurroundingDerive};
 use crate::Namespace::*;
 use crate::{BuiltinMacroState, Determinacy, MacroData};
 use crate::{DeriveData, Finalize, ParentScope, ResolutionError, Resolver, ScopeSet};
@@ -15,6 +14,7 @@ use rustc_ast_pretty::pprust;
 use rustc_attr::StabilityLevel;
 use rustc_data_structures::intern::Interned;
 use rustc_data_structures::sync::Lrc;
+use rustc_errors::StashKey;
 use rustc_errors::{struct_span_code_err, Applicability};
 use rustc_expand::base::{Annotatable, DeriveResolutions, Indeterminate, ResolverExpand};
 use rustc_expand::base::{SyntaxExtension, SyntaxExtensionKind};
@@ -25,9 +25,8 @@ use rustc_hir::def_id::{CrateNum, DefId, LocalDefId};
 use rustc_middle::middle::stability;
 use rustc_middle::ty::RegisteredTools;
 use rustc_middle::ty::{TyCtxt, Visibility};
-use rustc_session::lint::builtin::{
-    LEGACY_DERIVE_HELPERS, SOFT_UNSTABLE, UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES,
-};
+use rustc_session::lint::builtin::UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES;
+use rustc_session::lint::builtin::{LEGACY_DERIVE_HELPERS, SOFT_UNSTABLE};
 use rustc_session::lint::builtin::{UNUSED_MACROS, UNUSED_MACRO_RULES};
 use rustc_session::lint::BuiltinLintDiagnostics;
 use rustc_session::parse::feature_err;
@@ -703,21 +702,21 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                     // situations should be reported as errors, so this is a bug.
                     this.dcx().span_delayed_bug(span, "inconsistent resolution for a macro");
                 }
-            } else {
+            } else if this.tcx.dcx().has_errors().is_none() && this.privacy_errors.is_empty() {
                 // It's possible that the macro was unresolved (indeterminate) and silently
                 // expanded into a dummy fragment for recovery during expansion.
                 // Now, post-expansion, the resolution may succeed, but we can't change the
                 // past and need to report an error.
                 // However, non-speculative `resolve_path` can successfully return private items
                 // even if speculative `resolve_path` returned nothing previously, so we skip this
-                // less informative error if the privacy error is reported elsewhere.
-                if this.privacy_errors.is_empty() {
-                    this.dcx().emit_err(CannotDetermineMacroResolution {
-                        span,
-                        kind: kind.descr(),
-                        path: Segment::names_to_string(path),
-                    });
-                }
+                // less informative error if no other error is reported elsewhere.
+
+                let err = this.dcx().create_err(CannotDetermineMacroResolution {
+                    span,
+                    kind: kind.descr(),
+                    path: Segment::names_to_string(path),
+                });
+                err.stash(span, StashKey::UndeterminedMacroResolution);
             }
         };
 

compiler/rustc_span/src/symbol.rs

@@ -1799,7 +1799,6 @@ symbols! {
         warn,
         wasm_abi,
         wasm_import_module,
-        wasm_preview2,
         wasm_target_feature,
         while_let,
         windows,

compiler/rustc_target/src/spec/mod.rs

@@ -1574,7 +1574,6 @@ supported_targets! {
     ("wasm32-unknown-emscripten", wasm32_unknown_emscripten),
     ("wasm32-unknown-unknown", wasm32_unknown_unknown),
     ("wasm32-wasi", wasm32_wasi),
-    ("wasm32-wasi-preview2", wasm32_wasi_preview2),
     ("wasm32-wasi-preview1-threads", wasm32_wasi_preview1_threads),
     ("wasm64-unknown-unknown", wasm64_unknown_unknown),
 

compiler/rustc_target/src/spec/targets/wasm32_wasi_preview1_threads.rs

@@ -72,12 +72,11 @@
 //! best we can with this target. Don't start relying on too much here unless
 //! you know what you're getting in to!
 
-use crate::spec::{base, crt_objects, cvs, Cc, LinkSelfContainedDefault, LinkerFlavor, Target};
+use crate::spec::{base, crt_objects, Cc, LinkSelfContainedDefault, LinkerFlavor, Target};
 
 pub fn target() -> Target {
     let mut options = base::wasm::options();
 
-    options.families = cvs!["wasm", "wasi"];
     options.os = "wasi".into();
 
     options.add_pre_link_args(

compiler/rustc_target/src/spec/targets/wasm32_wasi_preview2.rs

@@ -1384,6 +1384,30 @@ mod prim_usize {}
 /// work on references as well as they do on owned values! The implementations described here are
 /// meant for generic contexts, where the final type `T` is a type parameter or otherwise not
 /// locally known.
+///
+/// # Safety
+///
+/// For all types, `T: ?Sized`, and for all `t: &T` or `t: &mut T`, when such values cross an API
+/// boundary, the following invariants must generally be upheld:
+///
+/// * `t` is aligned to `align_of_val(t)`
+/// * `t` is dereferenceable for `size_of_val(t)` many bytes
+///
+/// If `t` points at address `a`, being "dereferenceable" for N bytes means that the memory range
+/// `[a, a + N)` is all contained within a single [allocated object].
+///
+/// For instance, this means that unsafe code in a safe function may assume these invariants are
+/// ensured of arguments passed by the caller, and it may assume that these invariants are ensured
+/// of return values from any safe functions it calls. In most cases, the inverse is also true:
+/// unsafe code must not violate these invariants when passing arguments to safe functions or
+/// returning values from safe functions; such violations may result in undefined behavior. Where
+/// exceptions to this latter requirement exist, they will be called out explicitly in documentation.
+///
+/// It is not decided yet whether unsafe code may violate these invariants temporarily on internal
+/// data. As a consequence, unsafe code which violates these invariants temporarily on internal data
+/// may become unsound in future versions of Rust depending on how this question is decided.
+///
+/// [allocated object]: ptr#allocated-object
 #[stable(feature = "rust1", since = "1.0.0")]
 mod prim_ref {}
 

library/core/src/primitive_docs.rs

@@ -285,7 +285,7 @@ impl<T: ?Sized> *const T {
         self.with_addr(f(self.addr()))
     }
 
-    /// Decompose a (possibly wide) pointer into its address and metadata components.
+    /// Decompose a (possibly wide) pointer into its data pointer and metadata components.
     ///
     /// The pointer can be later reconstructed with [`from_raw_parts`].
     #[unstable(feature = "ptr_metadata", issue = "81513")]

library/core/src/ptr/const_ptr.rs

@@ -39,13 +39,13 @@ use crate::hash::{Hash, Hasher};
 ///
 /// # Usage
 ///
-/// Raw pointers can be decomposed into the data address and metadata components
+/// Raw pointers can be decomposed into the data pointer and metadata components
 /// with their [`to_raw_parts`] method.
 ///
 /// Alternatively, metadata alone can be extracted with the [`metadata`] function.
 /// A reference can be passed to [`metadata`] and implicitly coerced.
 ///
-/// A (possibly-wide) pointer can be put back together from its address and metadata
+/// A (possibly-wide) pointer can be put back together from its data pointer and metadata
 /// with [`from_raw_parts`] or [`from_raw_parts_mut`].
 ///
 /// [`to_raw_parts`]: *const::to_raw_parts
@@ -98,7 +98,7 @@ pub const fn metadata<T: ?Sized>(ptr: *const T) -> <T as Pointee>::Metadata {
     unsafe { PtrRepr { const_ptr: ptr }.components.metadata }
 }
 
-/// Forms a (possibly-wide) raw pointer from a data address and metadata.
+/// Forms a (possibly-wide) raw pointer from a data pointer and metadata.
 ///
 /// This function is safe but the returned pointer is not necessarily safe to dereference.
 /// For slices, see the documentation of [`slice::from_raw_parts`] for safety requirements.
@@ -109,13 +109,13 @@ pub const fn metadata<T: ?Sized>(ptr: *const T) -> <T as Pointee>::Metadata {
 #[rustc_const_unstable(feature = "ptr_metadata", issue = "81513")]
 #[inline]
 pub const fn from_raw_parts<T: ?Sized>(
-    data_address: *const (),
+    data_pointer: *const (),
     metadata: <T as Pointee>::Metadata,
 ) -> *const T {
     // SAFETY: Accessing the value from the `PtrRepr` union is safe since *const T
     // and PtrComponents<T> have the same memory layouts. Only std can make this
     // guarantee.
-    unsafe { PtrRepr { components: PtrComponents { data_address, metadata } }.const_ptr }
+    unsafe { PtrRepr { components: PtrComponents { data_pointer, metadata } }.const_ptr }
 }
 
 /// Performs the same functionality as [`from_raw_parts`], except that a
@@ -126,13 +126,13 @@ pub const fn from_raw_parts<T: ?Sized>(
 #[rustc_const_unstable(feature = "ptr_metadata", issue = "81513")]
 #[inline]
 pub const fn from_raw_parts_mut<T: ?Sized>(
-    data_address: *mut (),
+    data_pointer: *mut (),
     metadata: <T as Pointee>::Metadata,
 ) -> *mut T {
     // SAFETY: Accessing the value from the `PtrRepr` union is safe since *const T
     // and PtrComponents<T> have the same memory layouts. Only std can make this
     // guarantee.
-    unsafe { PtrRepr { components: PtrComponents { data_address, metadata } }.mut_ptr }
+    unsafe { PtrRepr { components: PtrComponents { data_pointer, metadata } }.mut_ptr }
 }
 
 #[repr(C)]
@@ -144,7 +144,7 @@ union PtrRepr<T: ?Sized> {
 
 #[repr(C)]
 struct PtrComponents<T: ?Sized> {
-    data_address: *const (),
+    data_pointer: *const (),
     metadata: <T as Pointee>::Metadata,
 }
 

library/core/src/ptr/metadata.rs

@@ -292,7 +292,7 @@ impl<T: ?Sized> *mut T {
         self.with_addr(f(self.addr()))
     }
 
-    /// Decompose a (possibly wide) pointer into its address and metadata components.
+    /// Decompose a (possibly wide) pointer into its data pointer and metadata components.
     ///
     /// The pointer can be later reconstructed with [`from_raw_parts_mut`].
     #[unstable(feature = "ptr_metadata", issue = "81513")]

library/core/src/ptr/mut_ptr.rs

@@ -259,16 +259,16 @@ impl<T: ?Sized> NonNull<T> {
     #[rustc_const_unstable(feature = "ptr_metadata", issue = "81513")]
     #[inline]
     pub const fn from_raw_parts(
-        data_address: NonNull<()>,
+        data_pointer: NonNull<()>,
         metadata: <T as super::Pointee>::Metadata,
     ) -> NonNull<T> {
-        // SAFETY: The result of `ptr::from::raw_parts_mut` is non-null because `data_address` is.
+        // SAFETY: The result of `ptr::from::raw_parts_mut` is non-null because `data_pointer` is.
         unsafe {
-            NonNull::new_unchecked(super::from_raw_parts_mut(data_address.as_ptr(), metadata))
+            NonNull::new_unchecked(super::from_raw_parts_mut(data_pointer.as_ptr(), metadata))
         }
     }
 
-    /// Decompose a (possibly wide) pointer into its address and metadata components.
+    /// Decompose a (possibly wide) pointer into its data pointer and metadata components.
     ///
     /// The pointer can be later reconstructed with [`NonNull::from_raw_parts`].
     #[unstable(feature = "ptr_metadata", issue = "81513")]

library/core/src/ptr/non_null.rs

@@ -12,7 +12,8 @@ fn main() {
         return;
     }
 
-    let target = env::var("TARGET").expect("TARGET was not set");
+    let target_os = env::var("CARGO_CFG_TARGET_OS").expect("CARGO_CFG_TARGET_OS was not set");
+    let target_env = env::var("CARGO_CFG_TARGET_ENV").expect("CARGO_CFG_TARGET_ENV was not set");
     let cfg = &mut cc::Build::new();
 
     // FIXME: `rerun-if-changed` directives are not currently emitted and the build script
@@ -40,7 +41,7 @@ fn main() {
         "InstrProfilingBiasVar.c",
     ];
 
-    if target.contains("msvc") {
+    if target_env == "msvc" {
         // Don't pull in extra libraries on MSVC
         cfg.flag("/Zl");
         profile_sources.push("WindowsMMap.c");
@@ -55,7 +56,7 @@ fn main() {
         cfg.flag("-fno-builtin");
         cfg.flag("-fomit-frame-pointer");
         cfg.define("VISIBILITY_HIDDEN", None);
-        if !target.contains("windows") {
+        if target_os != "windows" {
             cfg.flag("-fvisibility=hidden");
             cfg.define("COMPILER_RT_HAS_UNAME", Some("1"));
         } else {