Auto merge of #85486 - RalfJung:rollup-4ibcxuu, r=RalfJung

Rollup of 8 pull requests

Successful merges:

 - #84717 (impl FromStr for proc_macro::Literal)
 - #85169 (Add method-toggle to <details> for methods)
 - #85287 (Expose `Concurrent` (private type in public i'face))
 - #85315 (adding time complexity for partition_in_place iter method)
 - #85439 (Add diagnostic item to `CStr`)
 - #85464 (Fix UB in documented example for `ptr::swap`)
 - #85470 (Fix invalid CSS rules for a:hover)
 - #85472 (CTFE Machine: do not expose Allocation)

Failed merges:

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

Author: bors

compiler/rustc_expand/src/proc_macro_server.rs

@@ -1,9 +1,7 @@
 use crate::base::{ExtCtxt, ResolverExpand};
 
 use rustc_ast as ast;
-use rustc_ast::token;
-use rustc_ast::token::Nonterminal;
-use rustc_ast::token::NtIdent;
+use rustc_ast::token::{self, Nonterminal, NtIdent, TokenKind};
 use rustc_ast::tokenstream::{self, CanSynthesizeMissingTokens};
 use rustc_ast::tokenstream::{DelimSpan, Spacing::*, TokenStream, TreeAndSpacing};
 use rustc_ast_pretty::pprust;
@@ -541,6 +539,33 @@ impl server::Ident for Rustc<'_> {
 }
 
 impl server::Literal for Rustc<'_> {
+    fn from_str(&mut self, s: &str) -> Result<Self::Literal, ()> {
+        let override_span = None;
+        let stream = parse_stream_from_source_str(
+            FileName::proc_macro_source_code(s),
+            s.to_owned(),
+            self.sess,
+            override_span,
+        );
+        if stream.len() != 1 {
+            return Err(());
+        }
+        let tree = stream.into_trees().next().unwrap();
+        let token = match tree {
+            tokenstream::TokenTree::Token(token) => token,
+            tokenstream::TokenTree::Delimited { .. } => return Err(()),
+        };
+        let span_data = token.span.data();
+        if (span_data.hi.0 - span_data.lo.0) as usize != s.len() {
+            // There is a comment or whitespace adjacent to the literal.
+            return Err(());
+        }
+        let lit = match token.kind {
+            TokenKind::Literal(lit) => lit,
+            _ => return Err(()),
+        };
+        Ok(Literal { lit, span: self.call_site })
+    }
     fn debug_kind(&mut self, literal: &Self::Literal) -> String {
         format!("{:?}", literal.lit.kind)
     }

compiler/rustc_mir/src/interpret/machine.rs

@@ -313,7 +313,7 @@ pub trait Machine<'mir, 'tcx>: Sized {
     #[inline(always)]
     fn memory_read(
         _memory_extra: &Self::MemoryExtra,
-        _alloc: &Allocation<Self::PointerTag, Self::AllocExtra>,
+        _alloc_extra: &Self::AllocExtra,
         _ptr: Pointer<Self::PointerTag>,
         _size: Size,
     ) -> InterpResult<'tcx> {
@@ -324,7 +324,7 @@ pub trait Machine<'mir, 'tcx>: Sized {
     #[inline(always)]
     fn memory_written(
         _memory_extra: &mut Self::MemoryExtra,
-        _alloc: &mut Allocation<Self::PointerTag, Self::AllocExtra>,
+        _alloc_extra: &mut Self::AllocExtra,
         _ptr: Pointer<Self::PointerTag>,
         _size: Size,
     ) -> InterpResult<'tcx> {
@@ -335,8 +335,9 @@ pub trait Machine<'mir, 'tcx>: Sized {
     #[inline(always)]
     fn memory_deallocated(
         _memory_extra: &mut Self::MemoryExtra,
-        _alloc: &mut Allocation<Self::PointerTag, Self::AllocExtra>,
+        _alloc_extra: &mut Self::AllocExtra,
         _ptr: Pointer<Self::PointerTag>,
+        _size: Size,
     ) -> InterpResult<'tcx> {
         Ok(())
     }

compiler/rustc_mir/src/interpret/memory.rs

@@ -343,10 +343,11 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> Memory<'mir, 'tcx, M> {
         }
 
         // Let the machine take some extra action
-        M::memory_deallocated(&mut self.extra, &mut alloc, ptr)?;
+        let size = alloc.size();
+        M::memory_deallocated(&mut self.extra, &mut alloc.extra, ptr, size)?;
 
         // Don't forget to remember size and align of this now-dead allocation
-        let old = self.dead_alloc_map.insert(ptr.alloc_id, (alloc.size(), alloc.align));
+        let old = self.dead_alloc_map.insert(ptr.alloc_id, (size, alloc.align));
         if old.is_some() {
             bug!("Nothing can be deallocated twice");
         }
@@ -591,7 +592,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> Memory<'mir, 'tcx, M> {
             },
         )?;
         if let Some((ptr, alloc)) = ptr_and_alloc {
-            M::memory_read(&self.extra, alloc, ptr, size)?;
+            M::memory_read(&self.extra, &alloc.extra, ptr, size)?;
             let range = alloc_range(ptr.offset, size);
             Ok(Some(AllocRef { alloc, range, tcx: self.tcx, alloc_id: ptr.alloc_id }))
         } else {
@@ -660,7 +661,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> Memory<'mir, 'tcx, M> {
             // FIXME: can we somehow avoid looking up the allocation twice here?
             // We cannot call `get_raw_mut` inside `check_and_deref_ptr` as that would duplicate `&mut self`.
             let (alloc, extra) = self.get_raw_mut(ptr.alloc_id)?;
-            M::memory_written(extra, alloc, ptr, size)?;
+            M::memory_written(extra, &mut alloc.extra, ptr, size)?;
             let range = alloc_range(ptr.offset, size);
             Ok(Some(AllocRefMut { alloc, range, tcx, alloc_id: ptr.alloc_id }))
         } else {
@@ -1029,7 +1030,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> Memory<'mir, 'tcx, M> {
             Some(src_ptr) => src_ptr,
         };
         let src_alloc = self.get_raw(src.alloc_id)?;
-        M::memory_read(&self.extra, src_alloc, src, size)?;
+        M::memory_read(&self.extra, &src_alloc.extra, src, size)?;
         // We need the `dest` ptr for the next operation, so we get it now.
         // We already did the source checks and called the hooks so we are good to return early.
         let dest = match dest {
@@ -1058,7 +1059,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> Memory<'mir, 'tcx, M> {
 
         // Destination alloc preparations and access hooks.
         let (dest_alloc, extra) = self.get_raw_mut(dest.alloc_id)?;
-        M::memory_written(extra, dest_alloc, dest, size * num_copies)?;
+        M::memory_written(extra, &mut dest_alloc.extra, dest, size * num_copies)?;
         let dest_bytes = dest_alloc
             .get_bytes_mut_ptr(&tcx, alloc_range(dest.offset, size * num_copies))
             .as_mut_ptr();

compiler/rustc_span/src/symbol.rs

@@ -132,6 +132,7 @@ symbols! {
         Borrow,
         Break,
         C,
+        CStr,
         CString,
         Center,
         Clone,

library/core/src/iter/traits/iterator.rs

@@ -1849,6 +1849,12 @@ pub trait Iterator {
     ///
     /// The relative order of partitioned items is not maintained.
     ///
+    /// # Current implementation
+    /// Current algorithms tries finding the first element for which the predicate evaluates
+    /// to false, and the last element for which it evaluates to true and repeatedly swaps them.
+    ///
+    /// Time Complexity: *O*(*N*)
+    ///
     /// See also [`is_partitioned()`] and [`partition()`].
     ///
     /// [`is_partitioned()`]: Iterator::is_partitioned

library/core/src/ptr/mod.rs

@@ -342,10 +342,12 @@ pub const fn slice_from_raw_parts_mut<T>(data: *mut T, len: usize) -> *mut [T] {
 /// ```
 /// use std::ptr;
 ///
-/// let mut array = [0, 1, 2, 3];
+/// let mut array: [i32; 4] = [0, 1, 2, 3];
+///
+/// let array_ptr: *mut i32 = array.as_mut_ptr();
 ///
-/// let x = array[0..].as_mut_ptr() as *mut [u32; 3]; // this is `array[0..3]`
-/// let y = array[1..].as_mut_ptr() as *mut [u32; 3]; // this is `array[1..4]`
+/// let x = array_ptr as *mut [i32; 3]; // this is `array[0..3]`
+/// let y = unsafe { array_ptr.add(1) } as *mut [i32; 3]; // this is `array[1..4]`
 ///
 /// unsafe {
 ///     ptr::swap(x, y);

library/proc_macro/src/bridge/mod.rs

@@ -107,6 +107,7 @@ macro_rules! with_api {
             Literal {
                 fn drop($self: $S::Literal);
                 fn clone($self: &$S::Literal) -> $S::Literal;
+                fn from_str(s: &str) -> Result<$S::Literal, ()>;
                 fn debug_kind($self: &$S::Literal) -> String;
                 fn symbol($self: &$S::Literal) -> String;
                 fn suffix($self: &$S::Literal) -> Option<String>;
@@ -315,6 +316,19 @@ impl<T: Unmark> Unmark for Option<T> {
     }
 }
 
+impl<T: Mark, E: Mark> Mark for Result<T, E> {
+    type Unmarked = Result<T::Unmarked, E::Unmarked>;
+    fn mark(unmarked: Self::Unmarked) -> Self {
+        unmarked.map(T::mark).map_err(E::mark)
+    }
+}
+impl<T: Unmark, E: Unmark> Unmark for Result<T, E> {
+    type Unmarked = Result<T::Unmarked, E::Unmarked>;
+    fn unmark(self) -> Self::Unmarked {
+        self.map(T::unmark).map_err(E::unmark)
+    }
+}
+
 macro_rules! mark_noop {
     ($($ty:ty),* $(,)?) => {
         $(

library/proc_macro/src/lib.rs

@@ -91,6 +91,12 @@ pub struct LexError {
     _inner: (),
 }
 
+impl LexError {
+    fn new() -> Self {
+        LexError { _inner: () }
+    }
+}
+
 #[stable(feature = "proc_macro_lexerror_impls", since = "1.44.0")]
 impl fmt::Display for LexError {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
@@ -1171,6 +1177,28 @@ impl Literal {
     }
 }
 
+/// Parse a single literal from its stringified representation.
+///
+/// In order to parse successfully, the input string must not contain anything
+/// but the literal token. Specifically, it must not contain whitespace or
+/// comments in addition to the literal.
+///
+/// The resulting literal token will have a `Span::call_site()` span.
+///
+/// NOTE: some errors may cause panics instead of returning `LexError`. We
+/// reserve the right to change these errors into `LexError`s later.
+#[stable(feature = "proc_macro_literal_parse", since = "1.54.0")]
+impl FromStr for Literal {
+    type Err = LexError;
+
+    fn from_str(src: &str) -> Result<Self, LexError> {
+        match bridge::client::Literal::from_str(src) {
+            Ok(literal) => Ok(Literal(literal)),
+            Err(()) => Err(LexError::new()),
+        }
+    }
+}
+
 // N.B., the bridge only provides `to_string`, implement `fmt::Display`
 // based on it (the reverse of the usual relationship between the two).
 #[stable(feature = "proc_macro_lib", since = "1.15.0")]

library/std/src/ffi/c_str.rs

@@ -185,6 +185,7 @@ pub struct CString {
 ///
 /// [`&str`]: prim@str
 #[derive(Hash)]
+#[cfg_attr(not(test), rustc_diagnostic_item = "CStr")]
 #[stable(feature = "rust1", since = "1.0.0")]
 // FIXME:
 // `fn from` in `impl From<&CStr> for Box<CStr>` current implementation relies

library/test/src/lib.rs

@@ -49,7 +49,7 @@ pub mod test {
         cli::{parse_opts, TestOpts},
         filter_tests,
         helpers::metrics::{Metric, MetricMap},
-        options::{Options, RunIgnored, RunStrategy, ShouldPanic},
+        options::{Concurrent, Options, RunIgnored, RunStrategy, ShouldPanic},
         run_test, test_main, test_main_static,
         test_result::{TestResult, TrFailed, TrFailedMsg, TrIgnored, TrOk},
         time::{TestExecTime, TestTimeOptions},