Auto merge of #89179 - the8472:rollup-moxrtaj, r=the8472

Rollup of 8 pull requests

Successful merges:

 - #89036 (Fix missing `no_global_oom_handling` cfg-gating)
 - #89041 (Work around invalid DWARF bugs for fat LTO)
 - #89046 ("Fix" an overflow in byte position math)
 - #89127 (Re-enable the `src/test/debuginfo/mutex.rs` test on Windows)
 - #89133 (Fix ICE with `--cap-lints=allow` and `-Zfuel=...=0`)
 - #89162 (rustc_index: Add some map-like APIs to `IndexVec`)
 - #89164 (Document `--show-type-layout` in the rustdoc book)
 - #89170 (Disable the leak sanitizer on Macos aarch64 for now)

Failed merges:

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

compiler/rustc_ast_lowering/src/item.rs

@@ -474,9 +474,10 @@ impl<'hir> LoweringContext<'_, 'hir> {
                         res
                     } else {
                         // Associate an HirId to both ids even if there is no resolution.
-                        self.node_id_to_hir_id.ensure_contains_elem(new_node_id, || None);
-                        debug_assert!(self.node_id_to_hir_id[new_node_id].is_none());
-                        self.node_id_to_hir_id[new_node_id] = Some(hir::HirId::make_owner(new_id));
+                        let _old = self
+                            .node_id_to_hir_id
+                            .insert(new_node_id, hir::HirId::make_owner(new_id));
+                        debug_assert!(_old.is_none());
                         continue;
                     };
                     let ident = *ident;

compiler/rustc_ast_lowering/src/lib.rs

@@ -469,11 +469,8 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         let def_id = self.resolver.local_def_id(owner);
 
         // Always allocate the first `HirId` for the owner itself.
-        self.node_id_to_hir_id.ensure_contains_elem(owner, || None);
-        if let Some(_lowered) = self.node_id_to_hir_id[owner] {
-            panic!("with_hir_id_owner must not be called multiple times on owner {:?}", def_id);
-        }
-        self.node_id_to_hir_id[owner] = Some(hir::HirId::make_owner(def_id));
+        let _old = self.node_id_to_hir_id.insert(owner, hir::HirId::make_owner(def_id));
+        debug_assert_eq!(_old, None);
 
         let current_owner = std::mem::replace(&mut self.current_hir_id_owner, def_id);
         let current_local_counter =
@@ -484,8 +481,8 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         self.current_hir_id_owner = current_owner;
         self.item_local_id_counter = current_local_counter;
 
-        self.owners.ensure_contains_elem(def_id, || None);
-        self.owners[def_id] = Some(item);
+        let _old = self.owners.insert(def_id, item);
+        debug_assert!(_old.is_none());
 
         def_id
     }
@@ -499,18 +496,13 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
     fn lower_node_id(&mut self, ast_node_id: NodeId) -> hir::HirId {
         assert_ne!(ast_node_id, DUMMY_NODE_ID);
 
-        self.node_id_to_hir_id.ensure_contains_elem(ast_node_id, || None);
-        if let Some(existing_hir_id) = self.node_id_to_hir_id[ast_node_id] {
-            existing_hir_id
-        } else {
+        *self.node_id_to_hir_id.get_or_insert_with(ast_node_id, || {
             // Generate a new `HirId`.
             let owner = self.current_hir_id_owner;
             let local_id = self.item_local_id_counter;
             self.item_local_id_counter.increment_by(1);
-            let hir_id = hir::HirId { owner, local_id };
-            self.node_id_to_hir_id[ast_node_id] = Some(hir_id);
-            hir_id
-        }
+            hir::HirId { owner, local_id }
+        })
     }
 
     fn next_id(&mut self) -> hir::HirId {

compiler/rustc_codegen_llvm/src/back/lto.rs

@@ -325,6 +325,20 @@ fn fat_lto(
         drop(linker);
         save_temp_bitcode(&cgcx, &module, "lto.input");
 
+        // Fat LTO also suffers from the invalid DWARF issue similar to Thin LTO.
+        // Here we rewrite all `DICompileUnit` pointers if there is only one `DICompileUnit`.
+        // This only works around the problem when codegen-units = 1.
+        // Refer to the comments in the `optimize_thin_module` function for more details.
+        let mut cu1 = ptr::null_mut();
+        let mut cu2 = ptr::null_mut();
+        unsafe { llvm::LLVMRustLTOGetDICompileUnit(llmod, &mut cu1, &mut cu2) };
+        if !cu2.is_null() {
+            let _timer =
+                cgcx.prof.generic_activity_with_arg("LLVM_fat_lto_patch_debuginfo", &*module.name);
+            unsafe { llvm::LLVMRustLTOPatchDICompileUnit(llmod, cu1) };
+            save_temp_bitcode(cgcx, &module, "fat-lto-after-patch");
+        }
+
         // Internalize everything below threshold to help strip out more modules and such.
         unsafe {
             let ptr = symbols_below_threshold.as_ptr();
@@ -748,7 +762,7 @@ pub unsafe fn optimize_thin_module(
         // an error.
         let mut cu1 = ptr::null_mut();
         let mut cu2 = ptr::null_mut();
-        llvm::LLVMRustThinLTOGetDICompileUnit(llmod, &mut cu1, &mut cu2);
+        llvm::LLVMRustLTOGetDICompileUnit(llmod, &mut cu1, &mut cu2);
         if !cu2.is_null() {
             let msg = "multiple source DICompileUnits found";
             return Err(write::llvm_err(&diag_handler, msg));
@@ -847,7 +861,7 @@ pub unsafe fn optimize_thin_module(
             let _timer = cgcx
                 .prof
                 .generic_activity_with_arg("LLVM_thin_lto_patch_debuginfo", thin_module.name());
-            llvm::LLVMRustThinLTOPatchDICompileUnit(llmod, cu1);
+            llvm::LLVMRustLTOPatchDICompileUnit(llmod, cu1);
             save_temp_bitcode(cgcx, &module, "thin-lto-after-patch");
         }
 

compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -2377,12 +2377,8 @@ extern "C" {
         len: usize,
         out_len: &mut usize,
     ) -> *const u8;
-    pub fn LLVMRustThinLTOGetDICompileUnit(
-        M: &Module,
-        CU1: &mut *mut c_void,
-        CU2: &mut *mut c_void,
-    );
-    pub fn LLVMRustThinLTOPatchDICompileUnit(M: &Module, CU: *mut c_void);
+    pub fn LLVMRustLTOGetDICompileUnit(M: &Module, CU1: &mut *mut c_void, CU2: &mut *mut c_void);
+    pub fn LLVMRustLTOPatchDICompileUnit(M: &Module, CU: *mut c_void);
 
     pub fn LLVMRustLinkerNew(M: &'a Module) -> &'a mut Linker<'a>;
     pub fn LLVMRustLinkerAdd(

compiler/rustc_errors/src/lib.rs

@@ -13,9 +13,11 @@
 #[macro_use]
 extern crate rustc_macros;
 
+#[macro_use]
+extern crate tracing;
+
 pub use emitter::ColorConfig;
 
-use tracing::debug;
 use Level::*;
 
 use emitter::{is_case_difference, Emitter, EmitterWriter};

compiler/rustc_index/src/bit_set.rs

@@ -1072,13 +1072,9 @@ impl<R: Idx, C: Idx> SparseBitMatrix<R, C> {
     }
 
     fn ensure_row(&mut self, row: R) -> &mut HybridBitSet<C> {
-        // Instantiate any missing rows up to and including row `row` with an
-        // empty HybridBitSet.
-        self.rows.ensure_contains_elem(row, || None);
-
+        // Instantiate any missing rows up to and including row `row` with an empty HybridBitSet.
         // Then replace row `row` with a full HybridBitSet if necessary.
-        let num_columns = self.num_columns;
-        self.rows[row].get_or_insert_with(|| HybridBitSet::new_empty(num_columns))
+        self.rows.get_or_insert_with(row, || HybridBitSet::new_empty(self.num_columns))
     }
 
     /// Sets the cell at `(row, column)` to true. Put another way, insert

compiler/rustc_index/src/vec.rs

@@ -720,6 +720,21 @@ impl<I: Idx, T> IndexVec<I, T> {
     }
 }
 
+/// `IndexVec` is often used as a map, so it provides some map-like APIs.
+impl<I: Idx, T> IndexVec<I, Option<T>> {
+    #[inline]
+    pub fn insert(&mut self, index: I, value: T) -> Option<T> {
+        self.ensure_contains_elem(index, || None);
+        self[index].replace(value)
+    }
+
+    #[inline]
+    pub fn get_or_insert_with(&mut self, index: I, value: impl FnOnce() -> T) -> &mut T {
+        self.ensure_contains_elem(index, || None);
+        self[index].get_or_insert_with(value)
+    }
+}
+
 impl<I: Idx, T: Clone> IndexVec<I, T> {
     #[inline]
     pub fn resize(&mut self, new_len: usize, value: T) {

compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp

@@ -1747,7 +1747,7 @@ LLVMRustGetBitcodeSliceFromObjectData(const char *data,
 // Rewrite all `DICompileUnit` pointers to the `DICompileUnit` specified. See
 // the comment in `back/lto.rs` for why this exists.
 extern "C" void
-LLVMRustThinLTOGetDICompileUnit(LLVMModuleRef Mod,
+LLVMRustLTOGetDICompileUnit(LLVMModuleRef Mod,
                                 DICompileUnit **A,
                                 DICompileUnit **B) {
   Module *M = unwrap(Mod);
@@ -1765,7 +1765,7 @@ LLVMRustThinLTOGetDICompileUnit(LLVMModuleRef Mod,
 // Rewrite all `DICompileUnit` pointers to the `DICompileUnit` specified. See
 // the comment in `back/lto.rs` for why this exists.
 extern "C" void
-LLVMRustThinLTOPatchDICompileUnit(LLVMModuleRef Mod, DICompileUnit *Unit) {
+LLVMRustLTOPatchDICompileUnit(LLVMModuleRef Mod, DICompileUnit *Unit) {
   Module *M = unwrap(Mod);
 
   // If the original source module didn't have a `DICompileUnit` then try to

compiler/rustc_parse/src/lib.rs

@@ -6,6 +6,9 @@
 #![feature(box_patterns)]
 #![recursion_limit = "256"]
 
+#[macro_use]
+extern crate tracing;
+
 use rustc_ast as ast;
 use rustc_ast::token::{self, Nonterminal, Token, TokenKind};
 use rustc_ast::tokenstream::{self, AttributesData, CanSynthesizeMissingTokens, LazyTokenStream};

compiler/rustc_parse/src/parser/expr.rs

@@ -1084,6 +1084,7 @@ impl<'a> Parser<'a> {
 
     /// If we encounter a parser state that looks like the user has written a `struct` literal with
     /// parentheses instead of braces, recover the parser state and provide suggestions.
+    #[instrument(skip(self, seq, snapshot), level = "trace")]
     fn maybe_recover_struct_lit_bad_delims(
         &mut self,
         lo: Span,

compiler/rustc_session/src/session.rs

@@ -902,7 +902,12 @@ impl Session {
                 let mut fuel = self.optimization_fuel.lock();
                 ret = fuel.remaining != 0;
                 if fuel.remaining == 0 && !fuel.out_of_fuel {
-                    self.warn(&format!("optimization-fuel-exhausted: {}", msg()));
+                    if self.diagnostic().can_emit_warnings() {
+                        // We only call `msg` in case we can actually emit warnings.
+                        // Otherwise, this could cause a `delay_good_path_bug` to
+                        // trigger (issue #79546).
+                        self.warn(&format!("optimization-fuel-exhausted: {}", msg()));
+                    }
                     fuel.out_of_fuel = true;
                 } else if fuel.remaining > 0 {
                     fuel.remaining -= 1;

compiler/rustc_span/src/lib.rs

@@ -25,6 +25,9 @@
 #[macro_use]
 extern crate rustc_macros;
 
+#[macro_use]
+extern crate tracing;
+
 use rustc_data_structures::AtomicRef;
 use rustc_macros::HashStable_Generic;
 use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
@@ -782,13 +785,30 @@ impl Span {
     ///     ^^^^^^^^^^^^^^^^^
     /// ```
     pub fn until(self, end: Span) -> Span {
-        let span = self.data();
-        let end = end.data();
+        // Most of this function's body is copied from `to`.
+        // We can't just do `self.to(end.shrink_to_lo())`,
+        // because to also does some magic where it uses min/max so
+        // it can handle overlapping spans. Some advanced mis-use of
+        // `until` with different ctxts makes this visible.
+        let span_data = self.data();
+        let end_data = end.data();
+        // FIXME(jseyfried): `self.ctxt` should always equal `end.ctxt` here (cf. issue #23480).
+        // Return the macro span on its own to avoid weird diagnostic output. It is preferable to
+        // have an incomplete span than a completely nonsensical one.
+        if span_data.ctxt != end_data.ctxt {
+            if span_data.ctxt == SyntaxContext::root() {
+                return end;
+            } else if end_data.ctxt == SyntaxContext::root() {
+                return self;
+            }
+            // Both spans fall within a macro.
+            // FIXME(estebank): check if it is the *same* macro.
+        }
         Span::new(
-            span.lo,
-            end.lo,
-            if end.ctxt == SyntaxContext::root() { end.ctxt } else { span.ctxt },
-            if span.parent == end.parent { span.parent } else { None },
+            span_data.lo,
+            end_data.lo,
+            if end_data.ctxt == SyntaxContext::root() { end_data.ctxt } else { span_data.ctxt },
+            if span_data.parent == end_data.parent { span_data.parent } else { None },
         )
     }
 

compiler/rustc_span/src/source_map.rs

@@ -474,11 +474,12 @@ impl SourceMap {
         f.lookup_line(sp.lo()) != f.lookup_line(sp.hi())
     }
 
+    #[instrument(skip(self), level = "trace")]
     pub fn is_valid_span(&self, sp: Span) -> Result<(Loc, Loc), SpanLinesError> {
         let lo = self.lookup_char_pos(sp.lo());
-        debug!("span_to_lines: lo={:?}", lo);
+        trace!(?lo);
         let hi = self.lookup_char_pos(sp.hi());
-        debug!("span_to_lines: hi={:?}", hi);
+        trace!(?hi);
         if lo.file.start_pos != hi.file.start_pos {
             return Err(SpanLinesError::DistinctSources(DistinctSources {
                 begin: (lo.file.name.clone(), lo.file.start_pos),

compiler/rustc_target/src/spec/aarch64_apple_darwin.rs

@@ -4,7 +4,9 @@ pub fn target() -> Target {
     let mut base = super::apple_base::opts("macos");
     base.cpu = "apple-a12".to_string();
     base.max_atomic_width = Some(128);
-    base.supported_sanitizers = SanitizerSet::ADDRESS | SanitizerSet::LEAK | SanitizerSet::THREAD;
+
+    // FIXME: The leak sanitizer currently fails the tests, see #88132.
+    base.supported_sanitizers = SanitizerSet::ADDRESS | SanitizerSet::THREAD;
 
     base.pre_link_args.insert(LinkerFlavor::Gcc, vec!["-arch".to_string(), "arm64".to_string()]);
     base.link_env_remove.extend(super::apple_base::macos_link_env_remove());

library/alloc/src/boxed.rs

@@ -1086,6 +1086,7 @@ unsafe impl<#[may_dangle] T: ?Sized, A: Allocator> Drop for Box<T, A> {
     }
 }
 
+#[cfg(not(no_global_oom_handling))]
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: Default> Default for Box<T> {
     /// Creates a `Box<T>`, with the `Default` value for T.
@@ -1394,6 +1395,7 @@ impl<A: Allocator> From<Box<str, A>> for Box<[u8], A> {
     }
 }
 
+#[cfg(not(no_global_oom_handling))]
 #[stable(feature = "box_from_array", since = "1.45.0")]
 impl<T, const N: usize> From<[T; N]> for Box<[T]> {
     /// Converts a `[T; N]` into a `Box<[T]>`

library/alloc/src/vec/mod.rs

@@ -2841,6 +2841,7 @@ impl<T: Clone> From<&mut [T]> for Vec<T> {
     }
 }
 
+#[cfg(not(no_global_oom_handling))]
 #[stable(feature = "vec_from_array", since = "1.44.0")]
 impl<T, const N: usize> From<[T; N]> for Vec<T> {
     #[cfg(not(test))]

src/doc/rustdoc/src/unstable-features.md

@@ -209,6 +209,22 @@ some consideration for their stability, and names that end in a number). Giving
 `rustdoc` will disable this sorting and instead make it print the items in the order they appear in
 the source.
 
+### `--show-type-layout`: add a section to each type's docs describing its memory layout
+
+Using this flag looks like this:
+
+```bash
+$ rustdoc src/lib.rs -Z unstable-options --show-type-layout
+```
+
+When this flag is passed, rustdoc will add a "Layout" section at the bottom of
+each type's docs page that includes a summary of the type's memory layout as
+computed by rustc. For example, rustdoc will show the size in bytes that a value
+of that type will take in memory.
+
+Note that most layout information is **completely unstable** and may even differ
+between compilations.
+
 ### `--resource-suffix`: modifying the name of CSS/JavaScript in crate docs
 
 Using this flag looks like this:
@@ -333,7 +349,7 @@ Some methodology notes about what rustdoc counts in this metric:
 Public items that are not documented can be seen with the built-in `missing_docs` lint. Private
 items that are not documented can be seen with Clippy's `missing_docs_in_private_items` lint.
 
-## `-w`/`--output-format`: output format
+### `-w`/`--output-format`: output format
 
 When using
 [`--show-coverage`](https://doc.rust-lang.org/nightly/rustdoc/unstable-features.html#--show-coverage-get-statistics-about-code-documentation-coverage),

src/librustdoc/html/render/print_item.rs

@@ -1663,7 +1663,7 @@ fn document_type_layout(w: &mut Buffer, cx: &Context<'_>, ty_def_id: DefId) {
             writeln!(
                 w,
                 "<div class=\"warning\"><p><strong>Note:</strong> Most layout information is \
-                 completely unstable and may be different between compiler versions and platforms. \
+                 <strong>completely unstable</strong> and may even differ between compilations. \
                  The only exception is types with certain <code>repr(...)</code> attributes. \
                  Please see the Rust Reference’s \
                  <a href=\"https://doc.rust-lang.org/reference/type-layout.html\">“Type Layout”</a> \

src/test/debuginfo/mutex.rs

@@ -3,8 +3,6 @@
 // cdb-only
 // min-cdb-version: 10.0.21287.1005
 // compile-flags:-g
-// FIXME: Failed on update to 10.0.22000.1
-// ignore-windows
 
 // === CDB TESTS ==================================================================================
 //
@@ -14,17 +12,17 @@
 // cdb-check:m,d              [Type: std::sync::mutex::Mutex<i32>]
 // cdb-check:    [...] inner            [Type: std::sys_common::mutex::MovableMutex]
 // cdb-check:    [...] poison           [Type: std::sync::poison::Flag]
-// cdb-check:    [...] data             [Type: core::cell::UnsafeCell<i32>]
+// cdb-check:    [...] data             : 0 [Type: core::cell::UnsafeCell<i32>]
 
 //
 // cdb-command:dx m.data,d
-// cdb-check:m.data,d         [Type: core::cell::UnsafeCell<i32>]
-// cdb-check:    [...] value            : 0 [Type: int]
+// cdb-check:m.data,d         : 0 [Type: core::cell::UnsafeCell<i32>]
+// cdb-check:    [<Raw View>]     [Type: core::cell::UnsafeCell<i32>]
 
 //
 // cdb-command:dx lock,d
-// cdb-check:lock,d           : Ok [Type: enum$<core::result::Result<std::sync::mutex::MutexGuard<i32>, enum$<std::sync::poison::TryLockError<std::sync::mutex::MutexGuard<i32> >, 0, 1, Poisoned> > >]
-// cdb-check:    [...] variant$         : Ok (0) [Type: core::result::Result]
+// cdb-check:lock,d           : Ok [Type: enum$<core::result::Result<std::sync::mutex::MutexGuard<i32>,enum$<std::sync::poison::TryLockError<std::sync::mutex::MutexGuard<i32> >, 0, 1, Poisoned> > >]
+// cdb-check:    [variant]        : Ok
 // cdb-check:    [...] __0              [Type: std::sync::mutex::MutexGuard<i32>]
 
 use std::sync::Mutex;

src/test/ui/lint/issue-79546-fuel-ice.rs

@@ -0,0 +1,8 @@
+// Regression test for the ICE described in #79546.
+
+// compile-flags: --cap-lints=allow -Zfuel=issue79546=0
+// check-pass
+#![crate_name="issue79546"]
+
+struct S;
+fn main() {}