Rollup of 7 pull requests

compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -795,7 +795,6 @@ impl<'tcx> RegionInferenceContext<'tcx> {
 
         // If the member region lives in a higher universe, we currently choose
         // the most conservative option by leaving it unchanged.
-
         if !self.constraint_sccs().annotation(scc).min_universe().is_root() {
             return;
         }
@@ -823,12 +822,14 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         }
         debug!(?choice_regions, "after ub");
 
-        // At this point we can pick any member of `choice_regions`, but to avoid potential
-        // non-determinism we will pick the *unique minimum* choice.
+        // At this point we can pick any member of `choice_regions` and would like to choose
+        // it to be a small as possible. To avoid potential non-determinism we will pick the
+        // smallest such choice.
         //
         // Because universal regions are only partially ordered (i.e, not every two regions are
         // comparable), we will ignore any region that doesn't compare to all others when picking
         // the minimum choice.
+        //
         // For example, consider `choice_regions = ['static, 'a, 'b, 'c, 'd, 'e]`, where
         // `'static: 'a, 'static: 'b, 'a: 'c, 'b: 'c, 'c: 'd, 'c: 'e`.
         // `['d, 'e]` are ignored because they do not compare - the same goes for `['a, 'b]`.
@@ -853,6 +854,8 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             return;
         };
 
+        // As we require `'scc: 'min_choice`, we have definitely already computed
+        // its `scc_values` at this point.
         let min_choice_scc = self.constraint_sccs.scc(min_choice);
         debug!(?min_choice, ?min_choice_scc);
         if self.scc_values.add_region(scc, min_choice_scc) {

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -15,7 +15,7 @@ use rustc_ast::CRATE_NODE_ID;
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::temp_dir::MaybeTempDir;
-use rustc_errors::{DiagCtxtHandle, FatalError};
+use rustc_errors::DiagCtxtHandle;
 use rustc_fs_util::{fix_windows_verbatim_for_gcc, try_canonicalize};
 use rustc_hir::def_id::{CrateNum, LOCAL_CRATE};
 use rustc_metadata::fs::{METADATA_FILENAME, copy_to_stdout, emit_wrapper_file};
@@ -1039,22 +1039,22 @@ fn link_natively(
         Err(e) => {
             let linker_not_found = e.kind() == io::ErrorKind::NotFound;
 
-            if linker_not_found {
-                sess.dcx().emit_err(errors::LinkerNotFound { linker_path, error: e });
+            let err = if linker_not_found {
+                sess.dcx().emit_err(errors::LinkerNotFound { linker_path, error: e })
             } else {
                 sess.dcx().emit_err(errors::UnableToExeLinker {
                     linker_path,
                     error: e,
                     command_formatted: format!("{cmd:?}"),
-                });
-            }
+                })
+            };
 
             if sess.target.is_like_msvc && linker_not_found {
                 sess.dcx().emit_note(errors::MsvcMissingLinker);
                 sess.dcx().emit_note(errors::CheckInstalledVisualStudio);
                 sess.dcx().emit_note(errors::InsufficientVSCodeProduct);
             }
-            FatalError.raise();
+            err.raise_fatal();
         }
     }
 

compiler/rustc_driver_impl/src/pretty.rs

@@ -4,7 +4,6 @@ use std::cell::Cell;
 use std::fmt::Write;
 
 use rustc_ast_pretty::pprust as pprust_ast;
-use rustc_errors::FatalError;
 use rustc_middle::bug;
 use rustc_middle::mir::{write_mir_graphviz, write_mir_pretty};
 use rustc_middle::ty::{self, TyCtxt};
@@ -311,9 +310,7 @@ pub fn print<'tcx>(sess: &Session, ppm: PpMode, ex: PrintExtra<'tcx>) {
             let tcx = ex.tcx();
             let mut out = String::new();
             rustc_hir_analysis::check_crate(tcx);
-            if tcx.dcx().has_errors().is_some() {
-                FatalError.raise();
-            }
+            tcx.dcx().abort_if_errors();
             debug!("pretty printing THIR tree");
             for did in tcx.hir().body_owners() {
                 let _ = writeln!(out, "{:?}:\n{}\n", did, tcx.thir_tree(did));
@@ -324,9 +321,7 @@ pub fn print<'tcx>(sess: &Session, ppm: PpMode, ex: PrintExtra<'tcx>) {
             let tcx = ex.tcx();
             let mut out = String::new();
             rustc_hir_analysis::check_crate(tcx);
-            if tcx.dcx().has_errors().is_some() {
-                FatalError.raise();
-            }
+            tcx.dcx().abort_if_errors();
             debug!("pretty printing THIR flat");
             for did in tcx.hir().body_owners() {
                 let _ = writeln!(out, "{:?}:\n{}\n", did, tcx.thir_flat(did));

compiler/rustc_hir_typeck/src/method/probe.rs

@@ -1329,6 +1329,15 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
         mutbl: hir::Mutability,
         track_unstable_candidates: bool,
     ) -> Result<(), MethodError<'tcx>> {
+        // The errors emitted by this function are part of
+        // the arbitrary self types work, and should not impact
+        // other users.
+        if !self.tcx.features().arbitrary_self_types()
+            && !self.tcx.features().arbitrary_self_types_pointers()
+        {
+            return Ok(());
+        }
+
         // We don't want to remember any of the diagnostic hints from this
         // shadow search, but we do need to provide Some/None for the
         // unstable_candidates in order to reflect the behavior of the

compiler/rustc_mir_transform/src/coverage/mappings.rs

@@ -80,7 +80,7 @@ pub(super) fn extract_all_mapping_info_from_mir<'tcx>(
     tcx: TyCtxt<'tcx>,
     mir_body: &mir::Body<'tcx>,
     hir_info: &ExtractedHirInfo,
-    basic_coverage_blocks: &CoverageGraph,
+    graph: &CoverageGraph,
 ) -> ExtractedMappings {
     let mut code_mappings = vec![];
     let mut branch_pairs = vec![];
@@ -102,23 +102,23 @@ pub(super) fn extract_all_mapping_info_from_mir<'tcx>(
         }
     } else {
         // Extract coverage spans from MIR statements/terminators as normal.
-        extract_refined_covspans(mir_body, hir_info, basic_coverage_blocks, &mut code_mappings);
+        extract_refined_covspans(mir_body, hir_info, graph, &mut code_mappings);
     }
 
-    branch_pairs.extend(extract_branch_pairs(mir_body, hir_info, basic_coverage_blocks));
+    branch_pairs.extend(extract_branch_pairs(mir_body, hir_info, graph));
 
     extract_mcdc_mappings(
         mir_body,
         tcx,
         hir_info.body_span,
-        basic_coverage_blocks,
+        graph,
         &mut mcdc_bitmap_bits,
         &mut mcdc_degraded_branches,
         &mut mcdc_mappings,
     );
 
     ExtractedMappings {
-        num_bcbs: basic_coverage_blocks.num_nodes(),
+        num_bcbs: graph.num_nodes(),
         code_mappings,
         branch_pairs,
         mcdc_bitmap_bits,
@@ -211,7 +211,7 @@ fn resolve_block_markers(
 pub(super) fn extract_branch_pairs(
     mir_body: &mir::Body<'_>,
     hir_info: &ExtractedHirInfo,
-    basic_coverage_blocks: &CoverageGraph,
+    graph: &CoverageGraph,
 ) -> Vec<BranchPair> {
     let Some(coverage_info_hi) = mir_body.coverage_info_hi.as_deref() else { return vec![] };
 
@@ -228,8 +228,7 @@ pub(super) fn extract_branch_pairs(
             }
             let span = unexpand_into_body_span(raw_span, hir_info.body_span)?;
 
-            let bcb_from_marker =
-                |marker: BlockMarkerId| basic_coverage_blocks.bcb_from_bb(block_markers[marker]?);
+            let bcb_from_marker = |marker: BlockMarkerId| graph.bcb_from_bb(block_markers[marker]?);
 
             let true_bcb = bcb_from_marker(true_marker)?;
             let false_bcb = bcb_from_marker(false_marker)?;
@@ -243,7 +242,7 @@ pub(super) fn extract_mcdc_mappings(
     mir_body: &mir::Body<'_>,
     tcx: TyCtxt<'_>,
     body_span: Span,
-    basic_coverage_blocks: &CoverageGraph,
+    graph: &CoverageGraph,
     mcdc_bitmap_bits: &mut usize,
     mcdc_degraded_branches: &mut impl Extend<MCDCBranch>,
     mcdc_mappings: &mut impl Extend<(MCDCDecision, Vec<MCDCBranch>)>,
@@ -252,8 +251,7 @@ pub(super) fn extract_mcdc_mappings(
 
     let block_markers = resolve_block_markers(coverage_info_hi, mir_body);
 
-    let bcb_from_marker =
-        |marker: BlockMarkerId| basic_coverage_blocks.bcb_from_bb(block_markers[marker]?);
+    let bcb_from_marker = |marker: BlockMarkerId| graph.bcb_from_bb(block_markers[marker]?);
 
     let check_branch_bcb =
         |raw_span: Span, true_marker: BlockMarkerId, false_marker: BlockMarkerId| {

compiler/rustc_mir_transform/src/coverage/mod.rs

@@ -71,16 +71,15 @@ fn instrument_function_for_coverage<'tcx>(tcx: TyCtxt<'tcx>, mir_body: &mut mir:
     let _span = debug_span!("instrument_function_for_coverage", ?def_id).entered();
 
     let hir_info = extract_hir_info(tcx, def_id.expect_local());
-    let basic_coverage_blocks = CoverageGraph::from_mir(mir_body);
+
+    // Build the coverage graph, which is a simplified view of the MIR control-flow
+    // graph that ignores some details not relevant to coverage instrumentation.
+    let graph = CoverageGraph::from_mir(mir_body);
 
     ////////////////////////////////////////////////////
     // Extract coverage spans and other mapping info from MIR.
-    let extracted_mappings = mappings::extract_all_mapping_info_from_mir(
-        tcx,
-        mir_body,
-        &hir_info,
-        &basic_coverage_blocks,
-    );
+    let extracted_mappings =
+        mappings::extract_all_mapping_info_from_mir(tcx, mir_body, &hir_info, &graph);
 
     ////////////////////////////////////////////////////
     // Create an optimized mix of `Counter`s and `Expression`s for the `CoverageGraph`. Ensure
@@ -94,7 +93,7 @@ fn instrument_function_for_coverage<'tcx>(tcx: TyCtxt<'tcx>, mir_body: &mut mir:
     }
 
     let coverage_counters =
-        CoverageCounters::make_bcb_counters(&basic_coverage_blocks, &bcbs_with_counter_mappings);
+        CoverageCounters::make_bcb_counters(&graph, &bcbs_with_counter_mappings);
 
     let mappings = create_mappings(&extracted_mappings, &coverage_counters);
     if mappings.is_empty() {
@@ -103,14 +102,9 @@ fn instrument_function_for_coverage<'tcx>(tcx: TyCtxt<'tcx>, mir_body: &mut mir:
         return;
     }
 
-    inject_coverage_statements(
-        mir_body,
-        &basic_coverage_blocks,
-        &extracted_mappings,
-        &coverage_counters,
-    );
+    inject_coverage_statements(mir_body, &graph, &extracted_mappings, &coverage_counters);
 
-    inject_mcdc_statements(mir_body, &basic_coverage_blocks, &extracted_mappings);
+    inject_mcdc_statements(mir_body, &graph, &extracted_mappings);
 
     let mcdc_num_condition_bitmaps = extracted_mappings
         .mcdc_mappings
@@ -243,7 +237,7 @@ fn create_mappings(
 /// inject any necessary coverage statements into MIR.
 fn inject_coverage_statements<'tcx>(
     mir_body: &mut mir::Body<'tcx>,
-    basic_coverage_blocks: &CoverageGraph,
+    graph: &CoverageGraph,
     extracted_mappings: &ExtractedMappings,
     coverage_counters: &CoverageCounters,
 ) {
@@ -253,12 +247,12 @@ fn inject_coverage_statements<'tcx>(
         // For BCB nodes this is just their first block, but for edges we need
         // to create a new block between the two BCBs, and inject into that.
         let target_bb = match site {
-            Site::Node { bcb } => basic_coverage_blocks[bcb].leader_bb(),
+            Site::Node { bcb } => graph[bcb].leader_bb(),
             Site::Edge { from_bcb, to_bcb } => {
                 // Create a new block between the last block of `from_bcb` and
                 // the first block of `to_bcb`.
-                let from_bb = basic_coverage_blocks[from_bcb].last_bb();
-                let to_bb = basic_coverage_blocks[to_bcb].leader_bb();
+                let from_bb = graph[from_bcb].last_bb();
+                let to_bb = graph[to_bcb].leader_bb();
 
                 let new_bb = inject_edge_counter_basic_block(mir_body, from_bb, to_bb);
                 debug!(
@@ -291,7 +285,7 @@ fn inject_coverage_statements<'tcx>(
         inject_statement(
             mir_body,
             CoverageKind::ExpressionUsed { id: expression_id },
-            basic_coverage_blocks[bcb].leader_bb(),
+            graph[bcb].leader_bb(),
         );
     }
 }
@@ -300,13 +294,13 @@ fn inject_coverage_statements<'tcx>(
 /// For each decision inject statements to update test vector bitmap after it has been evaluated.
 fn inject_mcdc_statements<'tcx>(
     mir_body: &mut mir::Body<'tcx>,
-    basic_coverage_blocks: &CoverageGraph,
+    graph: &CoverageGraph,
     extracted_mappings: &ExtractedMappings,
 ) {
     for (decision, conditions) in &extracted_mappings.mcdc_mappings {
         // Inject test vector update first because `inject_statement` always insert new statement at head.
         for &end in &decision.end_bcbs {
-            let end_bb = basic_coverage_blocks[end].leader_bb();
+            let end_bb = graph[end].leader_bb();
             inject_statement(
                 mir_body,
                 CoverageKind::TestVectorBitmapUpdate {
@@ -327,7 +321,7 @@ fn inject_mcdc_statements<'tcx>(
         } in conditions
         {
             for (index, bcb) in [(false_index, false_bcb), (true_index, true_bcb)] {
-                let bb = basic_coverage_blocks[bcb].leader_bb();
+                let bb = graph[bcb].leader_bb();
                 inject_statement(
                     mir_body,
                     CoverageKind::CondBitmapUpdate {

compiler/rustc_mir_transform/src/coverage/spans.rs

@@ -17,14 +17,13 @@ mod from_mir;
 pub(super) fn extract_refined_covspans(
     mir_body: &mir::Body<'_>,
     hir_info: &ExtractedHirInfo,
-    basic_coverage_blocks: &CoverageGraph,
+    graph: &CoverageGraph,
     code_mappings: &mut impl Extend<mappings::CodeMapping>,
 ) {
-    let ExtractedCovspans { mut covspans } =
-        extract_covspans_from_mir(mir_body, hir_info, basic_coverage_blocks);
+    let ExtractedCovspans { mut covspans } = extract_covspans_from_mir(mir_body, hir_info, graph);
 
     // First, perform the passes that need macro information.
-    covspans.sort_by(|a, b| basic_coverage_blocks.cmp_in_dominator_order(a.bcb, b.bcb));
+    covspans.sort_by(|a, b| graph.cmp_in_dominator_order(a.bcb, b.bcb));
     remove_unwanted_expansion_spans(&mut covspans);
     split_visible_macro_spans(&mut covspans);
 
@@ -34,7 +33,7 @@ pub(super) fn extract_refined_covspans(
     let compare_covspans = |a: &Covspan, b: &Covspan| {
         compare_spans(a.span, b.span)
             // After deduplication, we want to keep only the most-dominated BCB.
-            .then_with(|| basic_coverage_blocks.cmp_in_dominator_order(a.bcb, b.bcb).reverse())
+            .then_with(|| graph.cmp_in_dominator_order(a.bcb, b.bcb).reverse())
     };
     covspans.sort_by(compare_covspans);
 

compiler/rustc_mir_transform/src/coverage/spans/from_mir.rs

@@ -22,13 +22,13 @@ pub(crate) struct ExtractedCovspans {
 pub(crate) fn extract_covspans_from_mir(
     mir_body: &mir::Body<'_>,
     hir_info: &ExtractedHirInfo,
-    basic_coverage_blocks: &CoverageGraph,
+    graph: &CoverageGraph,
 ) -> ExtractedCovspans {
     let &ExtractedHirInfo { body_span, .. } = hir_info;
 
     let mut covspans = vec![];
 
-    for (bcb, bcb_data) in basic_coverage_blocks.iter_enumerated() {
+    for (bcb, bcb_data) in graph.iter_enumerated() {
         bcb_to_initial_coverage_spans(mir_body, body_span, bcb, bcb_data, &mut covspans);
     }