Auto merge of #154503 - RalfJung:rollup-DkU2JXL, r=RalfJung

Rollup of 11 pull requests

Successful merges:

 - #152880 (Tweak incorrect assoc item note)
 - #153526 (Fix LegacyKeyValueFormat report from docker build: i686)
 - #153613 (interpreter error reporting: remove arguments that are always the same)
 - #154029 (Replace `truncate(0)` with `clear()`)
 - #154125 (Inline and remove `DepGraphData::try_mark_parent_green`.)
 - #154185 (Prevent no_threads RwLock's write() impl from setting mode to -1 when it is locked for reading)
 - #154394 (Normalize rustc path prefix when testing `-Z track-diagnostics`)
 - #154450 (Use the normal arg-parsing machinery for `-Zassert-incr-state`)
 - #154475 (Emit a pre-expansion feature gate warning for `box`'ed struct field patterns)
 - #154500 (EnumSizeOpt: use Allocation::write_scalar instead of manual endianess logic)
 - #154502 (interpret: ensure that untupled arguments are actually tuples)

Author: bors

compiler/rustc_const_eval/src/const_eval/error.rs

@@ -1,14 +1,14 @@
 use std::{fmt, mem};
 
-use rustc_errors::Diag;
+use rustc_errors::{Diag, E0080};
 use rustc_middle::mir::AssertKind;
 use rustc_middle::mir::interpret::{
     AllocId, Provenance, ReportedErrorInfo, UndefinedBehaviorInfo, UnsupportedOpInfo,
 };
 use rustc_middle::query::TyCtxtAt;
 use rustc_middle::ty::ConstInt;
 use rustc_middle::ty::layout::LayoutError;
-use rustc_span::{Span, Symbol};
+use rustc_span::{DUMMY_SP, Span, Symbol};
 
 use super::CompileTimeMachine;
 use crate::errors::{self, FrameNote};
@@ -164,36 +164,30 @@ pub fn get_span_and_frames<'tcx>(
 /// This will use the `mk` function for adding more information to the error.
 /// You can use it to add a stacktrace of current execution according to
 /// `get_span_and_frames` or just give context on where the const eval error happened.
-pub(super) fn report<'tcx, C, F>(
+pub(super) fn report<'tcx>(
     ecx: &InterpCx<'tcx, CompileTimeMachine<'tcx>>,
     error: InterpErrorKind<'tcx>,
-    span: Span,
-    get_span_and_frames: C,
-    mk: F,
-) -> ErrorHandled
-where
-    C: FnOnce() -> (Span, Vec<FrameNote>),
-    F: FnOnce(&mut Diag<'_>, Span, Vec<FrameNote>),
-{
+    mk: impl FnOnce(&mut Diag<'_>, Span, Vec<FrameNote>),
+) -> ErrorHandled {
     let tcx = ecx.tcx.tcx;
     // Special handling for certain errors
     match error {
         // Don't emit a new diagnostic for these errors, they are already reported elsewhere or
         // should remain silent.
-        err_inval!(AlreadyReported(info)) => ErrorHandled::Reported(info, span),
+        err_inval!(AlreadyReported(info)) => ErrorHandled::Reported(info, DUMMY_SP),
         err_inval!(Layout(LayoutError::TooGeneric(_))) | err_inval!(TooGeneric) => {
-            ErrorHandled::TooGeneric(span)
+            ErrorHandled::TooGeneric(DUMMY_SP)
         }
         err_inval!(Layout(LayoutError::ReferencesError(guar))) => {
             // This can occur in infallible promoteds e.g. when a non-existent type or field is
             // encountered.
-            ErrorHandled::Reported(ReportedErrorInfo::allowed_in_infallible(guar), span)
+            ErrorHandled::Reported(ReportedErrorInfo::allowed_in_infallible(guar), DUMMY_SP)
         }
         // Report remaining errors.
         _ => {
-            let (our_span, frames) = get_span_and_frames();
-            let span = span.substitute_dummy(our_span);
-            let mut err = tcx.dcx().struct_span_err(our_span, error.to_string());
+            let (span, frames) = super::get_span_and_frames(ecx.tcx, ecx.stack());
+            let mut err = tcx.dcx().struct_span_err(span, error.to_string());
+            err.code(E0080);
             if matches!(
                 error,
                 InterpErrorKind::UndefinedBehavior(UndefinedBehaviorInfo::ValidationError {

compiler/rustc_const_eval/src/const_eval/eval_queries.rs

@@ -2,7 +2,6 @@ use std::sync::atomic::Ordering::Relaxed;
 
 use either::{Left, Right};
 use rustc_abi::{self as abi, BackendRepr};
-use rustc_errors::{E0080, msg};
 use rustc_hir::def::DefKind;
 use rustc_middle::mir::interpret::{AllocId, ErrorHandled, InterpErrorInfo, ReportedErrorInfo};
 use rustc_middle::mir::{self, ConstAlloc, ConstValue};
@@ -11,8 +10,8 @@ use rustc_middle::ty::layout::{HasTypingEnv, TyAndLayout};
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_middle::{bug, throw_inval};
+use rustc_span::Span;
 use rustc_span::def_id::LocalDefId;
-use rustc_span::{DUMMY_SP, Span};
 use tracing::{debug, instrument, trace};
 
 use super::{CanAccessMutGlobal, CompileTimeInterpCx, CompileTimeMachine};
@@ -458,32 +457,20 @@ fn report_eval_error<'tcx>(
     let (error, backtrace) = error.into_parts();
     backtrace.print_backtrace();
 
-    super::report(
-        ecx,
-        error,
-        DUMMY_SP,
-        || super::get_span_and_frames(ecx.tcx, ecx.stack()),
-        |diag, span, frames| {
-            let num_frames = frames.len();
-            // FIXME(oli-obk): figure out how to use structured diagnostics again.
-            diag.code(E0080);
-            diag.span_label(
-                span,
-                msg!(
-                    "evaluation of `{$instance}` failed {$num_frames ->
-                        [0] here
-                        *[other] inside this call
-                    }"
-                ),
-            );
-            for frame in frames {
-                diag.subdiagnostic(frame);
-            }
-            // Add after the frame rendering above, as it adds its own `instance` args.
-            diag.arg("instance", with_no_trimmed_paths!(cid.instance.to_string()));
-            diag.arg("num_frames", num_frames);
-        },
-    )
+    super::report(ecx, error, |diag, span, frames| {
+        let num_frames = frames.len();
+        diag.span_label(
+            span,
+            format!(
+                "evaluation of `{instance}` failed {where_}",
+                instance = with_no_trimmed_paths!(cid.instance.to_string()),
+                where_ = if num_frames == 0 { "here" } else { "inside this call" },
+            ),
+        );
+        for frame in frames {
+            diag.subdiagnostic(frame);
+        }
+    })
 }
 
 #[inline(never)]
@@ -506,20 +493,10 @@ fn report_validation_error<'tcx>(
     let raw_bytes =
         errors::RawBytesNote { size: info.size.bytes(), align: info.align.bytes(), bytes };
 
-    crate::const_eval::report(
-        ecx,
-        error,
-        DUMMY_SP,
-        || crate::const_eval::get_span_and_frames(ecx.tcx, ecx.stack()),
-        move |diag, span, frames| {
-            // FIXME(oli-obk): figure out how to use structured diagnostics again.
-            diag.code(E0080);
-            diag.span_label(span, "it is undefined behavior to use this value");
-            diag.note("the rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rustc repository if you believe it should not be considered undefined behavior.");
-            for frame in frames {
-                diag.subdiagnostic(frame);
-            }
-            diag.subdiagnostic(raw_bytes);
-        },
-    )
+    crate::const_eval::report(ecx, error, move |diag, span, frames| {
+        diag.span_label(span, "it is undefined behavior to use this value");
+        diag.note("the rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rustc repository if you believe it should not be considered undefined behavior.");
+        assert!(frames.is_empty()); // we just report validation errors for the final const here
+        diag.subdiagnostic(raw_bytes);
+    })
 }

compiler/rustc_const_eval/src/interpret/call.rs

@@ -60,7 +60,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
     }
 
     /// Helper function for argument untupling.
-    pub(super) fn fn_arg_field(
+    fn fn_arg_project_field(
         &self,
         arg: &FnArg<'tcx, M::Provenance>,
         field: FieldIdx,
@@ -655,12 +655,17 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
                     if caller_abi == ExternAbi::RustCall && !args.is_empty() {
                         // Untuple
                         let (untuple_arg, args) = args.split_last().unwrap();
+                        let ty::Tuple(untuple_fields) = untuple_arg.layout().ty.kind() else {
+                            span_bug!(self.cur_span(), "untuple argument must be a tuple")
+                        };
                         trace!("init_fn_call: Will pass last argument by untupling");
                         Cow::from(
                             args.iter()
+                                // The regular arguments.
                                 .map(|a| interp_ok(a.clone()))
-                                .chain((0..untuple_arg.layout().fields.count()).map(|i| {
-                                    self.fn_arg_field(untuple_arg, FieldIdx::from_usize(i))
+                                // The fields of the untupled argument.
+                                .chain((0..untuple_fields.len()).map(|i| {
+                                    self.fn_arg_project_field(untuple_arg, FieldIdx::from_usize(i))
                                 }))
                                 .collect::<InterpResult<'_, Vec<_>>>()?,
                         )

compiler/rustc_data_structures/src/obligation_forest/mod.rs

@@ -702,7 +702,7 @@ impl<O: ForestObligation> ObligationForest<O> {
             self.apply_rewrites(&node_rewrites);
         }
 
-        node_rewrites.truncate(0);
+        node_rewrites.clear();
         self.reused_node_vec = node_rewrites;
     }
 

compiler/rustc_hir_typeck/src/method/suggest.rs

@@ -1177,15 +1177,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let is_method = mode == Mode::MethodCall;
         let item_kind = if is_method {
             "method"
-        } else if rcvr_ty.is_enum() {
-            "variant or associated item"
+        } else if rcvr_ty.is_enum() || rcvr_ty.is_fresh_ty() {
+            "variant, associated function, or constant"
         } else {
-            match (item_ident.as_str().chars().next(), rcvr_ty.is_fresh_ty()) {
-                (Some(name), false) if name.is_lowercase() => "function or associated item",
-                (Some(_), false) => "associated item",
-                (Some(_), true) | (None, false) => "variant or associated item",
-                (None, true) => "variant",
-            }
+            "associated function or constant"
         };
 
         if let Err(guar) = self.report_failed_method_call_on_numerical_infer_var(

compiler/rustc_incremental/src/persist/load.rs

@@ -38,19 +38,8 @@ pub enum LoadResult<T> {
 impl<T: Default> LoadResult<T> {
     /// Accesses the data returned in [`LoadResult::Ok`].
     pub fn open(self, sess: &Session) -> T {
-        // Check for errors when using `-Zassert-incremental-state`
-        match (sess.opts.assert_incr_state, &self) {
-            (Some(IncrementalStateAssertion::NotLoaded), LoadResult::Ok { .. }) => {
-                sess.dcx().emit_fatal(errors::AssertNotLoaded);
-            }
-            (
-                Some(IncrementalStateAssertion::Loaded),
-                LoadResult::LoadDepGraph(..) | LoadResult::DataOutOfDate,
-            ) => {
-                sess.dcx().emit_fatal(errors::AssertLoaded);
-            }
-            _ => {}
-        };
+        // Emit a fatal error if `-Zassert-incr-state` is present and unsatisfied.
+        maybe_assert_incr_state(sess, &self);
 
         match self {
             LoadResult::LoadDepGraph(path, err) => {
@@ -188,6 +177,32 @@ pub fn load_query_result_cache(sess: &Session) -> Option<OnDiskCache> {
     }
 }
 
+/// Emits a fatal error if the assertion in `-Zassert-incr-state` doesn't match
+/// the outcome of trying to load previous-session state.
+fn maybe_assert_incr_state(sess: &Session, load_result: &LoadResult<impl Sized>) {
+    // Return immediately if there's nothing to assert.
+    let Some(assertion) = sess.opts.unstable_opts.assert_incr_state else { return };
+
+    // Match exhaustively to make sure we don't miss any cases.
+    let loaded = match load_result {
+        LoadResult::Ok { .. } => true,
+        LoadResult::DataOutOfDate | LoadResult::LoadDepGraph(..) => false,
+    };
+
+    match assertion {
+        IncrementalStateAssertion::Loaded => {
+            if !loaded {
+                sess.dcx().emit_fatal(errors::AssertLoaded);
+            }
+        }
+        IncrementalStateAssertion::NotLoaded => {
+            if loaded {
+                sess.dcx().emit_fatal(errors::AssertNotLoaded)
+            }
+        }
+    }
+}
+
 /// Setups the dependency graph by loading an existing graph from disk and set up streaming of a
 /// new graph to an incremental session directory.
 pub fn setup_dep_graph(

compiler/rustc_interface/src/tests.rs

@@ -12,12 +12,12 @@ use rustc_hir::attrs::{CollapseMacroDebuginfo, NativeLibKind};
 use rustc_session::config::{
     AnnotateMoves, AutoDiff, BranchProtection, CFGuard, Cfg, CoverageLevel, CoverageOptions,
     DebugInfo, DumpMonoStatsFormat, ErrorOutputType, ExternEntry, ExternLocation, Externs,
-    FmtDebug, FunctionReturn, InliningThreshold, Input, InstrumentCoverage, InstrumentXRay,
-    LinkSelfContained, LinkerPluginLto, LocationDetail, LtoCli, MirIncludeSpans, NextSolverConfig,
-    Offload, Options, OutFileName, OutputType, OutputTypes, PAuthKey, PacRet, Passes,
-    PatchableFunctionEntry, Polonius, ProcMacroExecutionStrategy, Strip, SwitchWithOptPath,
-    SymbolManglingVersion, WasiExecModel, build_configuration, build_session_options,
-    rustc_optgroups,
+    FmtDebug, FunctionReturn, IncrementalStateAssertion, InliningThreshold, Input,
+    InstrumentCoverage, InstrumentXRay, LinkSelfContained, LinkerPluginLto, LocationDetail, LtoCli,
+    MirIncludeSpans, NextSolverConfig, Offload, Options, OutFileName, OutputType, OutputTypes,
+    PAuthKey, PacRet, Passes, PatchableFunctionEntry, Polonius, ProcMacroExecutionStrategy, Strip,
+    SwitchWithOptPath, SymbolManglingVersion, WasiExecModel, build_configuration,
+    build_session_options, rustc_optgroups,
 };
 use rustc_session::lint::Level;
 use rustc_session::search_paths::SearchPath;
@@ -686,7 +686,7 @@ fn test_unstable_options_tracking_hash() {
 
     // Make sure that changing an [UNTRACKED] option leaves the hash unchanged.
     // tidy-alphabetical-start
-    untracked!(assert_incr_state, Some(String::from("loaded")));
+    untracked!(assert_incr_state, Some(IncrementalStateAssertion::Loaded));
     untracked!(codegen_source_order, true);
     untracked!(deduplicate_diagnostics, false);
     untracked!(dump_dep_graph, true);