1#![allow(rustc::diagnostic_outside_of_impl)]
3#![allow(rustc::untranslatable_diagnostic)]
4#![feature(array_windows)]
5#![feature(assert_matches)]
6#![feature(box_patterns)]
7#![feature(if_let_guard)]
8#![feature(iter_intersperse)]
9#![feature(never_type)]
10#![feature(try_blocks)]
11mod _match;
14mod autoderef;
15mod callee;
16pub mod cast;
18mod check;
19mod closure;
20mod coercion;
21mod demand;
22mod diverges;
23mod errors;
24mod expectation;
25mod expr;
26mod inline_asm;
27pub mod expr_use_visitor;
29mod fallback;
30mod fn_ctxt;
31mod gather_locals;
32mod intrinsicck;
33mod method;
34mod naked_functions;
35mod op;
36mod opaque_types;
37mod pat;
38mod place_op;
39mod rvalue_scopes;
40mod typeck_root_ctxt;
41mod upvar;
42mod writeback;
43
44pub use coercion::can_coerce;
45use fn_ctxt::FnCtxt;
46use rustc_data_structures::unord::UnordSet;
47use rustc_errors::codes::*;
48use rustc_errors::{Applicability, ErrorGuaranteed, pluralize, struct_span_code_err};
49use rustc_hir as hir;
50use rustc_hir::def::{DefKind, Res};
51use rustc_hir::{HirId, HirIdMap, Node};
52use rustc_hir_analysis::check::check_abi;
53use rustc_hir_analysis::hir_ty_lowering::HirTyLowerer;
54use rustc_infer::traits::{ObligationCauseCode, ObligationInspector, WellFormedLoc};
55use rustc_middle::query::Providers;
56use rustc_middle::ty::{self, Ty, TyCtxt};
57use rustc_middle::{bug, span_bug};
58use rustc_session::config;
59use rustc_span::def_id::LocalDefId;
60use rustc_span::{Span, sym};
61use tracing::{debug, instrument};
62use typeck_root_ctxt::TypeckRootCtxt;
63
64use crate::check::check_fn;
65use crate::coercion::DynamicCoerceMany;
66use crate::diverges::Diverges;
67use crate::expectation::Expectation;
68use crate::fn_ctxt::LoweredTy;
69use crate::gather_locals::GatherLocalsVisitor;
70
71rustc_fluent_macro::fluent_messages! { "../messages.ftl" }
72
73#[macro_export]
74macro_rules! type_error_struct {
75 ($dcx:expr, $span:expr, $typ:expr, $code:expr, $($message:tt)*) => ({
76 let mut err = rustc_errors::struct_span_code_err!($dcx, $span, $code, $($message)*);
77
78 if $typ.references_error() {
79 err.downgrade_to_delayed_bug();
80 }
81
82 err
83 })
84}
85
86fn used_trait_imports(tcx: TyCtxt<'_>, def_id: LocalDefId) -> &UnordSet<LocalDefId> {
87 &tcx.typeck(def_id).used_trait_imports
88}
89
90fn typeck<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> &'tcx ty::TypeckResults<'tcx> {
91 typeck_with_inspect(tcx, def_id, None)
92}
93
94pub fn inspect_typeck<'tcx>(
99 tcx: TyCtxt<'tcx>,
100 def_id: LocalDefId,
101 inspect: ObligationInspector<'tcx>,
102) -> &'tcx ty::TypeckResults<'tcx> {
103 typeck_with_inspect(tcx, def_id, Some(inspect))
104}
105
106#[instrument(level = "debug", skip(tcx, inspector), ret)]
107fn typeck_with_inspect<'tcx>(
108 tcx: TyCtxt<'tcx>,
109 def_id: LocalDefId,
110 inspector: Option<ObligationInspector<'tcx>>,
111) -> &'tcx ty::TypeckResults<'tcx> {
112 let typeck_root_def_id = tcx.typeck_root_def_id(def_id.to_def_id()).expect_local();
115 if typeck_root_def_id != def_id {
116 return tcx.typeck(typeck_root_def_id);
117 }
118
119 let id = tcx.local_def_id_to_hir_id(def_id);
120 let node = tcx.hir_node(id);
121 let span = tcx.def_span(def_id);
122
123 let body_id = node.body_id().unwrap_or_else(|| {
125 span_bug!(span, "can't type-check body of {:?}", def_id);
126 });
127 let body = tcx.hir_body(body_id);
128
129 let param_env = tcx.param_env(def_id);
130
131 let root_ctxt = TypeckRootCtxt::new(tcx, def_id);
132 if let Some(inspector) = inspector {
133 root_ctxt.infcx.attach_obligation_inspector(inspector);
134 }
135 let mut fcx = FnCtxt::new(&root_ctxt, param_env, def_id);
136
137 if let hir::Node::Item(hir::Item { kind: hir::ItemKind::GlobalAsm { .. }, .. }) = node {
138 let ty = fcx.check_expr(body.value);
141 fcx.write_ty(id, ty);
142 } else if let Some(hir::FnSig { header, decl, .. }) = node.fn_sig() {
143 let fn_sig = if decl.output.is_suggestable_infer_ty().is_some() {
144 fcx.lowerer().lower_fn_ty(id, header.safety(), header.abi, decl, None, None)
149 } else {
150 tcx.fn_sig(def_id).instantiate_identity()
151 };
152
153 check_abi(tcx, span, fn_sig.abi());
154
155 let mut fn_sig = tcx.liberate_late_bound_regions(def_id.to_def_id(), fn_sig);
157
158 let arg_span =
164 |idx| decl.inputs.get(idx).map_or(decl.output.span(), |arg: &hir::Ty<'_>| arg.span);
165
166 fn_sig.inputs_and_output = tcx.mk_type_list_from_iter(
167 fn_sig
168 .inputs_and_output
169 .iter()
170 .enumerate()
171 .map(|(idx, ty)| fcx.normalize(arg_span(idx), ty)),
172 );
173
174 if tcx.has_attr(def_id, sym::naked) {
175 naked_functions::typeck_naked_fn(tcx, def_id, body);
176 }
177
178 check_fn(&mut fcx, fn_sig, None, decl, def_id, body, tcx.features().unsized_fn_params());
179 } else {
180 let expected_type = if let Some(infer_ty) = infer_type_if_missing(&fcx, node) {
181 infer_ty
182 } else if let Some(ty) = node.ty()
183 && ty.is_suggestable_infer_ty()
184 {
185 fcx.lowerer().lower_ty(ty)
190 } else {
191 tcx.type_of(def_id).instantiate_identity()
192 };
193
194 let expected_type = fcx.normalize(body.value.span, expected_type);
195
196 let wf_code = ObligationCauseCode::WellFormed(Some(WellFormedLoc::Ty(def_id)));
197 fcx.register_wf_obligation(expected_type.into(), body.value.span, wf_code);
198
199 fcx.check_expr_coercible_to_type(body.value, expected_type, None);
200
201 fcx.write_ty(id, expected_type);
202 };
203
204 fcx.check_repeat_exprs();
215
216 fcx.type_inference_fallback();
217
218 fcx.check_casts();
221 fcx.select_obligations_where_possible(|_| {});
222
223 fcx.closure_analyze(body);
226 assert!(fcx.deferred_call_resolutions.borrow().is_empty());
227 fcx.resolve_rvalue_scopes(def_id.to_def_id());
230
231 for (ty, span, code) in fcx.deferred_sized_obligations.borrow_mut().drain(..) {
232 let ty = fcx.normalize(span, ty);
233 fcx.require_type_is_sized(ty, span, code);
234 }
235
236 fcx.select_obligations_where_possible(|_| {});
237
238 debug!(pending_obligations = ?fcx.fulfillment_cx.borrow().pending_obligations());
239
240 fcx.resolve_coroutine_interiors();
242
243 debug!(pending_obligations = ?fcx.fulfillment_cx.borrow().pending_obligations());
244
245 if let None = fcx.infcx.tainted_by_errors() {
246 fcx.report_ambiguity_errors();
247 }
248
249 if let None = fcx.infcx.tainted_by_errors() {
250 fcx.check_transmutes();
251 }
252
253 fcx.check_asms();
254
255 let typeck_results = fcx.resolve_type_vars_in_body(body);
256
257 fcx.detect_opaque_types_added_during_writeback();
258
259 assert_eq!(typeck_results.hir_owner, id.owner);
262
263 typeck_results
264}
265
266fn infer_type_if_missing<'tcx>(fcx: &FnCtxt<'_, 'tcx>, node: Node<'tcx>) -> Option<Ty<'tcx>> {
267 let tcx = fcx.tcx;
268 let def_id = fcx.body_id;
269 let expected_type = if let Some(&hir::Ty { kind: hir::TyKind::Infer(()), span, .. }) = node.ty()
270 {
271 if let Some(item) = tcx.opt_associated_item(def_id.into())
272 && let ty::AssocKind::Const { .. } = item.kind
273 && let ty::AssocItemContainer::Impl = item.container
274 && let Some(trait_item_def_id) = item.trait_item_def_id
275 {
276 let impl_def_id = item.container_id(tcx);
277 let impl_trait_ref = tcx.impl_trait_ref(impl_def_id).unwrap().instantiate_identity();
278 let args = ty::GenericArgs::identity_for_item(tcx, def_id).rebase_onto(
279 tcx,
280 impl_def_id,
281 impl_trait_ref.args,
282 );
283 tcx.check_args_compatible(trait_item_def_id, args)
284 .then(|| tcx.type_of(trait_item_def_id).instantiate(tcx, args))
285 } else {
286 Some(fcx.next_ty_var(span))
287 }
288 } else if let Node::AnonConst(_) = node {
289 let id = tcx.local_def_id_to_hir_id(def_id);
290 match tcx.parent_hir_node(id) {
291 Node::Ty(&hir::Ty { kind: hir::TyKind::Typeof(ref anon_const), span, .. })
292 if anon_const.hir_id == id =>
293 {
294 Some(fcx.next_ty_var(span))
295 }
296 Node::Expr(&hir::Expr { kind: hir::ExprKind::InlineAsm(asm), span, .. })
297 | Node::Item(&hir::Item { kind: hir::ItemKind::GlobalAsm { asm, .. }, span, .. }) => {
298 asm.operands.iter().find_map(|(op, _op_sp)| match op {
299 hir::InlineAsmOperand::Const { anon_const } if anon_const.hir_id == id => {
300 Some(fcx.next_ty_var(span))
301 }
302 _ => None,
303 })
304 }
305 _ => None,
306 }
307 } else {
308 None
309 };
310 expected_type
311}
312
313#[derive(Debug, PartialEq, Copy, Clone)]
317struct CoroutineTypes<'tcx> {
318 resume_ty: Ty<'tcx>,
320
321 yield_ty: Ty<'tcx>,
323}
324
325#[derive(Copy, Clone, Debug, PartialEq, Eq)]
326pub enum Needs {
327 MutPlace,
328 None,
329}
330
331impl Needs {
332 fn maybe_mut_place(m: hir::Mutability) -> Self {
333 match m {
334 hir::Mutability::Mut => Needs::MutPlace,
335 hir::Mutability::Not => Needs::None,
336 }
337 }
338}
339
340#[derive(Debug, Copy, Clone)]
341pub enum PlaceOp {
342 Deref,
343 Index,
344}
345
346pub struct BreakableCtxt<'tcx> {
347 may_break: bool,
348
349 coerce: Option<DynamicCoerceMany<'tcx>>,
352}
353
354pub struct EnclosingBreakables<'tcx> {
355 stack: Vec<BreakableCtxt<'tcx>>,
356 by_id: HirIdMap<usize>,
357}
358
359impl<'tcx> EnclosingBreakables<'tcx> {
360 fn find_breakable(&mut self, target_id: HirId) -> &mut BreakableCtxt<'tcx> {
361 self.opt_find_breakable(target_id).unwrap_or_else(|| {
362 bug!("could not find enclosing breakable with id {}", target_id);
363 })
364 }
365
366 fn opt_find_breakable(&mut self, target_id: HirId) -> Option<&mut BreakableCtxt<'tcx>> {
367 match self.by_id.get(&target_id) {
368 Some(ix) => Some(&mut self.stack[*ix]),
369 None => None,
370 }
371 }
372}
373
374fn report_unexpected_variant_res(
375 tcx: TyCtxt<'_>,
376 res: Res,
377 expr: Option<&hir::Expr<'_>>,
378 qpath: &hir::QPath<'_>,
379 span: Span,
380 err_code: ErrCode,
381 expected: &str,
382) -> ErrorGuaranteed {
383 let res_descr = match res {
384 Res::Def(DefKind::Variant, _) => "struct variant",
385 _ => res.descr(),
386 };
387 let path_str = rustc_hir_pretty::qpath_to_string(&tcx, qpath);
388 let mut err = tcx
389 .dcx()
390 .struct_span_err(span, format!("expected {expected}, found {res_descr} `{path_str}`"))
391 .with_code(err_code);
392 match res {
393 Res::Def(DefKind::Fn | DefKind::AssocFn, _) if err_code == E0164 => {
394 let patterns_url = "https://doc.rust-lang.org/book/ch19-00-patterns.html";
395 err.with_span_label(span, "`fn` calls are not allowed in patterns")
396 .with_help(format!("for more information, visit {patterns_url}"))
397 }
398 Res::Def(DefKind::Variant, _) if let Some(expr) = expr => {
399 err.span_label(span, format!("not a {expected}"));
400 let variant = tcx.expect_variant_res(res);
401 let sugg = if variant.fields.is_empty() {
402 " {}".to_string()
403 } else {
404 format!(
405 " {{ {} }}",
406 variant
407 .fields
408 .iter()
409 .map(|f| format!("{}: /* value */", f.name))
410 .collect::<Vec<_>>()
411 .join(", ")
412 )
413 };
414 let descr = "you might have meant to create a new value of the struct";
415 let mut suggestion = vec![];
416 match tcx.parent_hir_node(expr.hir_id) {
417 hir::Node::Expr(hir::Expr {
418 kind: hir::ExprKind::Call(..),
419 span: call_span,
420 ..
421 }) => {
422 suggestion.push((span.shrink_to_hi().with_hi(call_span.hi()), sugg));
423 }
424 hir::Node::Expr(hir::Expr { kind: hir::ExprKind::Binary(..), hir_id, .. }) => {
425 suggestion.push((expr.span.shrink_to_lo(), "(".to_string()));
426 if let hir::Node::Expr(drop_temps) = tcx.parent_hir_node(*hir_id)
427 && let hir::ExprKind::DropTemps(_) = drop_temps.kind
428 && let hir::Node::Expr(parent) = tcx.parent_hir_node(drop_temps.hir_id)
429 && let hir::ExprKind::If(condition, block, None) = parent.kind
430 && condition.hir_id == drop_temps.hir_id
431 && let hir::ExprKind::Block(block, _) = block.kind
432 && block.stmts.is_empty()
433 && let Some(expr) = block.expr
434 && let hir::ExprKind::Path(..) = expr.kind
435 {
436 suggestion.push((block.span.shrink_to_hi(), ")".to_string()));
441 } else {
442 suggestion.push((span.shrink_to_hi().with_hi(expr.span.hi()), sugg));
443 }
444 }
445 _ => {
446 suggestion.push((span.shrink_to_hi(), sugg));
447 }
448 }
449
450 err.multipart_suggestion_verbose(descr, suggestion, Applicability::HasPlaceholders);
451 err
452 }
453 Res::Def(DefKind::Variant, _) if expr.is_none() => {
454 err.span_label(span, format!("not a {expected}"));
455
456 let fields = &tcx.expect_variant_res(res).fields.raw;
457 let span = qpath.span().shrink_to_hi().to(span.shrink_to_hi());
458 let (msg, sugg) = if fields.is_empty() {
459 ("use the struct variant pattern syntax".to_string(), " {}".to_string())
460 } else {
461 let msg = format!(
462 "the struct variant's field{s} {are} being ignored",
463 s = pluralize!(fields.len()),
464 are = pluralize!("is", fields.len())
465 );
466 let fields = fields
467 .iter()
468 .map(|field| format!("{}: _", field.ident(tcx)))
469 .collect::<Vec<_>>()
470 .join(", ");
471 let sugg = format!(" {{ {} }}", fields);
472 (msg, sugg)
473 };
474
475 err.span_suggestion_verbose(
476 qpath.span().shrink_to_hi().to(span.shrink_to_hi()),
477 msg,
478 sugg,
479 Applicability::HasPlaceholders,
480 );
481 err
482 }
483 _ => err.with_span_label(span, format!("not a {expected}")),
484 }
485 .emit()
486}
487
488#[derive(Copy, Clone, Eq, PartialEq)]
508enum TupleArgumentsFlag {
509 DontTupleArguments,
510 TupleArguments,
511}
512
513fn fatally_break_rust(tcx: TyCtxt<'_>, span: Span) -> ! {
514 let dcx = tcx.dcx();
515 let mut diag = dcx.struct_span_bug(
516 span,
517 "It looks like you're trying to break rust; would you like some ICE?",
518 );
519 diag.note("the compiler expectedly panicked. this is a feature.");
520 diag.note(
521 "we would appreciate a joke overview: \
522 https://github.com/rust-lang/rust/issues/43162#issuecomment-320764675",
523 );
524 diag.note(format!("rustc {} running on {}", tcx.sess.cfg_version, config::host_tuple(),));
525 if let Some((flags, excluded_cargo_defaults)) = rustc_session::utils::extra_compiler_flags() {
526 diag.note(format!("compiler flags: {}", flags.join(" ")));
527 if excluded_cargo_defaults {
528 diag.note("some of the compiler flags provided by cargo are hidden");
529 }
530 }
531 diag.emit()
532}
533
534pub fn provide(providers: &mut Providers) {
535 method::provide(providers);
536 *providers = Providers { typeck, used_trait_imports, ..*providers };
537}