]>
Commit | Line | Data |
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1a4d82fc JJ |
1 | // Type resolution: the phase that finds all the types in the AST with |
2 | // unresolved type variables and replaces "ty_var" types with their | |
3 | // substitutions. | |
1a4d82fc | 4 | |
2b03887a | 5 | use crate::FnCtxt; |
064997fb FG |
6 | use hir::def_id::LocalDefId; |
7 | use rustc_data_structures::fx::FxHashMap; | |
5e7ed085 | 8 | use rustc_errors::ErrorGuaranteed; |
dfeec247 | 9 | use rustc_hir as hir; |
5099ac24 | 10 | use rustc_hir::intravisit::{self, Visitor}; |
74b04a01 XL |
11 | use rustc_infer::infer::error_reporting::TypeAnnotationNeeded::E0282; |
12 | use rustc_infer::infer::InferCtxt; | |
6a06907d XL |
13 | use rustc_middle::hir::place::Place as HirPlace; |
14 | use rustc_middle::mir::FakeReadCause; | |
ba9703b0 | 15 | use rustc_middle::ty::adjustment::{Adjust, Adjustment, PointerCast}; |
923072b8 | 16 | use rustc_middle::ty::fold::{TypeFoldable, TypeFolder, TypeSuperFoldable}; |
9ffffee4 | 17 | use rustc_middle::ty::visit::{TypeSuperVisitable, TypeVisitable, TypeVisitableExt}; |
f2b60f7d | 18 | use rustc_middle::ty::TypeckResults; |
136023e0 | 19 | use rustc_middle::ty::{self, ClosureSizeProfileData, Ty, TyCtxt}; |
dfeec247 XL |
20 | use rustc_span::symbol::sym; |
21 | use rustc_span::Span; | |
1a4d82fc | 22 | |
60c5eb7d | 23 | use std::mem; |
5e7ed085 | 24 | use std::ops::ControlFlow; |
60c5eb7d | 25 | |
1a4d82fc | 26 | /////////////////////////////////////////////////////////////////////////// |
32a655c1 | 27 | // Entry point |
1a4d82fc | 28 | |
0731742a XL |
29 | // During type inference, partially inferred types are |
30 | // represented using Type variables (ty::Infer). These don't appear in | |
3dfed10e XL |
31 | // the final TypeckResults since all of the types should have been |
32 | // inferred once typeck is done. | |
0731742a | 33 | // When type inference is running however, having to update the typeck |
3dfed10e | 34 | // typeck results every time a new type is inferred would be unreasonably slow, |
0731742a XL |
35 | // so instead all of the replacement happens at the end in |
36 | // resolve_type_vars_in_body, which creates a new TypeTables which | |
37 | // doesn't contain any inference types. | |
dc9dc135 | 38 | impl<'a, 'tcx> FnCtxt<'a, 'tcx> { |
dfeec247 XL |
39 | pub fn resolve_type_vars_in_body( |
40 | &self, | |
41 | body: &'tcx hir::Body<'tcx>, | |
3dfed10e | 42 | ) -> &'tcx ty::TypeckResults<'tcx> { |
9ffffee4 | 43 | let item_def_id = self.tcx.hir().body_owner_def_id(body.id()); |
32a655c1 | 44 | |
b7449926 | 45 | // This attribute causes us to dump some writeback information |
5099ac24 | 46 | // in the form of errors, which is used for unit tests. |
f9f354fc XL |
47 | let rustc_dump_user_substs = |
48 | self.tcx.has_attr(item_def_id.to_def_id(), sym::rustc_dump_user_substs); | |
b7449926 XL |
49 | |
50 | let mut wbcx = WritebackCx::new(self, body, rustc_dump_user_substs); | |
dfeec247 | 51 | for param in body.params { |
e1599b0c | 52 | wbcx.visit_node_id(param.pat.span, param.hir_id); |
1a4d82fc | 53 | } |
48663c56 | 54 | // Type only exists for constants and statics, not functions. |
5e7ed085 | 55 | match self.tcx.hir().body_owner_kind(item_def_id) { |
48663c56 | 56 | hir::BodyOwnerKind::Const | hir::BodyOwnerKind::Static(_) => { |
9ffffee4 FG |
57 | let item_hir_id = self.tcx.hir().local_def_id_to_hir_id(item_def_id); |
58 | wbcx.visit_node_id(body.value.span, item_hir_id); | |
48663c56 XL |
59 | } |
60 | hir::BodyOwnerKind::Closure | hir::BodyOwnerKind::Fn => (), | |
61 | } | |
32a655c1 | 62 | wbcx.visit_body(body); |
fc512014 | 63 | wbcx.visit_min_capture_map(); |
136023e0 | 64 | wbcx.eval_closure_size(); |
6a06907d | 65 | wbcx.visit_fake_reads_map(); |
a7813a04 XL |
66 | wbcx.visit_closures(); |
67 | wbcx.visit_liberated_fn_sigs(); | |
68 | wbcx.visit_fru_field_types(); | |
5e7ed085 | 69 | wbcx.visit_opaque_types(); |
532ac7d7 | 70 | wbcx.visit_coercion_casts(); |
0531ce1d | 71 | wbcx.visit_user_provided_tys(); |
0bf4aa26 | 72 | wbcx.visit_user_provided_sigs(); |
e1599b0c | 73 | wbcx.visit_generator_interior_types(); |
8bb4bdeb | 74 | |
923072b8 FG |
75 | wbcx.typeck_results.rvalue_scopes = |
76 | mem::take(&mut self.typeck_results.borrow_mut().rvalue_scopes); | |
77 | ||
3dfed10e XL |
78 | let used_trait_imports = |
79 | mem::take(&mut self.typeck_results.borrow_mut().used_trait_imports); | |
dfeec247 | 80 | debug!("used_trait_imports({:?}) = {:?}", item_def_id, used_trait_imports); |
3dfed10e | 81 | wbcx.typeck_results.used_trait_imports = used_trait_imports; |
32a655c1 | 82 | |
29967ef6 XL |
83 | wbcx.typeck_results.treat_byte_string_as_slice = |
84 | mem::take(&mut self.typeck_results.borrow_mut().treat_byte_string_as_slice); | |
85 | ||
487cf647 FG |
86 | if let Some(e) = self.tainted_by_errors() { |
87 | wbcx.typeck_results.tainted_by_errors = Some(e); | |
ba9703b0 | 88 | } |
8bb4bdeb | 89 | |
3dfed10e | 90 | debug!("writeback: typeck results for {:?} are {:#?}", item_def_id, wbcx.typeck_results); |
ff7c6d11 | 91 | |
3dfed10e | 92 | self.tcx.arena.alloc(wbcx.typeck_results) |
1a4d82fc | 93 | } |
1a4d82fc JJ |
94 | } |
95 | ||
96 | /////////////////////////////////////////////////////////////////////////// | |
fc512014 | 97 | // The Writeback context. This visitor walks the HIR, checking the |
3dfed10e | 98 | // fn-specific typeck results to find references to types or regions. It |
1a4d82fc | 99 | // resolves those regions to remove inference variables and writes the |
3dfed10e | 100 | // final result back into the master typeck results in the tcx. Here and |
1a4d82fc JJ |
101 | // there, it applies a few ad-hoc checks that were not convenient to |
102 | // do elsewhere. | |
103 | ||
dc9dc135 XL |
104 | struct WritebackCx<'cx, 'tcx> { |
105 | fcx: &'cx FnCtxt<'cx, 'tcx>, | |
5bcae85e | 106 | |
3dfed10e | 107 | typeck_results: ty::TypeckResults<'tcx>, |
32a655c1 | 108 | |
dfeec247 | 109 | body: &'tcx hir::Body<'tcx>, |
b7449926 XL |
110 | |
111 | rustc_dump_user_substs: bool, | |
1a4d82fc JJ |
112 | } |
113 | ||
dc9dc135 | 114 | impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> { |
ff7c6d11 | 115 | fn new( |
dc9dc135 | 116 | fcx: &'cx FnCtxt<'cx, 'tcx>, |
dfeec247 | 117 | body: &'tcx hir::Body<'tcx>, |
b7449926 | 118 | rustc_dump_user_substs: bool, |
dc9dc135 | 119 | ) -> WritebackCx<'cx, 'tcx> { |
ba9703b0 | 120 | let owner = body.id().hir_id.owner; |
3b2f2976 | 121 | |
3dfed10e XL |
122 | WritebackCx { |
123 | fcx, | |
124 | typeck_results: ty::TypeckResults::new(owner), | |
125 | body, | |
126 | rustc_dump_user_substs, | |
127 | } | |
1a4d82fc JJ |
128 | } |
129 | ||
dc9dc135 | 130 | fn tcx(&self) -> TyCtxt<'tcx> { |
a7813a04 | 131 | self.fcx.tcx |
1a4d82fc | 132 | } |
d9579d0f | 133 | |
3dfed10e XL |
134 | fn write_ty_to_typeck_results(&mut self, hir_id: hir::HirId, ty: Ty<'tcx>) { |
135 | debug!("write_ty_to_typeck_results({:?}, {:?})", hir_id, ty); | |
5099ac24 | 136 | assert!(!ty.needs_infer() && !ty.has_placeholders() && !ty.has_free_regions()); |
3dfed10e | 137 | self.typeck_results.node_types_mut().insert(hir_id, ty); |
476ff2be SL |
138 | } |
139 | ||
d9579d0f AL |
140 | // Hacky hack: During type-checking, we treat *all* operators |
141 | // as potentially overloaded. But then, during writeback, if | |
142 | // we observe that something like `a+b` is (known to be) | |
143 | // operating on scalars, we clear the overload. | |
dfeec247 | 144 | fn fix_scalar_builtin_expr(&mut self, e: &hir::Expr<'_>) { |
e74abb32 | 145 | match e.kind { |
c295e0f8 | 146 | hir::ExprKind::Unary(hir::UnOp::Neg | hir::UnOp::Not, inner) => { |
3b2f2976 | 147 | let inner_ty = self.fcx.node_ty(inner.hir_id); |
fc512014 | 148 | let inner_ty = self.fcx.resolve_vars_if_possible(inner_ty); |
32a655c1 SL |
149 | |
150 | if inner_ty.is_scalar() { | |
3dfed10e XL |
151 | let mut typeck_results = self.fcx.typeck_results.borrow_mut(); |
152 | typeck_results.type_dependent_defs_mut().remove(e.hir_id); | |
153 | typeck_results.node_substs_mut().remove(e.hir_id); | |
32a655c1 SL |
154 | } |
155 | } | |
c295e0f8 | 156 | hir::ExprKind::Binary(ref op, lhs, rhs) | hir::ExprKind::AssignOp(ref op, lhs, rhs) => { |
3b2f2976 | 157 | let lhs_ty = self.fcx.node_ty(lhs.hir_id); |
fc512014 | 158 | let lhs_ty = self.fcx.resolve_vars_if_possible(lhs_ty); |
b039eaaf | 159 | |
3b2f2976 | 160 | let rhs_ty = self.fcx.node_ty(rhs.hir_id); |
fc512014 | 161 | let rhs_ty = self.fcx.resolve_vars_if_possible(rhs_ty); |
b039eaaf SL |
162 | |
163 | if lhs_ty.is_scalar() && rhs_ty.is_scalar() { | |
3dfed10e XL |
164 | let mut typeck_results = self.fcx.typeck_results.borrow_mut(); |
165 | typeck_results.type_dependent_defs_mut().remove(e.hir_id); | |
166 | typeck_results.node_substs_mut().remove(e.hir_id); | |
b039eaaf | 167 | |
e74abb32 | 168 | match e.kind { |
8faf50e0 | 169 | hir::ExprKind::Binary(..) => { |
54a0048b | 170 | if !op.node.is_by_value() { |
3dfed10e | 171 | let mut adjustments = typeck_results.adjustments_mut(); |
f9f354fc XL |
172 | if let Some(a) = adjustments.get_mut(lhs.hir_id) { |
173 | a.pop(); | |
174 | } | |
175 | if let Some(a) = adjustments.get_mut(rhs.hir_id) { | |
176 | a.pop(); | |
177 | } | |
b039eaaf | 178 | } |
ff7c6d11 | 179 | } |
94222f64 XL |
180 | hir::ExprKind::AssignOp(..) |
181 | if let Some(a) = typeck_results.adjustments_mut().get_mut(lhs.hir_id) => | |
182 | { | |
183 | a.pop(); | |
ff7c6d11 XL |
184 | } |
185 | _ => {} | |
b039eaaf | 186 | } |
d9579d0f AL |
187 | } |
188 | } | |
ff7c6d11 | 189 | _ => {} |
d9579d0f AL |
190 | } |
191 | } | |
2c00a5a8 | 192 | |
f2b60f7d FG |
193 | // (ouz-a 1005988): Normally `[T] : std::ops::Index<usize>` should be normalized |
194 | // into [T] but currently `Where` clause stops the normalization process for it, | |
195 | // here we compare types of expr and base in a code without `Where` clause they would be equal | |
196 | // if they are not we don't modify the expr, hence we bypass the ICE | |
197 | fn is_builtin_index( | |
198 | &mut self, | |
199 | typeck_results: &TypeckResults<'tcx>, | |
200 | e: &hir::Expr<'_>, | |
201 | base_ty: Ty<'tcx>, | |
202 | index_ty: Ty<'tcx>, | |
203 | ) -> bool { | |
204 | if let Some(elem_ty) = base_ty.builtin_index() { | |
205 | let Some(exp_ty) = typeck_results.expr_ty_opt(e) else {return false;}; | |
206 | let resolved_exp_ty = self.resolve(exp_ty, &e.span); | |
207 | ||
208 | elem_ty == resolved_exp_ty && index_ty == self.fcx.tcx.types.usize | |
209 | } else { | |
210 | false | |
211 | } | |
212 | } | |
213 | ||
2c00a5a8 XL |
214 | // Similar to operators, indexing is always assumed to be overloaded |
215 | // Here, correct cases where an indexing expression can be simplified | |
216 | // to use builtin indexing because the index type is known to be | |
217 | // usize-ish | |
dfeec247 | 218 | fn fix_index_builtin_expr(&mut self, e: &hir::Expr<'_>) { |
e74abb32 | 219 | if let hir::ExprKind::Index(ref base, ref index) = e.kind { |
3dfed10e | 220 | let mut typeck_results = self.fcx.typeck_results.borrow_mut(); |
2c00a5a8 | 221 | |
e74abb32 | 222 | // All valid indexing looks like this; might encounter non-valid indexes at this point. |
fc512014 | 223 | let base_ty = typeck_results |
c295e0f8 | 224 | .expr_ty_adjusted_opt(base) |
fc512014 | 225 | .map(|t| self.fcx.resolve_vars_if_possible(t).kind()); |
e74abb32 XL |
226 | if base_ty.is_none() { |
227 | // When encountering `return [0][0]` outside of a `fn` body we can encounter a base | |
228 | // that isn't in the type table. We assume more relevant errors have already been | |
229 | // emitted, so we delay an ICE if none have. (#64638) | |
230 | self.tcx().sess.delay_span_bug(e.span, &format!("bad base: `{:?}`", base)); | |
231 | } | |
232 | if let Some(ty::Ref(_, base_ty, _)) = base_ty { | |
c295e0f8 | 233 | let index_ty = typeck_results.expr_ty_adjusted_opt(index).unwrap_or_else(|| { |
e74abb32 | 234 | // When encountering `return [0][0]` outside of a `fn` body we would attempt |
5e7ed085 | 235 | // to access an nonexistent index. We assume that more relevant errors will |
e74abb32 XL |
236 | // already have been emitted, so we only gate on this with an ICE if no |
237 | // error has been emitted. (#64638) | |
f035d41b | 238 | self.fcx.tcx.ty_error_with_message( |
e74abb32 XL |
239 | e.span, |
240 | &format!("bad index {:?} for base: `{:?}`", index, base), | |
f035d41b | 241 | ) |
e74abb32 | 242 | }); |
fc512014 | 243 | let index_ty = self.fcx.resolve_vars_if_possible(index_ty); |
f2b60f7d | 244 | let resolved_base_ty = self.resolve(*base_ty, &base.span); |
0bf4aa26 | 245 | |
f2b60f7d | 246 | if self.is_builtin_index(&typeck_results, e, resolved_base_ty, index_ty) { |
0bf4aa26 | 247 | // Remove the method call record |
3dfed10e XL |
248 | typeck_results.type_dependent_defs_mut().remove(e.hir_id); |
249 | typeck_results.node_substs_mut().remove(e.hir_id); | |
0bf4aa26 | 250 | |
3dfed10e | 251 | if let Some(a) = typeck_results.adjustments_mut().get_mut(base.hir_id) { |
0bf4aa26 | 252 | // Discard the need for a mutable borrow |
ba9703b0 XL |
253 | |
254 | // Extra adjustment made when indexing causes a drop | |
255 | // of size information - we need to get rid of it | |
256 | // Since this is "after" the other adjustment to be | |
257 | // discarded, we do an extra `pop()` | |
258 | if let Some(Adjustment { | |
259 | kind: Adjust::Pointer(PointerCast::Unsize), .. | |
260 | }) = a.pop() | |
261 | { | |
262 | // So the borrow discard actually happens here | |
263 | a.pop(); | |
0bf4aa26 | 264 | } |
f9f354fc | 265 | } |
b7449926 | 266 | } |
2c00a5a8 XL |
267 | } |
268 | } | |
269 | } | |
1a4d82fc JJ |
270 | } |
271 | ||
272 | /////////////////////////////////////////////////////////////////////////// | |
273 | // Impl of Visitor for Resolver | |
274 | // | |
275 | // This is the master code which walks the AST. It delegates most of | |
276 | // the heavy lifting to the generic visit and resolve functions | |
277 | // below. In general, a function is made into a `visitor` if it must | |
3dfed10e | 278 | // traffic in node-ids or update typeck results in the type context etc. |
1a4d82fc | 279 | |
dc9dc135 | 280 | impl<'cx, 'tcx> Visitor<'tcx> for WritebackCx<'cx, 'tcx> { |
dfeec247 | 281 | fn visit_expr(&mut self, e: &'tcx hir::Expr<'tcx>) { |
32a655c1 | 282 | self.fix_scalar_builtin_expr(e); |
2c00a5a8 | 283 | self.fix_index_builtin_expr(e); |
c34b1796 | 284 | |
e74abb32 | 285 | match e.kind { |
064997fb | 286 | hir::ExprKind::Closure(&hir::Closure { body, .. }) => { |
0731742a | 287 | let body = self.fcx.tcx.hir().body(body); |
dfeec247 | 288 | for param in body.params { |
e1599b0c | 289 | self.visit_node_id(e.span, param.hir_id); |
83c7162d | 290 | } |
32a655c1 | 291 | |
83c7162d XL |
292 | self.visit_body(body); |
293 | } | |
dfeec247 | 294 | hir::ExprKind::Struct(_, fields, _) => { |
83c7162d | 295 | for field in fields { |
532ac7d7 | 296 | self.visit_field_id(field.hir_id); |
83c7162d XL |
297 | } |
298 | } | |
8faf50e0 | 299 | hir::ExprKind::Field(..) => { |
532ac7d7 | 300 | self.visit_field_id(e.hir_id); |
83c7162d | 301 | } |
3c0e092e XL |
302 | hir::ExprKind::ConstBlock(anon_const) => { |
303 | self.visit_node_id(e.span, anon_const.hir_id); | |
304 | ||
305 | let body = self.tcx().hir().body(anon_const.body); | |
306 | self.visit_body(body); | |
307 | } | |
83c7162d | 308 | _ => {} |
1a4d82fc JJ |
309 | } |
310 | ||
923072b8 | 311 | self.visit_node_id(e.span, e.hir_id); |
92a42be0 | 312 | intravisit::walk_expr(self, e); |
1a4d82fc JJ |
313 | } |
314 | ||
f2b60f7d FG |
315 | fn visit_generic_param(&mut self, p: &'tcx hir::GenericParam<'tcx>) { |
316 | match &p.kind { | |
317 | hir::GenericParamKind::Lifetime { .. } => { | |
318 | // Nothing to write back here | |
319 | } | |
320 | hir::GenericParamKind::Type { .. } | hir::GenericParamKind::Const { .. } => { | |
321 | self.tcx().sess.delay_span_bug(p.span, format!("unexpected generic param: {p:?}")); | |
322 | } | |
323 | } | |
324 | } | |
325 | ||
dfeec247 | 326 | fn visit_block(&mut self, b: &'tcx hir::Block<'tcx>) { |
3b2f2976 | 327 | self.visit_node_id(b.span, b.hir_id); |
92a42be0 | 328 | intravisit::walk_block(self, b); |
1a4d82fc JJ |
329 | } |
330 | ||
dfeec247 | 331 | fn visit_pat(&mut self, p: &'tcx hir::Pat<'tcx>) { |
e74abb32 | 332 | match p.kind { |
3b2f2976 | 333 | hir::PatKind::Binding(..) => { |
3dfed10e XL |
334 | let typeck_results = self.fcx.typeck_results.borrow(); |
335 | if let Some(bm) = | |
336 | typeck_results.extract_binding_mode(self.tcx().sess, p.hir_id, p.span) | |
337 | { | |
338 | self.typeck_results.pat_binding_modes_mut().insert(p.hir_id, bm); | |
8faf50e0 | 339 | } |
3b2f2976 | 340 | } |
dfeec247 | 341 | hir::PatKind::Struct(_, fields, _) => { |
83c7162d | 342 | for field in fields { |
e1599b0c | 343 | self.visit_field_id(field.hir_id); |
83c7162d XL |
344 | } |
345 | } | |
3b2f2976 XL |
346 | _ => {} |
347 | }; | |
348 | ||
ea8adc8c XL |
349 | self.visit_pat_adjustments(p.span, p.hir_id); |
350 | ||
3b2f2976 | 351 | self.visit_node_id(p.span, p.hir_id); |
92a42be0 | 352 | intravisit::walk_pat(self, p); |
1a4d82fc JJ |
353 | } |
354 | ||
dfeec247 | 355 | fn visit_local(&mut self, l: &'tcx hir::Local<'tcx>) { |
cc61c64b | 356 | intravisit::walk_local(self, l); |
532ac7d7 | 357 | let var_ty = self.fcx.local_ty(l.span, l.hir_id).decl_ty; |
fc512014 | 358 | let var_ty = self.resolve(var_ty, &l.span); |
3dfed10e | 359 | self.write_ty_to_typeck_results(l.hir_id, var_ty); |
1a4d82fc | 360 | } |
ea8adc8c | 361 | |
dfeec247 | 362 | fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty<'tcx>) { |
ea8adc8c | 363 | intravisit::walk_ty(self, hir_ty); |
487cf647 FG |
364 | // If there are type checking errors, Type privacy pass will stop, |
365 | // so we may not get the type from hid_id, see #104513 | |
366 | if let Some(ty) = self.fcx.node_ty_opt(hir_ty.hir_id) { | |
367 | let ty = self.resolve(ty, &hir_ty.span); | |
368 | self.write_ty_to_typeck_results(hir_ty.hir_id, ty); | |
369 | } | |
ea8adc8c | 370 | } |
94222f64 XL |
371 | |
372 | fn visit_infer(&mut self, inf: &'tcx hir::InferArg) { | |
373 | intravisit::walk_inf(self, inf); | |
374 | // Ignore cases where the inference is a const. | |
375 | if let Some(ty) = self.fcx.node_ty_opt(inf.hir_id) { | |
376 | let ty = self.resolve(ty, &inf.span); | |
377 | self.write_ty_to_typeck_results(inf.hir_id, ty); | |
378 | } | |
379 | } | |
1a4d82fc JJ |
380 | } |
381 | ||
dc9dc135 | 382 | impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> { |
136023e0 | 383 | fn eval_closure_size(&mut self) { |
064997fb FG |
384 | let mut res: FxHashMap<LocalDefId, ClosureSizeProfileData<'tcx>> = Default::default(); |
385 | for (&closure_def_id, data) in self.fcx.typeck_results.borrow().closure_size_eval.iter() { | |
386 | let closure_hir_id = self.tcx().hir().local_def_id_to_hir_id(closure_def_id); | |
136023e0 XL |
387 | |
388 | let data = self.resolve(*data, &closure_hir_id); | |
389 | ||
064997fb | 390 | res.insert(closure_def_id, data); |
136023e0 XL |
391 | } |
392 | ||
393 | self.typeck_results.closure_size_eval = res; | |
394 | } | |
fc512014 XL |
395 | fn visit_min_capture_map(&mut self) { |
396 | let mut min_captures_wb = ty::MinCaptureInformationMap::with_capacity_and_hasher( | |
397 | self.fcx.typeck_results.borrow().closure_min_captures.len(), | |
398 | Default::default(), | |
399 | ); | |
064997fb | 400 | for (&closure_def_id, root_min_captures) in |
fc512014 XL |
401 | self.fcx.typeck_results.borrow().closure_min_captures.iter() |
402 | { | |
403 | let mut root_var_map_wb = ty::RootVariableMinCaptureList::with_capacity_and_hasher( | |
404 | root_min_captures.len(), | |
405 | Default::default(), | |
406 | ); | |
407 | for (var_hir_id, min_list) in root_min_captures.iter() { | |
408 | let min_list_wb = min_list | |
409 | .iter() | |
410 | .map(|captured_place| { | |
6a06907d | 411 | let locatable = captured_place.info.path_expr_id.unwrap_or_else(|| { |
064997fb | 412 | self.tcx().hir().local_def_id_to_hir_id(closure_def_id) |
6a06907d | 413 | }); |
fc512014 XL |
414 | |
415 | self.resolve(captured_place.clone(), &locatable) | |
416 | }) | |
417 | .collect(); | |
418 | root_var_map_wb.insert(*var_hir_id, min_list_wb); | |
419 | } | |
064997fb | 420 | min_captures_wb.insert(closure_def_id, root_var_map_wb); |
fc512014 XL |
421 | } |
422 | ||
423 | self.typeck_results.closure_min_captures = min_captures_wb; | |
424 | } | |
425 | ||
6a06907d XL |
426 | fn visit_fake_reads_map(&mut self) { |
427 | let mut resolved_closure_fake_reads: FxHashMap< | |
064997fb | 428 | LocalDefId, |
6a06907d XL |
429 | Vec<(HirPlace<'tcx>, FakeReadCause, hir::HirId)>, |
430 | > = Default::default(); | |
064997fb | 431 | for (&closure_def_id, fake_reads) in |
6a06907d XL |
432 | self.fcx.typeck_results.borrow().closure_fake_reads.iter() |
433 | { | |
434 | let mut resolved_fake_reads = Vec::<(HirPlace<'tcx>, FakeReadCause, hir::HirId)>::new(); | |
435 | for (place, cause, hir_id) in fake_reads.iter() { | |
064997fb | 436 | let locatable = self.tcx().hir().local_def_id_to_hir_id(closure_def_id); |
6a06907d XL |
437 | |
438 | let resolved_fake_read = self.resolve(place.clone(), &locatable); | |
439 | resolved_fake_reads.push((resolved_fake_read, *cause, *hir_id)); | |
440 | } | |
064997fb | 441 | resolved_closure_fake_reads.insert(closure_def_id, resolved_fake_reads); |
1a4d82fc | 442 | } |
6a06907d | 443 | self.typeck_results.closure_fake_reads = resolved_closure_fake_reads; |
1a4d82fc JJ |
444 | } |
445 | ||
8bb4bdeb | 446 | fn visit_closures(&mut self) { |
3dfed10e XL |
447 | let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
448 | assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); | |
449 | let common_hir_owner = fcx_typeck_results.hir_owner; | |
3b2f2976 | 450 | |
9c376795 FG |
451 | let fcx_closure_kind_origins = |
452 | fcx_typeck_results.closure_kind_origins().items_in_stable_order(); | |
453 | ||
454 | for (local_id, origin) in fcx_closure_kind_origins { | |
455 | let hir_id = hir::HirId { owner: common_hir_owner, local_id }; | |
5869c6ff XL |
456 | let place_span = origin.0; |
457 | let place = self.resolve(origin.1.clone(), &place_span); | |
458 | self.typeck_results.closure_kind_origins_mut().insert(hir_id, (place_span, place)); | |
1a4d82fc JJ |
459 | } |
460 | } | |
461 | ||
532ac7d7 | 462 | fn visit_coercion_casts(&mut self) { |
3dfed10e | 463 | let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
9c376795 | 464 | |
3dfed10e | 465 | assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); |
3b2f2976 | 466 | |
9c376795 | 467 | let fcx_coercion_casts = fcx_typeck_results.coercion_casts().to_sorted_stable_ord(); |
532ac7d7 | 468 | for local_id in fcx_coercion_casts { |
9c376795 | 469 | self.typeck_results.set_coercion_cast(local_id); |
3b2f2976 | 470 | } |
8bb4bdeb XL |
471 | } |
472 | ||
0531ce1d | 473 | fn visit_user_provided_tys(&mut self) { |
3dfed10e XL |
474 | let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
475 | assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); | |
476 | let common_hir_owner = fcx_typeck_results.hir_owner; | |
0531ce1d | 477 | |
9c376795 FG |
478 | if self.rustc_dump_user_substs { |
479 | let sorted_user_provided_types = | |
480 | fcx_typeck_results.user_provided_types().items_in_stable_order(); | |
0531ce1d | 481 | |
9c376795 FG |
482 | let mut errors_buffer = Vec::new(); |
483 | for (local_id, c_ty) in sorted_user_provided_types { | |
484 | let hir_id = hir::HirId { owner: common_hir_owner, local_id }; | |
0731742a | 485 | |
9c376795 | 486 | if let ty::UserType::TypeOf(_, user_substs) = c_ty.value { |
0731742a | 487 | // This is a unit-testing mechanism. |
dc9dc135 | 488 | let span = self.tcx().hir().span(hir_id); |
0731742a XL |
489 | // We need to buffer the errors in order to guarantee a consistent |
490 | // order when emitting them. | |
dfeec247 XL |
491 | let err = self |
492 | .tcx() | |
493 | .sess | |
494 | .struct_span_err(span, &format!("user substs: {:?}", user_substs)); | |
0731742a XL |
495 | err.buffer(&mut errors_buffer); |
496 | } | |
497 | } | |
0731742a | 498 | |
9c376795 FG |
499 | if !errors_buffer.is_empty() { |
500 | errors_buffer.sort_by_key(|diag| diag.span.primary_span()); | |
501 | for mut diag in errors_buffer { | |
502 | self.tcx().sess.diagnostic().emit_diagnostic(&mut diag); | |
503 | } | |
0731742a | 504 | } |
0531ce1d | 505 | } |
9c376795 FG |
506 | |
507 | self.typeck_results.user_provided_types_mut().extend( | |
508 | fcx_typeck_results.user_provided_types().items().map(|(local_id, c_ty)| { | |
509 | let hir_id = hir::HirId { owner: common_hir_owner, local_id }; | |
510 | ||
511 | if cfg!(debug_assertions) && c_ty.needs_infer() { | |
512 | span_bug!( | |
513 | hir_id.to_span(self.fcx.tcx), | |
514 | "writeback: `{:?}` has inference variables", | |
515 | c_ty | |
516 | ); | |
517 | }; | |
518 | ||
519 | (hir_id, *c_ty) | |
520 | }), | |
521 | ); | |
0531ce1d XL |
522 | } |
523 | ||
0bf4aa26 | 524 | fn visit_user_provided_sigs(&mut self) { |
3dfed10e XL |
525 | let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
526 | assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); | |
0bf4aa26 | 527 | |
9c376795 FG |
528 | self.typeck_results.user_provided_sigs.extend( |
529 | fcx_typeck_results.user_provided_sigs.items().map(|(&def_id, c_sig)| { | |
530 | if cfg!(debug_assertions) && c_sig.needs_infer() { | |
531 | span_bug!( | |
532 | self.fcx.tcx.def_span(def_id), | |
533 | "writeback: `{:?}` has inference variables", | |
534 | c_sig | |
535 | ); | |
536 | }; | |
537 | ||
538 | (def_id, *c_sig) | |
539 | }), | |
540 | ); | |
0bf4aa26 XL |
541 | } |
542 | ||
e1599b0c | 543 | fn visit_generator_interior_types(&mut self) { |
3dfed10e XL |
544 | let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
545 | assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); | |
546 | self.typeck_results.generator_interior_types = | |
547 | fcx_typeck_results.generator_interior_types.clone(); | |
9ffffee4 FG |
548 | for (&expr_def_id, predicates) in fcx_typeck_results.generator_interior_predicates.iter() { |
549 | let predicates = self.resolve(predicates.clone(), &self.fcx.tcx.def_span(expr_def_id)); | |
550 | self.typeck_results.generator_interior_predicates.insert(expr_def_id, predicates); | |
551 | } | |
e1599b0c XL |
552 | } |
553 | ||
5e7ed085 FG |
554 | #[instrument(skip(self), level = "debug")] |
555 | fn visit_opaque_types(&mut self) { | |
9c376795 | 556 | let opaque_types = self.fcx.infcx.take_opaque_types(); |
5e7ed085 | 557 | for (opaque_type_key, decl) in opaque_types { |
2b03887a FG |
558 | let hidden_type = self.resolve(decl.hidden_type, &decl.hidden_type.span); |
559 | let opaque_type_key = self.resolve(opaque_type_key, &decl.hidden_type.span); | |
560 | ||
561 | struct RecursionChecker { | |
562 | def_id: LocalDefId, | |
563 | } | |
9ffffee4 | 564 | impl<'tcx> ty::TypeVisitor<TyCtxt<'tcx>> for RecursionChecker { |
2b03887a FG |
565 | type BreakTy = (); |
566 | fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> { | |
9c376795 | 567 | if let ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. }) = *t.kind() { |
2b03887a FG |
568 | if def_id == self.def_id.to_def_id() { |
569 | return ControlFlow::Break(()); | |
5e7ed085 | 570 | } |
e74abb32 | 571 | } |
2b03887a | 572 | t.super_visit_with(self) |
b7449926 | 573 | } |
2b03887a FG |
574 | } |
575 | if hidden_type | |
576 | .visit_with(&mut RecursionChecker { def_id: opaque_type_key.def_id }) | |
577 | .is_break() | |
578 | { | |
579 | continue; | |
580 | } | |
581 | ||
582 | let hidden_type = hidden_type.remap_generic_params_to_declaration_params( | |
583 | opaque_type_key, | |
584 | self.fcx.infcx.tcx, | |
585 | true, | |
2b03887a FG |
586 | ); |
587 | ||
5e7ed085 | 588 | self.typeck_results.concrete_opaque_types.insert(opaque_type_key.def_id, hidden_type); |
5bcae85e SL |
589 | } |
590 | } | |
591 | ||
532ac7d7 | 592 | fn visit_field_id(&mut self, hir_id: hir::HirId) { |
3dfed10e XL |
593 | if let Some(index) = self.fcx.typeck_results.borrow_mut().field_indices_mut().remove(hir_id) |
594 | { | |
595 | self.typeck_results.field_indices_mut().insert(hir_id, index); | |
83c7162d XL |
596 | } |
597 | } | |
598 | ||
c295e0f8 | 599 | #[instrument(skip(self, span), level = "debug")] |
3b2f2976 | 600 | fn visit_node_id(&mut self, span: Span, hir_id: hir::HirId) { |
b7449926 | 601 | // Export associated path extensions and method resolutions. |
3dfed10e XL |
602 | if let Some(def) = |
603 | self.fcx.typeck_results.borrow_mut().type_dependent_defs_mut().remove(hir_id) | |
604 | { | |
605 | self.typeck_results.type_dependent_defs_mut().insert(hir_id, def); | |
476ff2be SL |
606 | } |
607 | ||
cc61c64b | 608 | // Resolve any borrowings for the node with id `node_id` |
3b2f2976 | 609 | self.visit_adjustments(span, hir_id); |
1a4d82fc | 610 | |
cc61c64b | 611 | // Resolve the type of the node with id `node_id` |
3b2f2976 | 612 | let n_ty = self.fcx.node_ty(hir_id); |
fc512014 | 613 | let n_ty = self.resolve(n_ty, &span); |
3dfed10e | 614 | self.write_ty_to_typeck_results(hir_id, n_ty); |
c295e0f8 | 615 | debug!(?n_ty); |
1a4d82fc JJ |
616 | |
617 | // Resolve any substitutions | |
3dfed10e | 618 | if let Some(substs) = self.fcx.typeck_results.borrow().node_substs_opt(hir_id) { |
fc512014 | 619 | let substs = self.resolve(substs, &span); |
3b2f2976 | 620 | debug!("write_substs_to_tcx({:?}, {:?})", hir_id, substs); |
a1dfa0c6 | 621 | assert!(!substs.needs_infer() && !substs.has_placeholders()); |
3dfed10e | 622 | self.typeck_results.node_substs_mut().insert(hir_id, substs); |
7cac9316 | 623 | } |
1a4d82fc JJ |
624 | } |
625 | ||
c295e0f8 | 626 | #[instrument(skip(self, span), level = "debug")] |
3b2f2976 | 627 | fn visit_adjustments(&mut self, span: Span, hir_id: hir::HirId) { |
3dfed10e | 628 | let adjustment = self.fcx.typeck_results.borrow_mut().adjustments_mut().remove(hir_id); |
7cac9316 | 629 | match adjustment { |
1a4d82fc | 630 | None => { |
c295e0f8 | 631 | debug!("no adjustments for node"); |
1a4d82fc JJ |
632 | } |
633 | ||
634 | Some(adjustment) => { | |
fc512014 | 635 | let resolved_adjustment = self.resolve(adjustment, &span); |
c295e0f8 | 636 | debug!(?resolved_adjustment); |
3dfed10e | 637 | self.typeck_results.adjustments_mut().insert(hir_id, resolved_adjustment); |
1a4d82fc JJ |
638 | } |
639 | } | |
640 | } | |
641 | ||
c295e0f8 | 642 | #[instrument(skip(self, span), level = "debug")] |
ea8adc8c | 643 | fn visit_pat_adjustments(&mut self, span: Span, hir_id: hir::HirId) { |
3dfed10e | 644 | let adjustment = self.fcx.typeck_results.borrow_mut().pat_adjustments_mut().remove(hir_id); |
ea8adc8c XL |
645 | match adjustment { |
646 | None => { | |
c295e0f8 | 647 | debug!("no pat_adjustments for node"); |
ea8adc8c XL |
648 | } |
649 | ||
650 | Some(adjustment) => { | |
fc512014 | 651 | let resolved_adjustment = self.resolve(adjustment, &span); |
c295e0f8 | 652 | debug!(?resolved_adjustment); |
3dfed10e | 653 | self.typeck_results.pat_adjustments_mut().insert(hir_id, resolved_adjustment); |
ea8adc8c XL |
654 | } |
655 | } | |
656 | } | |
657 | ||
32a655c1 | 658 | fn visit_liberated_fn_sigs(&mut self) { |
3dfed10e XL |
659 | let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
660 | assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); | |
661 | let common_hir_owner = fcx_typeck_results.hir_owner; | |
3b2f2976 | 662 | |
9c376795 FG |
663 | let fcx_liberated_fn_sigs = fcx_typeck_results.liberated_fn_sigs().items_in_stable_order(); |
664 | ||
665 | for (local_id, &fn_sig) in fcx_liberated_fn_sigs { | |
ba9703b0 | 666 | let hir_id = hir::HirId { owner: common_hir_owner, local_id }; |
3b2f2976 | 667 | let fn_sig = self.resolve(fn_sig, &hir_id); |
3dfed10e | 668 | self.typeck_results.liberated_fn_sigs_mut().insert(hir_id, fn_sig); |
92a42be0 SL |
669 | } |
670 | } | |
671 | ||
32a655c1 | 672 | fn visit_fru_field_types(&mut self) { |
3dfed10e XL |
673 | let fcx_typeck_results = self.fcx.typeck_results.borrow(); |
674 | assert_eq!(fcx_typeck_results.hir_owner, self.typeck_results.hir_owner); | |
675 | let common_hir_owner = fcx_typeck_results.hir_owner; | |
3b2f2976 | 676 | |
9c376795 FG |
677 | let fcx_fru_field_types = fcx_typeck_results.fru_field_types().items_in_stable_order(); |
678 | ||
679 | for (local_id, ftys) in fcx_fru_field_types { | |
ba9703b0 | 680 | let hir_id = hir::HirId { owner: common_hir_owner, local_id }; |
fc512014 | 681 | let ftys = self.resolve(ftys.clone(), &hir_id); |
3dfed10e | 682 | self.typeck_results.fru_field_types_mut().insert(hir_id, ftys); |
7453a54e SL |
683 | } |
684 | } | |
685 | ||
fc512014 | 686 | fn resolve<T>(&mut self, x: T, span: &dyn Locatable) -> T |
ff7c6d11 | 687 | where |
9ffffee4 | 688 | T: TypeFoldable<TyCtxt<'tcx>>, |
a7813a04 | 689 | { |
ba9703b0 XL |
690 | let mut resolver = Resolver::new(self.fcx, span, self.body); |
691 | let x = x.fold_with(&mut resolver); | |
692 | if cfg!(debug_assertions) && x.needs_infer() { | |
693 | span_bug!(span.to_span(self.fcx.tcx), "writeback: `{:?}` has inference variables", x); | |
694 | } | |
695 | ||
696 | // We may have introduced e.g. `ty::Error`, if inference failed, make sure | |
3dfed10e XL |
697 | // to mark the `TypeckResults` as tainted in that case, so that downstream |
698 | // users of the typeck results don't produce extra errors, or worse, ICEs. | |
487cf647 FG |
699 | if let Some(e) = resolver.replaced_with_error { |
700 | self.typeck_results.tainted_by_errors = Some(e); | |
a7813a04 | 701 | } |
ba9703b0 | 702 | |
dc9dc135 | 703 | x |
1a4d82fc JJ |
704 | } |
705 | } | |
706 | ||
923072b8 | 707 | pub(crate) trait Locatable { |
dc9dc135 | 708 | fn to_span(&self, tcx: TyCtxt<'_>) -> Span; |
1a4d82fc JJ |
709 | } |
710 | ||
cc61c64b | 711 | impl Locatable for Span { |
dc9dc135 | 712 | fn to_span(&self, _: TyCtxt<'_>) -> Span { |
ff7c6d11 XL |
713 | *self |
714 | } | |
cc61c64b XL |
715 | } |
716 | ||
3b2f2976 | 717 | impl Locatable for hir::HirId { |
dc9dc135 XL |
718 | fn to_span(&self, tcx: TyCtxt<'_>) -> Span { |
719 | tcx.hir().span(*self) | |
3b2f2976 XL |
720 | } |
721 | } | |
722 | ||
ba9703b0 XL |
723 | /// The Resolver. This is the type folding engine that detects |
724 | /// unresolved types and so forth. | |
cdc7bbd5 | 725 | struct Resolver<'cx, 'tcx> { |
dc9dc135 | 726 | tcx: TyCtxt<'tcx>, |
2b03887a | 727 | infcx: &'cx InferCtxt<'tcx>, |
8faf50e0 | 728 | span: &'cx dyn Locatable, |
dfeec247 | 729 | body: &'tcx hir::Body<'tcx>, |
ba9703b0 | 730 | |
487cf647 FG |
731 | /// Set to `Some` if any `Ty` or `ty::Const` had to be replaced with an `Error`. |
732 | replaced_with_error: Option<ErrorGuaranteed>, | |
1a4d82fc JJ |
733 | } |
734 | ||
dc9dc135 | 735 | impl<'cx, 'tcx> Resolver<'cx, 'tcx> { |
cdc7bbd5 | 736 | fn new( |
dc9dc135 | 737 | fcx: &'cx FnCtxt<'cx, 'tcx>, |
8faf50e0 | 738 | span: &'cx dyn Locatable, |
dfeec247 | 739 | body: &'tcx hir::Body<'tcx>, |
dc9dc135 | 740 | ) -> Resolver<'cx, 'tcx> { |
487cf647 | 741 | Resolver { tcx: fcx.tcx, infcx: fcx, span, body, replaced_with_error: None } |
1a4d82fc JJ |
742 | } |
743 | ||
487cf647 FG |
744 | fn report_error(&self, p: impl Into<ty::GenericArg<'tcx>>) -> ErrorGuaranteed { |
745 | match self.tcx.sess.has_errors() { | |
746 | Some(e) => e, | |
747 | None => self | |
748 | .infcx | |
2b03887a | 749 | .err_ctxt() |
1b1a35ee XL |
750 | .emit_inference_failure_err( |
751 | Some(self.body.id()), | |
752 | self.span.to_span(self.tcx), | |
2b03887a | 753 | p.into(), |
f9f354fc | 754 | E0282, |
064997fb | 755 | false, |
f9f354fc | 756 | ) |
487cf647 | 757 | .emit(), |
f9f354fc XL |
758 | } |
759 | } | |
1a4d82fc JJ |
760 | } |
761 | ||
c295e0f8 XL |
762 | struct EraseEarlyRegions<'tcx> { |
763 | tcx: TyCtxt<'tcx>, | |
764 | } | |
765 | ||
9ffffee4 FG |
766 | impl<'tcx> TypeFolder<TyCtxt<'tcx>> for EraseEarlyRegions<'tcx> { |
767 | fn interner(&self) -> TyCtxt<'tcx> { | |
c295e0f8 XL |
768 | self.tcx |
769 | } | |
770 | fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> { | |
5099ac24 | 771 | if ty.has_type_flags(ty::TypeFlags::HAS_FREE_REGIONS) { |
c295e0f8 XL |
772 | ty.super_fold_with(self) |
773 | } else { | |
774 | ty | |
775 | } | |
776 | } | |
777 | fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> { | |
5099ac24 | 778 | if r.is_late_bound() { r } else { self.tcx.lifetimes.re_erased } |
c295e0f8 XL |
779 | } |
780 | } | |
781 | ||
9ffffee4 FG |
782 | impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Resolver<'cx, 'tcx> { |
783 | fn interner(&self) -> TyCtxt<'tcx> { | |
1a4d82fc JJ |
784 | self.tcx |
785 | } | |
786 | ||
787 | fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> { | |
fc512014 | 788 | match self.infcx.fully_resolve(t) { |
c295e0f8 XL |
789 | Ok(t) => { |
790 | // Do not anonymize late-bound regions | |
791 | // (e.g. keep `for<'a>` named `for<'a>`). | |
792 | // This allows NLL to generate error messages that | |
793 | // refer to the higher-ranked lifetime names written by the user. | |
064997fb | 794 | EraseEarlyRegions { tcx: self.tcx }.fold_ty(t) |
c295e0f8 | 795 | } |
cc61c64b | 796 | Err(_) => { |
dfeec247 | 797 | debug!("Resolver::fold_ty: input type `{:?}` not fully resolvable", t); |
487cf647 FG |
798 | let e = self.report_error(t); |
799 | self.replaced_with_error = Some(e); | |
9ffffee4 | 800 | self.interner().ty_error(e) |
1a4d82fc JJ |
801 | } |
802 | } | |
803 | } | |
804 | ||
7cac9316 | 805 | fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> { |
ba9703b0 XL |
806 | debug_assert!(!r.is_late_bound(), "Should not be resolving bound region."); |
807 | self.tcx.lifetimes.re_erased | |
48663c56 XL |
808 | } |
809 | ||
5099ac24 | 810 | fn fold_const(&mut self, ct: ty::Const<'tcx>) -> ty::Const<'tcx> { |
fc512014 | 811 | match self.infcx.fully_resolve(ct) { |
064997fb | 812 | Ok(ct) => self.tcx.erase_regions(ct), |
48663c56 | 813 | Err(_) => { |
dfeec247 | 814 | debug!("Resolver::fold_const: input const `{:?}` not fully resolvable", ct); |
487cf647 FG |
815 | let e = self.report_error(ct); |
816 | self.replaced_with_error = Some(e); | |
9ffffee4 | 817 | self.interner().const_error_with_guaranteed(ct.ty(), e) |
48663c56 XL |
818 | } |
819 | } | |
1a4d82fc JJ |
820 | } |
821 | } | |
822 | ||
823 | /////////////////////////////////////////////////////////////////////////// | |
824 | // During type check, we store promises with the result of trait | |
825 | // lookup rather than the actual results (because the results are not | |
826 | // necessarily available immediately). These routines unwind the | |
827 | // promises. It is expected that we will have already reported any | |
828 | // errors that may be encountered, so if the promises store an error, | |
829 | // a dummy result is returned. |