typeck: taint if errors found during writeback

compiler/rustc_hir_typeck/messages.ftl

@@ -94,5 +94,8 @@ hir_typeck_suggest_ptr_null_mut = consider using `core::ptr::null_mut` instead
 hir_typeck_union_pat_dotdot = `..` cannot be used in union patterns
 
 hir_typeck_union_pat_multiple_fields = union patterns should have exactly one field
+
+hir_typeck_writeback_found_err = found type error in writeback
+
 hir_typeck_yield_expr_outside_of_generator =
  yield expression outside of generator literal

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -467,7 +467,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
  pub fn node_ty_opt(&self, id: hir::HirId) -> Option<Ty<'tcx>> {
  match self.typeck_results.borrow().node_types().get(id) {
  Some(&t) => Some(t),
- None if let Some(e) = self.tainted_by_errors() => Some(Ty::new_error(self.tcx,e)),
+ None if let Some(e) = self.tainted_by_errors() => Some(Ty::new_error(self.tcx, e)),
  None => None,
  }
  }

compiler/rustc_hir_typeck/src/writeback.rs

@@ -2,7 +2,7 @@
 // unresolved type variables and replaces "ty_var" types with their
 // substitutions.
 
-use crate::FnCtxt;
+use crate::{fluent_generated as fluent, FnCtxt};
 use hir::def_id::LocalDefId;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::{ErrorGuaranteed, StashKey};
@@ -134,13 +134,34 @@ impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> {
  self.fcx.tcx
  }
 
+ /// Checks if `ty` contains a `ty::Error` (i.e. `ty.references_error()`), but peering into
+ /// function signatures and ADTs.
+ fn deep_references_error(&self, ty: Ty<'tcx>) -> bool {
+ ty.references_error() || {
+ match ty.kind() {
+ ty::Adt(adt, substs) => {
+ adt.all_fields().any(|field| field.ty(self.tcx(), substs).references_error())
+ }
+ ty::FnDef(..) => ty.fn_sig(self.tcx()).references_error(),
+ _ => false,
+ }
+ }
+ }
+
  fn write_ty_to_typeck_results(&mut self, hir_id: hir::HirId, ty: Ty<'tcx>) {
  debug!("write_ty_to_typeck_results({:?}, {:?})", hir_id, ty);
  assert!(
  !ty.has_infer() && !ty.has_placeholders() && !ty.has_free_regions(),
  "{ty} can't be put into typeck results"
  );
  self.typeck_results.node_types_mut().insert(hir_id, ty);
+ if self.deep_references_error(ty) {
+ self.typeck_results.tainted_by_errors = Some(
+ self.tcx()
+ .sess
+ .delay_span_bug(rustc_span::DUMMY_SP, fluent::hir_typeck_writeback_found_err),
+ );
+ }
  }
 
  // Hacky hack: During type-checking, we treat *all* operators

tests/ui/cast/issue-112630-1.rs

@@ -0,0 +1,6 @@
+fn f(_: B) {}
+//~^ ERROR cannot find type `B` in this scope [E0412]
+
+fn main() {
+ let _ = [0; f as usize];
+}

tests/ui/cast/issue-112630-1.stderr

@@ -0,0 +1,14 @@
+error[E0412]: cannot find type `B` in this scope
+ --> $DIR/issue-112630-1.rs:1:9
+ |
+LL | fn f(_: B) {}
+ | ^ not found in this scope
+ |
+help: you might be missing a type parameter
+ |
+LL | fn f<B>(_: B) {}
+ | +++
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0412`.

tests/ui/cast/issue-112630.rs

@@ -0,0 +1,8 @@
+enum Foo {
+ Bar(B),
+ //~^ ERROR cannot find type `B` in this scope [E0412]
+}
+
+fn main() {
+ let _ = [0; Foo::Bar as usize];
+}

tests/ui/cast/issue-112630.stderr

@@ -0,0 +1,14 @@
+error[E0412]: cannot find type `B` in this scope
+ --> $DIR/issue-112630.rs:2:9
+ |
+LL | Bar(B),
+ | ^ not found in this scope
+ |
+help: you might be missing a type parameter
+ |
+LL | enum Foo<B> {
+ | +++
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0412`.

tests/ui/consts/issue-112824-type-mismatch-type-error-1.rs

@@ -0,0 +1,19 @@
+pub struct Opcode(pub u8);
+
+pub struct Opcode2 {
+ s: &'a S,
+ //~^ ERROR cannot find type `S` in this scope [E0412]
+ //~^^ ERROR use of undeclared lifetime name `'a` [E0261]
+}
+
+impl Opcode2 {
+ pub const OP2: Opcode2 = Opcode2 { s: Opcode(0x1) };
+}
+
+pub fn example2(msg_type: Opcode2) -> impl FnMut(&[u8]) {
+ move |i| match msg_type {
+ Opcode2::OP2 => unimplemented!(),
+ }
+}
+
+fn main() {}

tests/ui/consts/issue-112824-type-mismatch-type-error-1.stderr

@@ -0,0 +1,23 @@
+error[E0261]: use of undeclared lifetime name `'a`
+ --> $DIR/issue-112824-type-mismatch-type-error-1.rs:4:9
+ |
+LL | pub struct Opcode2 {
+ | - help: consider introducing lifetime `'a` here: `<'a>`
+LL | s: &'a S,
+ | ^^ undeclared lifetime
+
+error[E0412]: cannot find type `S` in this scope
+ --> $DIR/issue-112824-type-mismatch-type-error-1.rs:4:12
+ |
+LL | s: &'a S,
+ | ^ not found in this scope
+ |
+help: you might be missing a type parameter
+ |
+LL | pub struct Opcode2<S> {
+ | +++
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0261, E0412.
+For more information about an error, try `rustc --explain E0261`.

tests/ui/consts/issue-112824-type-mismatch-type-error.rs

@@ -0,0 +1,17 @@
+pub struct Opcode(pub u8);
+
+pub struct Opcode2(&'a S);
+//~^ ERROR cannot find type `S` in this scope [E0412]
+//~^^ ERROR use of undeclared lifetime name `'a` [E0261]
+
+impl Opcode2 {
+ pub const OP2: Opcode2 = Opcode2(Opcode(0x1));
+}
+
+pub fn example2(msg_type: Opcode2) -> impl FnMut(&[u8]) {
+ move |i| match msg_type {
+ Opcode2::OP2 => unimplemented!(),
+ }
+}
+
+fn main() {}

tests/ui/consts/issue-112824-type-mismatch-type-error.stderr

@@ -0,0 +1,23 @@
+error[E0261]: use of undeclared lifetime name `'a`
+ --> $DIR/issue-112824-type-mismatch-type-error.rs:3:21
+ |
+LL | pub struct Opcode2(&'a S);
+ | - ^^ undeclared lifetime
+ | |
+ | help: consider introducing lifetime `'a` here: `<'a>`
+
+error[E0412]: cannot find type `S` in this scope
+ --> $DIR/issue-112824-type-mismatch-type-error.rs:3:24
+ |
+LL | pub struct Opcode2(&'a S);
+ | ^ not found in this scope
+ |
+help: you might be missing a type parameter
+ |
+LL | pub struct Opcode2<S>(&'a S);
+ | +++
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0261, E0412.
+For more information about an error, try `rustc --explain E0261`.