diff --git a/src/librustc/hir/lowering.rs b/src/librustc/hir/lowering.rs
index 6b6032516ca73..e665e058e6022 100644
--- a/src/librustc/hir/lowering.rs
+++ b/src/librustc/hir/lowering.rs
@@ -1874,15 +1874,16 @@ impl<'a> LoweringContext<'a> {
if let Ok(snippet) = self.sess.source_map().span_to_snippet(data.span) {
// Do not suggest going from `Trait()` to `Trait<>`
if data.inputs.len() > 0 {
- let split = snippet.find('(').unwrap();
- let trait_name = &snippet[0..split];
- let args = &snippet[split + 1 .. snippet.len() - 1];
- err.span_suggestion(
- data.span,
- "use angle brackets instead",
- format!("{}<{}>", trait_name, args),
- Applicability::MaybeIncorrect,
- );
+ if let Some(split) = snippet.find('(') {
+ let trait_name = &snippet[0..split];
+ let args = &snippet[split + 1 .. snippet.len() - 1];
+ err.span_suggestion(
+ data.span,
+ "use angle brackets instead",
+ format!("{}<{}>", trait_name, args),
+ Applicability::MaybeIncorrect,
+ );
+ }
}
};
err.emit();
diff --git a/src/librustc_mir/build/matches/simplify.rs b/src/librustc_mir/build/matches/simplify.rs
index 9b7bccca2ddf3..3e71b871801d1 100644
--- a/src/librustc_mir/build/matches/simplify.rs
+++ b/src/librustc_mir/build/matches/simplify.rs
@@ -164,7 +164,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
self.hir.tcx().features().exhaustive_patterns &&
!v.uninhabited_from(self.hir.tcx(), substs, adt_def.adt_kind()).is_empty()
}
- });
+ }) && (adt_def.did.is_local() || !adt_def.is_variant_list_non_exhaustive());
if irrefutable {
let place = tcx.mk_place_downcast(match_pair.place, adt_def, variant_index);
candidate.match_pairs.extend(self.field_match_pairs(place, subpatterns));
diff --git a/src/librustc_mir/transform/const_prop.rs b/src/librustc_mir/transform/const_prop.rs
index e7095101f465d..272369008370a 100644
--- a/src/librustc_mir/transform/const_prop.rs
+++ b/src/librustc_mir/transform/const_prop.rs
@@ -22,7 +22,7 @@ use rustc::ty::subst::InternalSubsts;
use rustc_data_structures::fx::FxHashMap;
use rustc_index::vec::IndexVec;
use rustc::ty::layout::{
- LayoutOf, TyLayout, LayoutError, HasTyCtxt, TargetDataLayout, HasDataLayout,
+ LayoutOf, TyLayout, LayoutError, HasTyCtxt, TargetDataLayout, HasDataLayout, Size,
};
use crate::interpret::{
@@ -34,6 +34,9 @@ use crate::interpret::{
use crate::const_eval::error_to_const_error;
use crate::transform::{MirPass, MirSource};
+/// The maximum number of bytes that we'll allocate space for a return value.
+const MAX_ALLOC_LIMIT: u64 = 1024;
+
pub struct ConstProp;
impl<'tcx> MirPass<'tcx> for ConstProp {
@@ -434,6 +437,11 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
) -> Option<()> {
let span = source_info.span;
+ // #66397: Don't try to eval into large places as that can cause an OOM
+ if place_layout.size >= Size::from_bytes(MAX_ALLOC_LIMIT) {
+ return None;
+ }
+
let overflow_check = self.tcx.sess.overflow_checks();
// Perform any special handling for specific Rvalue types.
diff --git a/src/librustc_target/abi/mod.rs b/src/librustc_target/abi/mod.rs
index fde5c5bed4d91..26d37f196befa 100644
--- a/src/librustc_target/abi/mod.rs
+++ b/src/librustc_target/abi/mod.rs
@@ -738,11 +738,7 @@ impl FieldPlacement {
pub fn offset(&self, i: usize) -> Size {
match *self {
- FieldPlacement::Union(count) => {
- assert!(i < count,
- "Tried to access field {} of union with {} fields", i, count);
- Size::ZERO
- },
+ FieldPlacement::Union(_) => Size::ZERO,
FieldPlacement::Array { stride, count } => {
let i = i as u64;
assert!(i < count);
diff --git a/src/librustc_typeck/astconv.rs b/src/librustc_typeck/astconv.rs
index aa05a08686a99..e1b540515af41 100644
--- a/src/librustc_typeck/astconv.rs
+++ b/src/librustc_typeck/astconv.rs
@@ -1221,16 +1221,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
)
}
- /// Transform a `PolyTraitRef` into a `PolyExistentialTraitRef` by
- /// removing the dummy `Self` type (`trait_object_dummy_self`).
- fn trait_ref_to_existential(&self, trait_ref: ty::TraitRef<'tcx>)
- -> ty::ExistentialTraitRef<'tcx> {
- if trait_ref.self_ty() != self.tcx().types.trait_object_dummy_self {
- bug!("trait_ref_to_existential called on {:?} with non-dummy Self", trait_ref);
- }
- ty::ExistentialTraitRef::erase_self_ty(self.tcx(), trait_ref)
- }
-
fn conv_object_ty_poly_trait_ref(&self,
span: Span,
trait_bounds: &[hir::PolyTraitRef],
@@ -1412,13 +1402,30 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
debug!("regular_traits: {:?}", regular_traits);
debug!("auto_traits: {:?}", auto_traits);
+ // Transform a `PolyTraitRef` into a `PolyExistentialTraitRef` by
+ // removing the dummy `Self` type (`trait_object_dummy_self`).
+ let trait_ref_to_existential = |trait_ref: ty::TraitRef<'tcx>| {
+ if trait_ref.self_ty() != dummy_self {
+ // FIXME: There appears to be a missing filter on top of `expand_trait_aliases`,
+ // which picks up non-supertraits where clauses - but also, the object safety
+ // completely ignores trait aliases, which could be object safety hazards. We
+ // `delay_span_bug` here to avoid an ICE in stable even when the feature is
+ // disabled. (#66420)
+ tcx.sess.delay_span_bug(DUMMY_SP, &format!(
+ "trait_ref_to_existential called on {:?} with non-dummy Self",
+ trait_ref,
+ ));
+ }
+ ty::ExistentialTraitRef::erase_self_ty(tcx, trait_ref)
+ };
+
// Erase the `dummy_self` (`trait_object_dummy_self`) used above.
let existential_trait_refs = regular_traits.iter().map(|i| {
- i.trait_ref().map_bound(|trait_ref| self.trait_ref_to_existential(trait_ref))
+ i.trait_ref().map_bound(|trait_ref| trait_ref_to_existential(trait_ref))
});
let existential_projections = bounds.projection_bounds.iter().map(|(bound, _)| {
bound.map_bound(|b| {
- let trait_ref = self.trait_ref_to_existential(b.projection_ty.trait_ref(tcx));
+ let trait_ref = trait_ref_to_existential(b.projection_ty.trait_ref(tcx));
ty::ExistentialProjection {
ty: b.ty,
item_def_id: b.projection_ty.item_def_id,
diff --git a/src/librustc_typeck/check/generator_interior.rs b/src/librustc_typeck/check/generator_interior.rs
index ff9c945eec452..6e37c0dbbdf9d 100644
--- a/src/librustc_typeck/check/generator_interior.rs
+++ b/src/librustc_typeck/check/generator_interior.rs
@@ -244,7 +244,13 @@ impl<'a, 'tcx> Visitor<'tcx> for InteriorVisitor<'a, 'tcx> {
// can be reborrowed without needing to spill to a temporary.
// If this were not the case, then we could conceivably have
// to create intermediate temporaries.)
- let ty = self.fcx.tables.borrow().expr_ty(expr);
- self.record(ty, scope, Some(expr), expr.span);
+ //
+ // The type table might not have information for this expression
+ // if it is in a malformed scope. (#66387)
+ if let Some(ty) = self.fcx.tables.borrow().expr_ty_opt(expr) {
+ self.record(ty, scope, Some(expr), expr.span);
+ } else {
+ self.fcx.tcx.sess.delay_span_bug(expr.span, "no type for node");
+ }
}
}
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index f7132cd868aac..a02d5b5a571c5 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -3010,7 +3010,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
fallback_has_occurred: bool,
mutate_fullfillment_errors: impl Fn(&mut Vec<traits::FulfillmentError<'tcx>>),
) {
- if let Err(mut errors) = self.fulfillment_cx.borrow_mut().select_where_possible(self) {
+ let result = self.fulfillment_cx.borrow_mut().select_where_possible(self);
+ if let Err(mut errors) = result {
mutate_fullfillment_errors(&mut errors);
self.report_fulfillment_errors(&errors, self.inh.body_id, fallback_has_occurred);
}
diff --git a/src/libsyntax/attr/builtin.rs b/src/libsyntax/attr/builtin.rs
index 84c86c9651fcf..5217f63660795 100644
--- a/src/libsyntax/attr/builtin.rs
+++ b/src/libsyntax/attr/builtin.rs
@@ -655,7 +655,10 @@ fn find_deprecation_generic<'a, I>(sess: &ParseSess,
break
}
- let meta = attr.meta().unwrap();
+ let meta = match attr.meta() {
+ Some(meta) => meta,
+ None => continue,
+ };
depr = match &meta.kind {
MetaItemKind::Word => Some(Deprecation { since: None, note: None }),
MetaItemKind::NameValue(..) => {
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index e81d4573b73e5..e6e9d37962af4 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -442,7 +442,9 @@ impl<'a> Parser<'a> {
crate fn unexpected<T>(&mut self) -> PResult<'a, T> {
match self.expect_one_of(&[], &[]) {
Err(e) => Err(e),
- Ok(_) => unreachable!(),
+ // We can get `Ok(true)` from `recover_closing_delimiter`
+ // which is called in `expected_one_of_not_found`.
+ Ok(_) => FatalError.raise(),
}
}
diff --git a/src/libsyntax_ext/format.rs b/src/libsyntax_ext/format.rs
index 37310f46f7eed..3c7f80aa399bf 100644
--- a/src/libsyntax_ext/format.rs
+++ b/src/libsyntax_ext/format.rs
@@ -374,10 +374,12 @@ impl<'a, 'b> Context<'a, 'b> {
format!("are {} arguments", count)
},
));
- e.span_label(
- self.args[pos].span,
- "this parameter corresponds to the precision flag",
- );
+ if let Some(arg) = self.args.get(pos) {
+ e.span_label(
+ arg.span,
+ "this parameter corresponds to the precision flag",
+ );
+ }
zero_based_note = true;
}
_ => {}
diff --git a/src/test/ui/async-await/issue-66387-if-without-else.rs b/src/test/ui/async-await/issue-66387-if-without-else.rs
new file mode 100644
index 0000000000000..aa5a8db61210d
--- /dev/null
+++ b/src/test/ui/async-await/issue-66387-if-without-else.rs
@@ -0,0 +1,10 @@
+// edition:2018
+async fn f() -> i32 {
+ if true { //~ ERROR if may be missing an else clause
+ return 0;
+ }
+ // An `if` block without `else` causes the type table not to have a type for this expr.
+ // Check that we do not unconditionally access the type table and we don't ICE.
+}
+
+fn main() {}
diff --git a/src/test/ui/async-await/issue-66387-if-without-else.stderr b/src/test/ui/async-await/issue-66387-if-without-else.stderr
new file mode 100644
index 0000000000000..32952059525a0
--- /dev/null
+++ b/src/test/ui/async-await/issue-66387-if-without-else.stderr
@@ -0,0 +1,16 @@
+error[E0317]: if may be missing an else clause
+ --> $DIR/issue-66387-if-without-else.rs:3:5
+ |
+LL | / if true {
+LL | | return 0;
+LL | | }
+ | |_____^ expected (), found i32
+ |
+ = note: expected type `()`
+ found type `i32`
+ = note: `if` expressions without `else` evaluate to `()`
+ = help: consider adding an `else` block that evaluates to the expected type
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0317`.
diff --git a/src/test/ui/consts/issue-66342.rs b/src/test/ui/consts/issue-66342.rs
new file mode 100644
index 0000000000000..417f69041658d
--- /dev/null
+++ b/src/test/ui/consts/issue-66342.rs
@@ -0,0 +1,12 @@
+// check-pass
+// only-x86_64
+
+// Checks that the compiler does not actually try to allocate 4 TB during compilation and OOM crash.
+
+fn foo() -> [u8; 4 * 1024 * 1024 * 1024 * 1024] {
+ unimplemented!()
+}
+
+fn main() {
+ foo();
+}
diff --git a/src/test/ui/consts/issue-66397.rs b/src/test/ui/consts/issue-66397.rs
new file mode 100644
index 0000000000000..1b4aff43b5bf1
--- /dev/null
+++ b/src/test/ui/consts/issue-66397.rs
@@ -0,0 +1,8 @@
+// check-pass
+// only-x86_64
+
+// Checks that the compiler does not actually try to allocate 4 TB during compilation and OOM crash.
+
+fn main() {
+ [0; 4 * 1024 * 1024 * 1024 * 1024];
+}
diff --git a/src/test/ui/deprecation/issue-66340-deprecated-attr-non-meta-grammar.rs b/src/test/ui/deprecation/issue-66340-deprecated-attr-non-meta-grammar.rs
new file mode 100644
index 0000000000000..c0cde75d4caeb
--- /dev/null
+++ b/src/test/ui/deprecation/issue-66340-deprecated-attr-non-meta-grammar.rs
@@ -0,0 +1,11 @@
+// The original problem in #66340 was that `find_deprecation_generic`
+// called `attr.meta().unwrap()` under the assumption that the attribute
+// was a well-formed `MetaItem`.
+
+fn main() {
+ foo()
+}
+
+#[deprecated(note = test)]
+//~^ ERROR expected unsuffixed literal or identifier, found `test`
+fn foo() {}
diff --git a/src/test/ui/deprecation/issue-66340-deprecated-attr-non-meta-grammar.stderr b/src/test/ui/deprecation/issue-66340-deprecated-attr-non-meta-grammar.stderr
new file mode 100644
index 0000000000000..24178faf8de78
--- /dev/null
+++ b/src/test/ui/deprecation/issue-66340-deprecated-attr-non-meta-grammar.stderr
@@ -0,0 +1,8 @@
+error: expected unsuffixed literal or identifier, found `test`
+ --> $DIR/issue-66340-deprecated-attr-non-meta-grammar.rs:9:21
+ |
+LL | #[deprecated(note = test)]
+ | ^^^^
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/if/ifmt-bad-arg.rs b/src/test/ui/if/ifmt-bad-arg.rs
index ba897f171af25..a0b0a8fb98594 100644
--- a/src/test/ui/if/ifmt-bad-arg.rs
+++ b/src/test/ui/if/ifmt-bad-arg.rs
@@ -86,4 +86,9 @@ tenth number: {}",
println!("{:foo}", 1); //~ ERROR unknown format trait `foo`
println!("{5} {:4$} {6:7$}", 1);
//~^ ERROR invalid reference to positional arguments 4, 5, 6 and 7 (there is 1 argument)
+
+ // We used to ICE here because we tried to unconditionally access the first argument, which
+ // doesn't exist.
+ println!("{:.*}");
+ //~^ ERROR 2 positional arguments in format string, but no arguments were given
}
diff --git a/src/test/ui/if/ifmt-bad-arg.stderr b/src/test/ui/if/ifmt-bad-arg.stderr
index c58cbc312335a..11dcc3a6d232e 100644
--- a/src/test/ui/if/ifmt-bad-arg.stderr
+++ b/src/test/ui/if/ifmt-bad-arg.stderr
@@ -285,6 +285,17 @@ LL | println!("{5} {:4$} {6:7$}", 1);
= note: positional arguments are zero-based
= note: for information about formatting flags, visit https://doc.rust-lang.org/std/fmt/index.html
+error: 2 positional arguments in format string, but no arguments were given
+ --> $DIR/ifmt-bad-arg.rs:92:15
+ |
+LL | println!("{:.*}");
+ | ^^--^
+ | |
+ | this precision flag adds an extra required argument at position 0, which is why there are 2 arguments expected
+ |
+ = note: positional arguments are zero-based
+ = note: for information about formatting flags, visit https://doc.rust-lang.org/std/fmt/index.html
+
error[E0308]: mismatched types
--> $DIR/ifmt-bad-arg.rs:78:32
|
@@ -303,6 +314,6 @@ LL | println!("{} {:07$.*} {}", 1, 3.2, 4);
= note: expected type `&usize`
found type `&{float}`
-error: aborting due to 35 previous errors
+error: aborting due to 36 previous errors
For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/issues/issue-65462.rs b/src/test/ui/issues/issue-65462.rs
new file mode 100644
index 0000000000000..8c39ea531d244
--- /dev/null
+++ b/src/test/ui/issues/issue-65462.rs
@@ -0,0 +1,15 @@
+// build-pass
+
+enum Empty {}
+enum Enum {
+ Empty( Empty )
+}
+
+fn foobar() -> Option< Enum > {
+ let value: Option< Empty > = None;
+ Some( Enum::Empty( value? ) )
+}
+
+fn main() {
+ foobar();
+}
diff --git a/src/test/ui/issues/issue-65673.rs b/src/test/ui/issues/issue-65673.rs
new file mode 100644
index 0000000000000..4b47bd493a568
--- /dev/null
+++ b/src/test/ui/issues/issue-65673.rs
@@ -0,0 +1,12 @@
+#![feature(trait_alias)] // Enabled to reduce stderr output, but can be triggered even if disabled.
+trait Trait {}
+trait WithType {
+ type Ctx;
+}
+trait Alias<T> = where T: Trait;
+
+impl<T> WithType for T {
+ type Ctx = dyn Alias<T>;
+//~^ ERROR the size for values of type `(dyn Trait + 'static)` cannot be known at compilation time
+}
+fn main() {}
diff --git a/src/test/ui/issues/issue-65673.stderr b/src/test/ui/issues/issue-65673.stderr
new file mode 100644
index 0000000000000..a556e35b6a944
--- /dev/null
+++ b/src/test/ui/issues/issue-65673.stderr
@@ -0,0 +1,17 @@
+error[E0277]: the size for values of type `(dyn Trait + 'static)` cannot be known at compilation time
+ --> $DIR/issue-65673.rs:9:5
+ |
+LL | type Ctx;
+ | --- associated type defined here
+...
+LL | impl<T> WithType for T {
+ | ---------------------- in this `impl` item
+LL | type Ctx = dyn Alias<T>;
+ | ^^^^^^^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
+ |
+ = help: the trait `std::marker::Sized` is not implemented for `(dyn Trait + 'static)`
+ = note: to learn more, visit <https://doc.rust-lang.org/book/ch19-04-advanced-types.html#dynamically-sized-types-and-the-sized-trait>
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/issues/issue-66353.rs b/src/test/ui/issues/issue-66353.rs
new file mode 100644
index 0000000000000..d8abdd5206ef4
--- /dev/null
+++ b/src/test/ui/issues/issue-66353.rs
@@ -0,0 +1,15 @@
+// #66353: ICE when trying to recover from incorrect associated type
+
+trait _Func<T> {
+ fn func(_: Self);
+}
+
+trait _A {
+ type AssocT;
+}
+
+fn main() {
+ _Func::< <() as _A>::AssocT >::func(());
+ //~^ ERROR the trait bound `(): _A` is not satisfied
+ //~| ERROR the trait bound `(): _Func<_>` is not satisfied
+}
diff --git a/src/test/ui/issues/issue-66353.stderr b/src/test/ui/issues/issue-66353.stderr
new file mode 100644
index 0000000000000..8fd50300ca63e
--- /dev/null
+++ b/src/test/ui/issues/issue-66353.stderr
@@ -0,0 +1,18 @@
+error[E0277]: the trait bound `(): _A` is not satisfied
+ --> $DIR/issue-66353.rs:12:14
+ |
+LL | _Func::< <() as _A>::AssocT >::func(());
+ | ^^^^^^^^^^^^^^^^^^ the trait `_A` is not implemented for `()`
+
+error[E0277]: the trait bound `(): _Func<_>` is not satisfied
+ --> $DIR/issue-66353.rs:12:41
+ |
+LL | fn func(_: Self);
+ | ----------------- required by `_Func::func`
+...
+LL | _Func::< <() as _A>::AssocT >::func(());
+ | ^^ the trait `_Func<_>` is not implemented for `()`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/parser/issue-66357-unexpected-unreachable.rs b/src/test/ui/parser/issue-66357-unexpected-unreachable.rs
new file mode 100644
index 0000000000000..1730adfa91419
--- /dev/null
+++ b/src/test/ui/parser/issue-66357-unexpected-unreachable.rs
@@ -0,0 +1,14 @@
+// The problem in #66357 was that the call trace:
+//
+// - parse_fn_block_decl
+// - expect_or
+// - unexpected
+// - expect_one_of
+// - expected_one_of_not_found
+// - recover_closing_delimiter
+//
+// ended up bubbling up `Ok(true)` to `unexpected` which then used `unreachable!()`.
+
+fn f() { |[](* }
+//~^ ERROR expected one of `,` or `:`, found `(`
+//~| ERROR expected one of `)`, `-`, `_`, `box`, `mut`, `ref`, `|`, identifier, or path, found `*`
diff --git a/src/test/ui/parser/issue-66357-unexpected-unreachable.stderr b/src/test/ui/parser/issue-66357-unexpected-unreachable.stderr
new file mode 100644
index 0000000000000..c7b6e15ddace8
--- /dev/null
+++ b/src/test/ui/parser/issue-66357-unexpected-unreachable.stderr
@@ -0,0 +1,16 @@
+error: expected one of `,` or `:`, found `(`
+ --> $DIR/issue-66357-unexpected-unreachable.rs:12:13
+ |
+LL | fn f() { |[](* }
+ | ^ expected one of `,` or `:` here
+
+error: expected one of `)`, `-`, `_`, `box`, `mut`, `ref`, `|`, identifier, or path, found `*`
+ --> $DIR/issue-66357-unexpected-unreachable.rs:12:14
+ |
+LL | fn f() { |[](* }
+ | -^ help: `)` may belong here
+ | |
+ | unclosed delimiter
+
+error: aborting due to 2 previous errors
+
diff --git a/src/test/ui/rfc-2008-non-exhaustive/auxiliary/monovariants.rs b/src/test/ui/rfc-2008-non-exhaustive/auxiliary/monovariants.rs
new file mode 100644
index 0000000000000..5f86db86d4477
--- /dev/null
+++ b/src/test/ui/rfc-2008-non-exhaustive/auxiliary/monovariants.rs
@@ -0,0 +1,8 @@
+#[non_exhaustive]
+pub enum NonExhaustiveMonovariant {
+ Variant(u32),
+}
+
+pub enum ExhaustiveMonovariant {
+ Variant(u32),
+}
diff --git a/src/test/ui/rfc-2008-non-exhaustive/borrowck-exhaustive.rs b/src/test/ui/rfc-2008-non-exhaustive/borrowck-exhaustive.rs
new file mode 100644
index 0000000000000..be775b37f7b77
--- /dev/null
+++ b/src/test/ui/rfc-2008-non-exhaustive/borrowck-exhaustive.rs
@@ -0,0 +1,42 @@
+// Test that the borrow checker doesn't consider checking an exhaustive pattern
+// as an access.
+
+// check-pass
+
+// aux-build:monovariants.rs
+extern crate monovariants;
+
+use monovariants::ExhaustiveMonovariant;
+
+enum Local {
+ Variant(u32),
+}
+
+#[non_exhaustive]
+enum LocalNonExhaustive {
+ Variant(u32),
+}
+
+fn main() {
+ let mut x = ExhaustiveMonovariant::Variant(1);
+ let y = &mut x;
+ match x {
+ ExhaustiveMonovariant::Variant(_) => {},
+ _ => {},
+ }
+ drop(y);
+ let mut x = Local::Variant(1);
+ let y = &mut x;
+ match x {
+ Local::Variant(_) => {},
+ _ => {},
+ }
+ drop(y);
+ let mut x = LocalNonExhaustive::Variant(1);
+ let y = &mut x;
+ match x {
+ LocalNonExhaustive::Variant(_) => {},
+ _ => {},
+ }
+ drop(y);
+}
diff --git a/src/test/ui/rfc-2008-non-exhaustive/borrowck-non-exhaustive.rs b/src/test/ui/rfc-2008-non-exhaustive/borrowck-non-exhaustive.rs
new file mode 100644
index 0000000000000..00dcf89c7aa67
--- /dev/null
+++ b/src/test/ui/rfc-2008-non-exhaustive/borrowck-non-exhaustive.rs
@@ -0,0 +1,18 @@
+// Test that the borrow checker considers `#[non_exhaustive]` when checking
+// whether a match contains a discriminant read.
+
+// aux-build:monovariants.rs
+extern crate monovariants;
+
+use monovariants::NonExhaustiveMonovariant;
+
+fn main() {
+ let mut x = NonExhaustiveMonovariant::Variant(1);
+ let y = &mut x;
+ match x {
+ NonExhaustiveMonovariant::Variant(_) => {},
+ //~^ ERROR cannot use `x` because it was mutably borrowed
+ _ => {},
+ }
+ drop(y);
+}
diff --git a/src/test/ui/rfc-2008-non-exhaustive/borrowck-non-exhaustive.stderr b/src/test/ui/rfc-2008-non-exhaustive/borrowck-non-exhaustive.stderr
new file mode 100644
index 0000000000000..9edfa84cbc085
--- /dev/null
+++ b/src/test/ui/rfc-2008-non-exhaustive/borrowck-non-exhaustive.stderr
@@ -0,0 +1,15 @@
+error[E0503]: cannot use `x` because it was mutably borrowed
+ --> $DIR/borrowck-non-exhaustive.rs:13:9
+ |
+LL | let y = &mut x;
+ | ------ borrow of `x` occurs here
+LL | match x {
+LL | NonExhaustiveMonovariant::Variant(_) => {},
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ use of borrowed `x`
+...
+LL | drop(y);
+ | - borrow later used here
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0503`.