diff options
| -rw-r--r-- | compiler/rustc_borrowck/src/type_check/mod.rs | 29 | ||||
| -rw-r--r-- | tests/ui/mir/field-projection-invariant.rs | 24 | ||||
| -rw-r--r-- | tests/ui/mir/field-projection-mutating-context.rs | 19 | ||||
| -rw-r--r-- | tests/ui/mir/field-projection-mutating-context.stderr | 12 | ||||
| -rw-r--r-- | tests/ui/mir/field-projection-mutating-context2.rs | 17 | ||||
| -rw-r--r-- | tests/ui/mir/field-projection-mutating-context2.stderr | 10 | ||||
| -rw-r--r-- | tests/ui/mir/field-ty-ascription-enums.rs | 15 | ||||
| -rw-r--r-- | tests/ui/mir/field-ty-ascription.rs | 37 |
8 files changed, 159 insertions, 4 deletions
diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs index 004b945eada..5e1334559f5 100644 --- a/compiler/rustc_borrowck/src/type_check/mod.rs +++ b/compiler/rustc_borrowck/src/type_check/mod.rs @@ -534,7 +534,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> { return PlaceTy::from_ty(self.tcx().ty_error()); } } - place_ty = self.sanitize_projection(place_ty, elem, place, location); + place_ty = self.sanitize_projection(place_ty, elem, place, location, context); } if let PlaceContext::NonMutatingUse(NonMutatingUseContext::Copy) = context { @@ -630,12 +630,14 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> { } } + #[instrument(skip(self), level = "debug")] fn sanitize_projection( &mut self, base: PlaceTy<'tcx>, pi: PlaceElem<'tcx>, place: &Place<'tcx>, location: Location, + context: PlaceContext, ) -> PlaceTy<'tcx> { debug!("sanitize_projection: {:?} {:?} {:?}", base, pi, place); let tcx = self.tcx(); @@ -713,8 +715,11 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> { match self.field_ty(place, base, field, location) { Ok(ty) => { let ty = self.cx.normalize(ty, location); - if let Err(terr) = self.cx.eq_types( + debug!(?fty, ?ty); + + if let Err(terr) = self.cx.relate_types( ty, + self.get_ambient_variance(context), fty, location.to_locations(), ConstraintCategory::Boring, @@ -743,9 +748,10 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> { let ty = self.sanitize_type(place, ty); let ty = self.cx.normalize(ty, location); self.cx - .eq_types( - base.ty, + .relate_types( ty, + self.get_ambient_variance(context), + base.ty, location.to_locations(), ConstraintCategory::TypeAnnotation, ) @@ -760,6 +766,21 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> { self.tcx().ty_error() } + fn get_ambient_variance(&self, context: PlaceContext) -> ty::Variance { + use rustc_middle::mir::visit::NonMutatingUseContext::*; + use rustc_middle::mir::visit::NonUseContext::*; + + match context { + PlaceContext::MutatingUse(_) => ty::Invariant, + PlaceContext::NonUse(StorageDead | StorageLive | VarDebugInfo) => ty::Invariant, + PlaceContext::NonMutatingUse( + Inspect | Copy | Move | SharedBorrow | ShallowBorrow | UniqueBorrow | AddressOf + | Projection, + ) => ty::Covariant, + PlaceContext::NonUse(AscribeUserTy) => ty::Covariant, + } + } + fn field_ty( &mut self, parent: &dyn fmt::Debug, diff --git a/tests/ui/mir/field-projection-invariant.rs b/tests/ui/mir/field-projection-invariant.rs new file mode 100644 index 00000000000..b5d6add043c --- /dev/null +++ b/tests/ui/mir/field-projection-invariant.rs @@ -0,0 +1,24 @@ +// build-pass +struct Inv<'a>(&'a mut &'a ()); +enum Foo<T> { + Bar, + Var(T), +} +type Supertype = Foo<for<'a> fn(Inv<'a>, Inv<'a>)>; + +fn foo(x: Foo<for<'a, 'b> fn(Inv<'a>, Inv<'b>)>) { + match x { + Supertype::Bar => {} + Supertype::Var(x) => {} + } +} + +fn foo_nested(x: Foo<Foo<for<'a, 'b> fn(Inv<'a>, Inv<'b>)>>) { + match x { + Foo::Bar => {} + Foo::Var(Supertype::Bar) => {} + Foo::Var(Supertype::Var(x)) => {} + } +} + +fn main() {} diff --git a/tests/ui/mir/field-projection-mutating-context.rs b/tests/ui/mir/field-projection-mutating-context.rs new file mode 100644 index 00000000000..a1002c088dc --- /dev/null +++ b/tests/ui/mir/field-projection-mutating-context.rs @@ -0,0 +1,19 @@ +use std::sync::Mutex; + +static GLOBAL: Mutex<&'static str> = Mutex::new("global str"); + +struct Foo<T>(T); // `T` is covariant. + +fn foo() { + let mut x: Foo<for<'a> fn(&'a str)> = Foo(|_| ()); + let Foo(ref mut y): Foo<fn(&'static str)> = x; + //~^ ERROR mismatched types + *y = |s| *GLOBAL.lock().unwrap() = s; + let string = String::from("i am shortlived"); + (x.0)(&string); +} + +fn main() { + foo(); + println!("{}", GLOBAL.lock().unwrap()); +} diff --git a/tests/ui/mir/field-projection-mutating-context.stderr b/tests/ui/mir/field-projection-mutating-context.stderr new file mode 100644 index 00000000000..9b18b3427ad --- /dev/null +++ b/tests/ui/mir/field-projection-mutating-context.stderr @@ -0,0 +1,12 @@ +error[E0308]: mismatched types + --> $DIR/field-projection-mutating-context.rs:9:13 + | +LL | let Foo(ref mut y): Foo<fn(&'static str)> = x; + | ^^^^^^^^^ one type is more general than the other + | + = note: expected fn pointer `for<'a> fn(&'a str)` + found fn pointer `fn(&str)` + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0308`. diff --git a/tests/ui/mir/field-projection-mutating-context2.rs b/tests/ui/mir/field-projection-mutating-context2.rs new file mode 100644 index 00000000000..dd9c44a16d3 --- /dev/null +++ b/tests/ui/mir/field-projection-mutating-context2.rs @@ -0,0 +1,17 @@ +use std::sync::Mutex; + +static GLOBAL: Mutex<&'static str> = Mutex::new("global str"); + +struct Foo<T>(T); // `T` is covariant. + +fn foo<'a>(mut x: Foo<fn(&'a str)>, string: &'a str) { + let Foo(ref mut y): Foo<fn(&'static str)> = x; + //~^ ERROR lifetime may not live long enough + *y = |s| *GLOBAL.lock().unwrap() = s; + (x.0)(&string); +} + +fn main() { + foo(Foo(|_| ()), &String::from("i am shortlived")); + println!("{}", GLOBAL.lock().unwrap()); +} diff --git a/tests/ui/mir/field-projection-mutating-context2.stderr b/tests/ui/mir/field-projection-mutating-context2.stderr new file mode 100644 index 00000000000..a7b66fe10ce --- /dev/null +++ b/tests/ui/mir/field-projection-mutating-context2.stderr @@ -0,0 +1,10 @@ +error: lifetime may not live long enough + --> $DIR/field-projection-mutating-context2.rs:8:25 + | +LL | fn foo<'a>(mut x: Foo<fn(&'a str)>, string: &'a str) { + | -- lifetime `'a` defined here +LL | let Foo(ref mut y): Foo<fn(&'static str)> = x; + | ^^^^^^^^^^^^^^^^^^^^^ type annotation requires that `'a` must outlive `'static` + +error: aborting due to previous error + diff --git a/tests/ui/mir/field-ty-ascription-enums.rs b/tests/ui/mir/field-ty-ascription-enums.rs new file mode 100644 index 00000000000..179af617090 --- /dev/null +++ b/tests/ui/mir/field-ty-ascription-enums.rs @@ -0,0 +1,15 @@ +// build-pass + +enum Foo<T> { + Var(T), +} // `T` is covariant. + +fn foo<'b>(x: Foo<for<'a> fn(&'a ())>) { + let Foo::Var(x): Foo<fn(&'b ())> = x; +} + +fn foo_nested<'b>(x: Foo<Foo<for<'a> fn(&'a ())>>) { + let Foo::Var(Foo::Var(x)): Foo<Foo<fn(&'b ())>> = x; +} + +fn main() {} diff --git a/tests/ui/mir/field-ty-ascription.rs b/tests/ui/mir/field-ty-ascription.rs new file mode 100644 index 00000000000..178c7916bc5 --- /dev/null +++ b/tests/ui/mir/field-ty-ascription.rs @@ -0,0 +1,37 @@ +// build-pass + +struct Foo<T>(T); // `T` is covariant. + +struct Bar<T> { + x: T, +} // `T` is covariant. + +fn bar<'b>(x: Bar<for<'a> fn(&'a ())>) { + let Bar { x }: Bar<fn(&'b ())> = x; +} + +fn bar_nested<'b>(x: Bar<Bar<for<'a> fn(&'a ())>>) { + let Bar { x: Bar { x } }: Bar<Bar<fn(&'b ())>> = x; +} + +fn bar_foo_nested<'b>(x: Bar<Foo<for<'a> fn(&'a ())>>) { + let Bar { x: Foo ( x ) }: Bar<Foo<fn(&'b ())>> = x; +} + +fn foo<'b>(x: Foo<for<'a> fn(&'a ())>) { + let Foo(y): Foo<fn(&'b ())> = x; +} + +fn foo_nested<'b>(x: Foo<Foo<for<'a> fn(&'a ())>>) { + let Foo(Foo(y)): Foo<Foo<fn(&'b ())>> = x; +} + +fn tuple<'b>(x: (u32, for<'a> fn(&'a ()))) { + let (_, y): (u32, fn(&'b ())) = x; +} + +fn tuple_nested<'b>(x: (u32, (u32, for<'a> fn(&'a ())))) { + let (_, (_, y)): (u32, (u32, fn(&'b ()))) = x; +} + +fn main() {} |