From 8f1fff04a72f65bc991b0c76b7b7300384b0d33d Mon Sep 17 00:00:00 2001 From: ouz-a Date: Tue, 31 May 2022 21:34:04 +0300 Subject: [PATCH] get_vtable returns opt instd of unwrpping --- .../rustc_trait_selection/src/traits/util.rs | 14 +++-- compiler/rustc_ty_utils/src/instance.rs | 14 +++-- src/test/ui/traits/vtable/issue-97381.rs | 30 ++++++++++ src/test/ui/traits/vtable/issue-97381.stderr | 15 +++++ src/test/ui/type/type-unsatisfiable.rs | 59 +++++++++++++++++++ .../ui/type/type-unsatisfiable.usage.stderr | 11 ++++ 6 files changed, 132 insertions(+), 11 deletions(-) create mode 100644 src/test/ui/traits/vtable/issue-97381.rs create mode 100644 src/test/ui/traits/vtable/issue-97381.stderr create mode 100644 src/test/ui/type/type-unsatisfiable.rs create mode 100644 src/test/ui/type/type-unsatisfiable.usage.stderr diff --git a/compiler/rustc_trait_selection/src/traits/util.rs b/compiler/rustc_trait_selection/src/traits/util.rs index f2e31c068a0..3a00c41d90a 100644 --- a/compiler/rustc_trait_selection/src/traits/util.rs +++ b/compiler/rustc_trait_selection/src/traits/util.rs @@ -304,22 +304,24 @@ pub fn get_vtable_index_of_object_method<'tcx, N>( tcx: TyCtxt<'tcx>, object: &super::ImplSourceObjectData<'tcx, N>, method_def_id: DefId, -) -> usize { +) -> Option { let existential_trait_ref = object .upcast_trait_ref .map_bound(|trait_ref| ty::ExistentialTraitRef::erase_self_ty(tcx, trait_ref)); let existential_trait_ref = tcx.erase_regions(existential_trait_ref); + // Count number of methods preceding the one we are selecting and // add them to the total offset. - let index = tcx + if let Some(index) = tcx .own_existential_vtable_entries(existential_trait_ref) .iter() .copied() .position(|def_id| def_id == method_def_id) - .unwrap_or_else(|| { - bug!("get_vtable_index_of_object_method: {:?} was not found", method_def_id); - }); - object.vtable_base + index + { + Some(object.vtable_base + index) + } else { + None + } } pub fn closure_trait_ref_and_return_type<'tcx>( diff --git a/compiler/rustc_ty_utils/src/instance.rs b/compiler/rustc_ty_utils/src/instance.rs index 17eac2bb2c9..c78a5855edb 100644 --- a/compiler/rustc_ty_utils/src/instance.rs +++ b/compiler/rustc_ty_utils/src/instance.rs @@ -347,11 +347,15 @@ fn resolve_associated_item<'tcx>( _ => None, }, traits::ImplSource::Object(ref data) => { - let index = traits::get_vtable_index_of_object_method(tcx, data, trait_item_id); - Some(Instance { - def: ty::InstanceDef::Virtual(trait_item_id, index), - substs: rcvr_substs, - }) + if let Some(index) = traits::get_vtable_index_of_object_method(tcx, data, trait_item_id) + { + Some(Instance { + def: ty::InstanceDef::Virtual(trait_item_id, index), + substs: rcvr_substs, + }) + } else { + None + } } traits::ImplSource::Builtin(..) => { if Some(trait_ref.def_id) == tcx.lang_items().clone_trait() { diff --git a/src/test/ui/traits/vtable/issue-97381.rs b/src/test/ui/traits/vtable/issue-97381.rs new file mode 100644 index 00000000000..393cf91efc2 --- /dev/null +++ b/src/test/ui/traits/vtable/issue-97381.rs @@ -0,0 +1,30 @@ +use std::ops::Deref; +trait MyTrait: Deref {} +struct MyStruct(u32); +impl MyTrait for MyStruct {} +impl Deref for MyStruct { + type Target = u32; + + fn deref(&self) -> &Self::Target { + &self.0 + } +} +fn get_concrete_value(i: u32) -> MyStruct { + MyStruct(i) +} +fn get_boxed_value(i: u32) -> Box { + Box::new(get_concrete_value(i)) +} +fn main() { + let v = [1, 2, 3] + .iter() + .map(|i| get_boxed_value(*i)) + .collect::>(); + + let el = &v[0]; + + for _ in v { + //~^ ERROR cannot move out of `v` because it is borrowed + println!("{}", ***el > 0); + } +} diff --git a/src/test/ui/traits/vtable/issue-97381.stderr b/src/test/ui/traits/vtable/issue-97381.stderr new file mode 100644 index 00000000000..f88c8716ff7 --- /dev/null +++ b/src/test/ui/traits/vtable/issue-97381.stderr @@ -0,0 +1,15 @@ +error[E0505]: cannot move out of `v` because it is borrowed + --> $DIR/issue-97381.rs:26:14 + | +LL | let el = &v[0]; + | - borrow of `v` occurs here +LL | +LL | for _ in v { + | ^ move out of `v` occurs here +LL | +LL | println!("{}", ***el > 0); + | ---- borrow later used here + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0505`. diff --git a/src/test/ui/type/type-unsatisfiable.rs b/src/test/ui/type/type-unsatisfiable.rs new file mode 100644 index 00000000000..7fbbb50dc11 --- /dev/null +++ b/src/test/ui/type/type-unsatisfiable.rs @@ -0,0 +1,59 @@ +// revisions: lib usage +//[lib] compile-flags: --crate-type=lib +//[lib] build-pass + +use std::ops::Sub; +trait Vector2 { + type ScalarType; + + fn from_values(x: Self::ScalarType, y: Self::ScalarType) -> Self + where + Self: Sized; + + fn x(&self) -> Self::ScalarType; + fn y(&self) -> Self::ScalarType; +} + +impl Sub for dyn Vector2 +where + T: Sub, + (dyn Vector2): Sized, +{ + type Output = dyn Vector2; + + fn sub(self, rhs: Self) -> Self::Output { + Self::from_values(self.x() - rhs.x(), self.y() - rhs.y()) + } +} + +struct Vec2 { + x: i32, + y: i32, +} + +impl Vector2 for Vec2 { + type ScalarType = i32; + + fn from_values(x: Self::ScalarType, y: Self::ScalarType) -> Self + where + Self: Sized, + { + Self { x, y } + } + + fn x(&self) -> Self::ScalarType { + self.x + } + fn y(&self) -> Self::ScalarType { + self.y + } +} + +#[cfg(usage)] +fn main() { + let hey: Box> = Box::new(Vec2 { x: 1, y: 2 }); + let word: Box> = Box::new(Vec2 { x: 1, y: 2 }); + + let bar = *hey - *word; + //[usage]~^ ERROR cannot subtract +} diff --git a/src/test/ui/type/type-unsatisfiable.usage.stderr b/src/test/ui/type/type-unsatisfiable.usage.stderr new file mode 100644 index 00000000000..56e2e30afac --- /dev/null +++ b/src/test/ui/type/type-unsatisfiable.usage.stderr @@ -0,0 +1,11 @@ +error[E0369]: cannot subtract `(dyn Vector2 + 'static)` from `dyn Vector2` + --> $DIR/type-unsatisfiable.rs:57:20 + | +LL | let bar = *hey - *word; + | ---- ^ ----- (dyn Vector2 + 'static) + | | + | dyn Vector2 + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0369`.