From 283ffcfce71df51f3d1da4d63441de150938cacd Mon Sep 17 00:00:00 2001 From: Matthew Jasper Date: Mon, 11 Feb 2019 21:09:47 +0000 Subject: [PATCH] Check the self-type of inherent associated constants --- src/librustc_typeck/check/mod.rs | 26 ++++++++++++------- .../user-annotations/dump-adt-brace-struct.rs | 4 ++- .../dump-adt-brace-struct.stderr | 8 +++--- .../ui/nll/user-annotations/dump-fn-method.rs | 19 ++++++++++---- .../user-annotations/dump-fn-method.stderr | 20 +++++++------- .../inherent-associated-constants.rs | 17 ++++++++++++ .../inherent-associated-constants.stderr | 10 +++++++ 7 files changed, 74 insertions(+), 30 deletions(-) create mode 100644 src/test/ui/nll/user-annotations/inherent-associated-constants.rs create mode 100644 src/test/ui/nll/user-annotations/inherent-associated-constants.stderr diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs index fb8f608812197..8d027b07188cc 100644 --- a/src/librustc_typeck/check/mod.rs +++ b/src/librustc_typeck/check/mod.rs @@ -2236,7 +2236,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> { hir_id, def_id, substs, user_self_ty, self.tag(), ); - if !substs.is_noop() { + if Self::can_contain_user_lifetime_bounds((substs, user_self_ty)) { let canonicalized = self.infcx.canonicalize_user_type_annotation( &UserType::TypeOf(def_id, UserSubsts { substs, @@ -2431,15 +2431,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> { let ty = self.to_ty(ast_ty); debug!("to_ty_saving_user_provided_ty: ty={:?}", ty); - // If the type given by the user has free regions, save it for - // later, since NLL would like to enforce those. Also pass in - // types that involve projections, since those can resolve to - // `'static` bounds (modulo #54940, which hopefully will be - // fixed by the time you see this comment, dear reader, - // although I have my doubts). Also pass in types with inference - // types, because they may be repeated. Other sorts of things - // are already sufficiently enforced with erased regions. =) - if ty.has_free_regions() || ty.has_projections() || ty.has_infer_types() { + if Self::can_contain_user_lifetime_bounds(ty) { let c_ty = self.infcx.canonicalize_response(&UserType::Ty(ty)); debug!("to_ty_saving_user_provided_ty: c_ty={:?}", c_ty); self.tables.borrow_mut().user_provided_types_mut().insert(ast_ty.hir_id, c_ty); @@ -2448,6 +2440,20 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> { ty } + // If the type given by the user has free regions, save it for later, since + // NLL would like to enforce those. Also pass in types that involve + // projections, since those can resolve to `'static` bounds (modulo #54940, + // which hopefully will be fixed by the time you see this comment, dear + // reader, although I have my doubts). Also pass in types with inference + // types, because they may be repeated. Other sorts of things are already + // sufficiently enforced with erased regions. =) + fn can_contain_user_lifetime_bounds(t: T) -> bool + where + T: TypeFoldable<'tcx> + { + t.has_free_regions() || t.has_projections() || t.has_infer_types() + } + pub fn node_ty(&self, id: hir::HirId) -> Ty<'tcx> { match self.tables.borrow().node_types().get(id) { Some(&t) => t, diff --git a/src/test/ui/nll/user-annotations/dump-adt-brace-struct.rs b/src/test/ui/nll/user-annotations/dump-adt-brace-struct.rs index 5dcd41078c787..45f56836d18b5 100644 --- a/src/test/ui/nll/user-annotations/dump-adt-brace-struct.rs +++ b/src/test/ui/nll/user-annotations/dump-adt-brace-struct.rs @@ -15,5 +15,7 @@ fn main() { SomeStruct::<_> { t: 22 }; // Nothing interesting given, no annotation. - SomeStruct:: { t: 22 }; //~ ERROR [u32] + SomeStruct:: { t: 22 }; // No lifetime bounds given. + + SomeStruct::<&'static u32> { t: &22 }; //~ ERROR [&ReStatic u32] } diff --git a/src/test/ui/nll/user-annotations/dump-adt-brace-struct.stderr b/src/test/ui/nll/user-annotations/dump-adt-brace-struct.stderr index 123c26195d006..6e24da094e0d2 100644 --- a/src/test/ui/nll/user-annotations/dump-adt-brace-struct.stderr +++ b/src/test/ui/nll/user-annotations/dump-adt-brace-struct.stderr @@ -1,8 +1,8 @@ -error: user substs: UserSubsts { substs: [u32], user_self_ty: None } - --> $DIR/dump-adt-brace-struct.rs:18:5 +error: user substs: UserSubsts { substs: [&ReStatic u32], user_self_ty: None } + --> $DIR/dump-adt-brace-struct.rs:20:5 | -LL | SomeStruct:: { t: 22 }; //~ ERROR [u32] - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ +LL | SomeStruct::<&'static u32> { t: &22 }; //~ ERROR [&ReStatic u32] + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: aborting due to previous error diff --git a/src/test/ui/nll/user-annotations/dump-fn-method.rs b/src/test/ui/nll/user-annotations/dump-fn-method.rs index 7551a9474dc08..b689f18c22593 100644 --- a/src/test/ui/nll/user-annotations/dump-fn-method.rs +++ b/src/test/ui/nll/user-annotations/dump-fn-method.rs @@ -11,7 +11,7 @@ trait Bazoom { fn method(&self, arg: T, arg2: U) { } } -impl Bazoom for T { +impl Bazoom for S { } fn foo<'a, T>(_: T) { } @@ -22,20 +22,29 @@ fn main() { let x = foo; x(22); - // Here: `u32` is given. - let x = foo::; //~ ERROR [u32] + // Here: `u32` is given, which doesn't contain any lifetimes, so we don't + // have any annotation. + let x = foo::; x(22); + let x = foo::<&'static u32>; //~ ERROR [&ReStatic u32] + x(&22); + // Here: we only want the `T` to be given, the rest should be variables. // // (`T` refers to the declaration of `Bazoom`) let x = <_ as Bazoom>::method::<_>; //~ ERROR [^0, u32, ^1] x(&22, 44, 66); - // Here: all are given - let x = >::method::; //~ ERROR [u8, u16, u32] + // Here: all are given and definitely contain no lifetimes, so we + // don't have any annotation. + let x = >::method::; x(&22, 44, 66); + // Here: all are given and we have a lifetime. + let x = >::method::; //~ ERROR [u8, &ReStatic u16, u32] + x(&22, &44, 66); + // Here: we want in particular that *only* the method `U` // annotation is given, the rest are variables. // diff --git a/src/test/ui/nll/user-annotations/dump-fn-method.stderr b/src/test/ui/nll/user-annotations/dump-fn-method.stderr index a1a4e43e8a3e9..04ceb8e5f8495 100644 --- a/src/test/ui/nll/user-annotations/dump-fn-method.stderr +++ b/src/test/ui/nll/user-annotations/dump-fn-method.stderr @@ -1,23 +1,23 @@ -error: user substs: UserSubsts { substs: [u32], user_self_ty: None } - --> $DIR/dump-fn-method.rs:26:13 +error: user substs: UserSubsts { substs: [&ReStatic u32], user_self_ty: None } + --> $DIR/dump-fn-method.rs:30:13 | -LL | let x = foo::; //~ ERROR [u32] - | ^^^^^^^^^^ +LL | let x = foo::<&'static u32>; //~ ERROR [&ReStatic u32] + | ^^^^^^^^^^^^^^^^^^^ error: user substs: UserSubsts { substs: [^0, u32, ^1], user_self_ty: None } - --> $DIR/dump-fn-method.rs:32:13 + --> $DIR/dump-fn-method.rs:36:13 | LL | let x = <_ as Bazoom>::method::<_>; //~ ERROR [^0, u32, ^1] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -error: user substs: UserSubsts { substs: [u8, u16, u32], user_self_ty: None } - --> $DIR/dump-fn-method.rs:36:13 +error: user substs: UserSubsts { substs: [u8, &ReStatic u16, u32], user_self_ty: None } + --> $DIR/dump-fn-method.rs:45:13 | -LL | let x = >::method::; //~ ERROR [u8, u16, u32] - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +LL | let x = >::method::; //~ ERROR [u8, &ReStatic u16, u32] + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: user substs: UserSubsts { substs: [^0, ^1, u32], user_self_ty: None } - --> $DIR/dump-fn-method.rs:44:5 + --> $DIR/dump-fn-method.rs:53:5 | LL | y.method::(44, 66); //~ ERROR [^0, ^1, u32] | ^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/src/test/ui/nll/user-annotations/inherent-associated-constants.rs b/src/test/ui/nll/user-annotations/inherent-associated-constants.rs new file mode 100644 index 0000000000000..2490187605ac1 --- /dev/null +++ b/src/test/ui/nll/user-annotations/inherent-associated-constants.rs @@ -0,0 +1,17 @@ +#![feature(nll)] + +struct A<'a>(&'a ()); + +impl A<'static> { + const IC: i32 = 10; +} + +fn non_wf_associated_const<'a>(x: i32) { + A::<'a>::IC; //~ ERROR lifetime may not live long enough +} + +fn wf_associated_const<'a>(x: i32) { + A::<'static>::IC; +} + +fn main() {} diff --git a/src/test/ui/nll/user-annotations/inherent-associated-constants.stderr b/src/test/ui/nll/user-annotations/inherent-associated-constants.stderr new file mode 100644 index 0000000000000..785b39ec887a0 --- /dev/null +++ b/src/test/ui/nll/user-annotations/inherent-associated-constants.stderr @@ -0,0 +1,10 @@ +error: lifetime may not live long enough + --> $DIR/inherent-associated-constants.rs:10:5 + | +LL | fn non_wf_associated_const<'a>(x: i32) { + | -- lifetime `'a` defined here +LL | A::<'a>::IC; //~ ERROR lifetime may not live long enough + | ^^^^^^^^^^^ requires that `'a` must outlive `'static` + +error: aborting due to previous error +