diff --git a/src/librustc_hir/def.rs b/src/librustc_hir/def.rs index 696aa5c6f7dfe..3334cc32a52f7 100644 --- a/src/librustc_hir/def.rs +++ b/src/librustc_hir/def.rs @@ -159,6 +159,7 @@ impl DefKind { } } +/// The resolution of a path or export. #[derive(Clone, Copy, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)] #[derive(HashStable_Generic)] pub enum Res { diff --git a/src/librustc_typeck/collect/type_of.rs b/src/librustc_typeck/collect/type_of.rs index 55642dfb4557b..16c8689ae0cbc 100644 --- a/src/librustc_typeck/collect/type_of.rs +++ b/src/librustc_typeck/collect/type_of.rs @@ -235,29 +235,31 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> { }; if let Some(path) = path { - let arg_index = path + // We've encountered an `AnonConst` in some path, so we need to + // figure out which generic parameter it corresponds to and return + // the relevant type. + + let (arg_index, segment) = path .segments .iter() - .filter_map(|seg| seg.args.as_ref()) - .map(|generic_args| generic_args.args) - .find_map(|args| { + .filter_map(|seg| seg.args.as_ref().map(|args| (args.args, seg))) + .find_map(|(args, seg)| { args.iter() .filter(|arg| arg.is_const()) .enumerate() .filter(|(_, arg)| arg.id() == hir_id) - .map(|(index, _)| index) + .map(|(index, _)| (index, seg)) .next() }) .unwrap_or_else(|| { bug!("no arg matching AnonConst in path"); }); - // We've encountered an `AnonConst` in some path, so we need to - // figure out which generic parameter it corresponds to and return - // the relevant type. - let generics = match path.res { - Res::Def(DefKind::Ctor(..), def_id) - | Res::Def(DefKind::AssocTy, def_id) => { + // Try to use the segment resolution if it is valid, otherwise we + // default to the path resolution. + let res = segment.res.filter(|&r| r != Res::Err).unwrap_or(path.res); + let generics = match res { + Res::Def(DefKind::Ctor(..), def_id) => { tcx.generics_of(tcx.parent(def_id).unwrap()) } Res::Def(_, def_id) => tcx.generics_of(def_id), @@ -265,8 +267,8 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> { tcx.sess.delay_span_bug( DUMMY_SP, &format!( - "unexpected const parent path def, parent: {:?}, def: {:?}", - parent_node, res + "unexpected anon const res {:?} in path: {:?}", + res, path, ), ); return tcx.types.err; @@ -291,8 +293,8 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> { tcx.sess.delay_span_bug( DUMMY_SP, &format!( - "missing generic parameter for `AnonConst`, parent {:?}", - parent_node + "missing generic parameter for `AnonConst`, parent: {:?}, res: {:?}", + parent_node, res ), ); tcx.types.err diff --git a/src/librustc_typeck/lib.rs b/src/librustc_typeck/lib.rs index e487e0d265c3e..fd854c750184e 100644 --- a/src/librustc_typeck/lib.rs +++ b/src/librustc_typeck/lib.rs @@ -62,6 +62,7 @@ This API is completely unstable and subject to change. #![feature(crate_visibility_modifier)] #![feature(in_band_lifetimes)] #![feature(nll)] +#![feature(or_patterns)] #![feature(try_blocks)] #![feature(never_type)] #![feature(slice_partition_dedup)] diff --git a/src/test/ui/const-generics/issues/issue70273-assoc-fn.rs b/src/test/ui/const-generics/issues/issue70273-assoc-fn.rs new file mode 100644 index 0000000000000..a192ddea9c6ab --- /dev/null +++ b/src/test/ui/const-generics/issues/issue70273-assoc-fn.rs @@ -0,0 +1,17 @@ +// check-pass + +#![feature(const_generics)] +//~^ WARN the feature `const_generics` is incomplete and may cause the compiler to crash + +trait T { + fn f(); +} +struct S; + +impl T<0usize> for S { + fn f() {} +} + +fn main() { + let _err = >::f(); +} diff --git a/src/test/ui/const-generics/issues/issue70273-assoc-fn.stderr b/src/test/ui/const-generics/issues/issue70273-assoc-fn.stderr new file mode 100644 index 0000000000000..64007ade0f2ed --- /dev/null +++ b/src/test/ui/const-generics/issues/issue70273-assoc-fn.stderr @@ -0,0 +1,8 @@ +warning: the feature `const_generics` is incomplete and may cause the compiler to crash + --> $DIR/issue70273-assoc-fn.rs:3:12 + | +LL | #![feature(const_generics)] + | ^^^^^^^^^^^^^^ + | + = note: `#[warn(incomplete_features)]` on by default + diff --git a/src/test/ui/const-generics/type_of_anon_const.rs b/src/test/ui/const-generics/type_of_anon_const.rs new file mode 100644 index 0000000000000..776084b77a577 --- /dev/null +++ b/src/test/ui/const-generics/type_of_anon_const.rs @@ -0,0 +1,21 @@ +// run-pass + +#![feature(const_generics)] +//~^ WARN the feature `const_generics` is incomplete and may cause the compiler to crash + +trait T { + fn l() -> usize; + fn r() -> bool; +} + +struct S; + +impl T for S { + fn l() -> usize { N } + fn r() -> bool { M } +} + +fn main() { + assert_eq!(>::l::(), 123); + assert!(>::r::()); +} diff --git a/src/test/ui/const-generics/type_of_anon_const.stderr b/src/test/ui/const-generics/type_of_anon_const.stderr new file mode 100644 index 0000000000000..495d34ce09b81 --- /dev/null +++ b/src/test/ui/const-generics/type_of_anon_const.stderr @@ -0,0 +1,8 @@ +warning: the feature `const_generics` is incomplete and may cause the compiler to crash + --> $DIR/type_of_anon_const.rs:3:12 + | +LL | #![feature(const_generics)] + | ^^^^^^^^^^^^^^ + | + = note: `#[warn(incomplete_features)]` on by default +