From fba2f883f39332f43d9cd8f69ebc720076e64e0d Mon Sep 17 00:00:00 2001 From: Kevin Per Date: Wed, 10 Feb 2021 15:49:23 +0000 Subject: [PATCH] Implementing more sophisticated filter for fn in const or static --- compiler/rustc_typeck/src/astconv/mod.rs | 6 ++- compiler/rustc_typeck/src/check/mod.rs | 1 + compiler/rustc_typeck/src/collect.rs | 69 ++++++++++++++++++------ 3 files changed, 59 insertions(+), 17 deletions(-) diff --git a/compiler/rustc_typeck/src/astconv/mod.rs b/compiler/rustc_typeck/src/astconv/mod.rs index 66bded85f3f67..120a59aa9d252 100644 --- a/compiler/rustc_typeck/src/astconv/mod.rs +++ b/compiler/rustc_typeck/src/astconv/mod.rs @@ -2145,12 +2145,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { } hir::TyKind::BareFn(ref bf) => { require_c_abi_if_c_variadic(tcx, &bf.decl, bf.abi, ast_ty.span); + tcx.mk_fn_ptr(self.ty_of_fn( bf.unsafety, bf.abi, &bf.decl, &hir::Generics::empty(), None, + Some(ast_ty), )) } hir::TyKind::TraitObject(ref bounds, ref lifetime) => { @@ -2290,6 +2292,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { decl: &hir::FnDecl<'_>, generics: &hir::Generics<'_>, ident_span: Option, + hir_ty: Option<&hir::Ty<'_>>, ) -> ty::PolyFnSig<'tcx> { debug!("ty_of_fn"); @@ -2321,13 +2324,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { // only want to emit an error complaining about them if infer types (`_`) are not // allowed. `allow_ty_infer` gates this behavior. We check for the presence of // `ident_span` to not emit an error twice when we have `fn foo(_: fn() -> _)`. + crate::collect::placeholder_type_error( tcx, ident_span.map(|sp| sp.shrink_to_hi()), &generics.params[..], visitor.0, true, - true, + hir_ty, ); } diff --git a/compiler/rustc_typeck/src/check/mod.rs b/compiler/rustc_typeck/src/check/mod.rs index 229127e95d93c..fce7ae8119e17 100644 --- a/compiler/rustc_typeck/src/check/mod.rs +++ b/compiler/rustc_typeck/src/check/mod.rs @@ -502,6 +502,7 @@ fn typeck_with_fallback<'tcx>( decl, &hir::Generics::empty(), None, + None, ) } else { tcx.fn_sig(def_id) diff --git a/compiler/rustc_typeck/src/collect.rs b/compiler/rustc_typeck/src/collect.rs index 58e083f2c240a..754fc6a9c7b21 100644 --- a/compiler/rustc_typeck/src/collect.rs +++ b/compiler/rustc_typeck/src/collect.rs @@ -141,7 +141,7 @@ crate fn placeholder_type_error( generics: &[hir::GenericParam<'_>], placeholder_types: Vec, suggest: bool, - is_fn: bool, + hir_ty: Option<&hir::Ty<'_>>, ) { if placeholder_types.is_empty() { return; @@ -173,13 +173,39 @@ crate fn placeholder_type_error( let mut err = bad_placeholder_type(tcx, placeholder_types); - // Suggest, but only if it is not a function - if suggest && !is_fn { - err.multipart_suggestion( - "use type parameters instead", - sugg, - Applicability::HasPlaceholders, - ); + // Suggest, but only if it is not a function in const or static + if suggest { + let mut is_fn = false; + let mut is_const = false; + let mut is_static = false; + + if let Some(hir_ty) = hir_ty { + if let hir::TyKind::BareFn(_) = hir_ty.kind { + is_fn = true; + + // Check if parent is const or static + let parent_id = tcx.hir().get_parent_node(hir_ty.hir_id); + let parent_node = tcx.hir().get(parent_id); + + if let hir::Node::Item(item) = parent_node { + if let hir::ItemKind::Const(_, _) = item.kind { + is_const = true; + } else if let hir::ItemKind::Static(_, _, _) = item.kind { + is_static = true; + } + } + } + } + + // if function is wrapped around a const or static, + // then don't show the suggestion + if !(is_fn && (is_const || is_static)) { + err.multipart_suggestion( + "use type parameters instead", + sugg, + Applicability::HasPlaceholders, + ); + } } err.emit(); } @@ -207,7 +233,7 @@ fn reject_placeholder_type_signatures_in_item(tcx: TyCtxt<'tcx>, item: &'tcx hir &generics.params[..], visitor.0, suggest, - false, + None, ); } @@ -648,6 +674,7 @@ fn convert_item(tcx: TyCtxt<'_>, item_id: hir::HirId) { let it = tcx.hir().expect_item(item_id); debug!("convert: item {} with id {}", it.ident, it.hir_id); let def_id = tcx.hir().local_def_id(item_id); + match it.kind { // These don't define types. hir::ItemKind::ExternCrate(_) @@ -753,7 +780,7 @@ fn convert_trait_item(tcx: TyCtxt<'_>, trait_item_id: hir::HirId) { // Account for `const C: _;`. let mut visitor = PlaceholderHirTyCollector::default(); visitor.visit_trait_item(trait_item); - placeholder_type_error(tcx, None, &[], visitor.0, false, false); + placeholder_type_error(tcx, None, &[], visitor.0, false, None); } hir::TraitItemKind::Type(_, Some(_)) => { @@ -762,7 +789,7 @@ fn convert_trait_item(tcx: TyCtxt<'_>, trait_item_id: hir::HirId) { // Account for `type T = _;`. let mut visitor = PlaceholderHirTyCollector::default(); visitor.visit_trait_item(trait_item); - placeholder_type_error(tcx, None, &[], visitor.0, false, false); + placeholder_type_error(tcx, None, &[], visitor.0, false, None); } hir::TraitItemKind::Type(_, None) => { @@ -771,7 +798,8 @@ fn convert_trait_item(tcx: TyCtxt<'_>, trait_item_id: hir::HirId) { // even if there is no concrete type. let mut visitor = PlaceholderHirTyCollector::default(); visitor.visit_trait_item(trait_item); - placeholder_type_error(tcx, None, &[], visitor.0, false, false); + + placeholder_type_error(tcx, None, &[], visitor.0, false, None); } }; @@ -792,7 +820,8 @@ fn convert_impl_item(tcx: TyCtxt<'_>, impl_item_id: hir::HirId) { // Account for `type T = _;` let mut visitor = PlaceholderHirTyCollector::default(); visitor.visit_impl_item(impl_item); - placeholder_type_error(tcx, None, &[], visitor.0, false, false); + + placeholder_type_error(tcx, None, &[], visitor.0, false, None); } hir::ImplItemKind::Const(..) => {} } @@ -1583,6 +1612,7 @@ fn fn_sig(tcx: TyCtxt<'_>, def_id: DefId) -> ty::PolyFnSig<'_> { &sig.decl, &generics, Some(ident.span), + None, ), } } @@ -1592,9 +1622,15 @@ fn fn_sig(tcx: TyCtxt<'_>, def_id: DefId) -> ty::PolyFnSig<'_> { ident, generics, .. - }) => { - AstConv::ty_of_fn(&icx, header.unsafety, header.abi, decl, &generics, Some(ident.span)) - } + }) => AstConv::ty_of_fn( + &icx, + header.unsafety, + header.abi, + decl, + &generics, + Some(ident.span), + None, + ), ForeignItem(&hir::ForeignItem { kind: ForeignItemKind::Fn(ref fn_decl, _, _), @@ -2264,6 +2300,7 @@ fn compute_sig_of_foreign_fn_decl<'tcx>( decl, &hir::Generics::empty(), Some(ident.span), + None, ); // Feature gate SIMD types in FFI, since I am not sure that the