diff options
Diffstat (limited to 'compiler/rustc_resolve/src/ident.rs')
| -rw-r--r-- | compiler/rustc_resolve/src/ident.rs | 75 |
1 files changed, 65 insertions, 10 deletions
diff --git a/compiler/rustc_resolve/src/ident.rs b/compiler/rustc_resolve/src/ident.rs index 0c4b35b8833..75981885674 100644 --- a/compiler/rustc_resolve/src/ident.rs +++ b/compiler/rustc_resolve/src/ident.rs @@ -1,9 +1,11 @@ -use rustc_ast as ast; +use rustc_ast::{self as ast, NodeId}; use rustc_feature::is_builtin_attr_name; use rustc_hir::def::{DefKind, Namespace, NonMacroAttrKind, PartialRes, PerNS}; use rustc_hir::PrimTy; use rustc_middle::bug; use rustc_middle::ty; +use rustc_session::lint::builtin::PROC_MACRO_DERIVE_RESOLUTION_FALLBACK; +use rustc_session::lint::BuiltinLintDiagnostics; use rustc_span::def_id::LocalDefId; use rustc_span::edition::Edition; use rustc_span::hygiene::{ExpnId, ExpnKind, LocalExpnId, MacroKind, SyntaxContext}; @@ -99,7 +101,7 @@ impl<'a> Resolver<'a> { }; let mut scope = match ns { _ if is_absolute_path => Scope::CrateRoot, - TypeNS | ValueNS => Scope::Module(module), + TypeNS | ValueNS => Scope::Module(module, None), MacroNS => Scope::DeriveHelpers(parent_scope.expansion), }; let mut ctxt = ctxt.normalize_to_macros_2_0(); @@ -163,7 +165,7 @@ impl<'a> Resolver<'a> { MacroRulesScope::Invocation(invoc_id) => { Scope::MacroRules(self.invocation_parent_scopes[&invoc_id].macro_rules) } - MacroRulesScope::Empty => Scope::Module(module), + MacroRulesScope::Empty => Scope::Module(module, None), }, Scope::CrateRoot => match ns { TypeNS => { @@ -172,10 +174,16 @@ impl<'a> Resolver<'a> { } ValueNS | MacroNS => break, }, - Scope::Module(module) => { + Scope::Module(module, prev_lint_id) => { use_prelude = !module.no_implicit_prelude; - match self.hygienic_lexical_parent(module, &mut ctxt) { - Some(parent_module) => Scope::Module(parent_module), + let derive_fallback_lint_id = match scope_set { + ScopeSet::Late(.., lint_id) => lint_id, + _ => None, + }; + match self.hygienic_lexical_parent(module, &mut ctxt, derive_fallback_lint_id) { + Some((parent_module, lint_id)) => { + Scope::Module(parent_module, lint_id.or(prev_lint_id)) + } None => { ctxt.adjust(ExpnId::root()); match ns { @@ -207,13 +215,45 @@ impl<'a> Resolver<'a> { &mut self, module: Module<'a>, ctxt: &mut SyntaxContext, - ) -> Option<Module<'a>> { + derive_fallback_lint_id: Option<NodeId>, + ) -> Option<(Module<'a>, Option<NodeId>)> { if !module.expansion.outer_expn_is_descendant_of(*ctxt) { - return Some(self.expn_def_scope(ctxt.remove_mark())); + return Some((self.expn_def_scope(ctxt.remove_mark()), None)); } if let ModuleKind::Block = module.kind { - return Some(module.parent.unwrap().nearest_item_scope()); + return Some((module.parent.unwrap().nearest_item_scope(), None)); + } + + // We need to support the next case under a deprecation warning + // ``` + // struct MyStruct; + // ---- begin: this comes from a proc macro derive + // mod implementation_details { + // // Note that `MyStruct` is not in scope here. + // impl SomeTrait for MyStruct { ... } + // } + // ---- end + // ``` + // So we have to fall back to the module's parent during lexical resolution in this case. + if derive_fallback_lint_id.is_some() { + if let Some(parent) = module.parent { + // Inner module is inside the macro, parent module is outside of the macro. + if module.expansion != parent.expansion + && module.expansion.is_descendant_of(parent.expansion) + { + // The macro is a proc macro derive + if let Some(def_id) = module.expansion.expn_data().macro_def_id { + let ext = self.get_macro_by_def_id(def_id).ext; + if ext.builtin_name.is_none() + && ext.macro_kind() == MacroKind::Derive + && parent.expansion.outer_expn_is_descendant_of(*ctxt) + { + return Some((parent, derive_fallback_lint_id)); + } + } + } + } } None @@ -470,7 +510,7 @@ impl<'a> Resolver<'a> { Err((Determinacy::Determined, _)) => Err(Determinacy::Determined), } } - Scope::Module(module) => { + Scope::Module(module, derive_fallback_lint_id) => { let adjusted_parent_scope = &ParentScope { module, ..*parent_scope }; let binding = this.resolve_ident_in_module_unadjusted_ext( ModuleOrUniformRoot::Module(module), @@ -483,6 +523,21 @@ impl<'a> Resolver<'a> { ); match binding { Ok(binding) => { + if let Some(lint_id) = derive_fallback_lint_id { + this.lint_buffer.buffer_lint_with_diagnostic( + PROC_MACRO_DERIVE_RESOLUTION_FALLBACK, + lint_id, + orig_ident.span, + &format!( + "cannot find {} `{}` in this scope", + ns.descr(), + ident + ), + BuiltinLintDiagnostics::ProcMacroDeriveResolutionFallback( + orig_ident.span, + ), + ); + } let misc_flags = if ptr::eq(module, this.graph_root) { Flags::MISC_SUGGEST_CRATE } else if module.is_normal() { |