diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_resolve/src/imports.rs | 93 |
1 files changed, 53 insertions, 40 deletions
diff --git a/compiler/rustc_resolve/src/imports.rs b/compiler/rustc_resolve/src/imports.rs index 23ef9bf53a1..47d8e5993fd 100644 --- a/compiler/rustc_resolve/src/imports.rs +++ b/compiler/rustc_resolve/src/imports.rs @@ -304,23 +304,21 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> { let res = binding.res(); self.check_reserved_macro_name(key.ident, res); self.set_binding_parent_module(binding, module); - - let mut resolution = self.resolution(module, key).borrow_mut(); - let old_binding = resolution.binding(); - let mut t = Ok(()); - if let Some(old_binding) = resolution.binding { - if res == Res::Err && old_binding.res() != Res::Err { - // Do not override real bindings with `Res::Err`s from error recovery. - } else { + self.update_resolution(module, key, |this, resolution| { + if let Some(old_binding) = resolution.binding { + if res == Res::Err && old_binding.res() != Res::Err { + // Do not override real bindings with `Res::Err`s from error recovery. + return Ok(()); + } match (old_binding.is_glob_import(), binding.is_glob_import()) { (true, true) => { if res != old_binding.res() { - resolution.binding = Some(self.ambiguity( + resolution.binding = Some(this.ambiguity( AmbiguityKind::GlobVsGlob, old_binding, binding, )); - } else if !old_binding.vis.is_at_least(binding.vis, self.tcx) { + } else if !old_binding.vis.is_at_least(binding.vis, this.tcx) { // We are glob-importing the same item but with greater visibility. resolution.binding = Some(binding); } @@ -332,7 +330,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> { && key.ns == MacroNS && nonglob_binding.expansion != LocalExpnId::ROOT { - resolution.binding = Some(self.ambiguity( + resolution.binding = Some(this.ambiguity( AmbiguityKind::GlobVsExpanded, nonglob_binding, glob_binding, @@ -344,12 +342,12 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> { if let Some(old_binding) = resolution.shadowed_glob { assert!(old_binding.is_glob_import()); if glob_binding.res() != old_binding.res() { - resolution.shadowed_glob = Some(self.ambiguity( + resolution.shadowed_glob = Some(this.ambiguity( AmbiguityKind::GlobVsGlob, old_binding, glob_binding, )); - } else if !old_binding.vis.is_at_least(binding.vis, self.tcx) { + } else if !old_binding.vis.is_at_least(binding.vis, this.tcx) { resolution.shadowed_glob = Some(glob_binding); } } else { @@ -357,27 +355,53 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> { } } (false, false) => { - t = Err(old_binding); + return Err(old_binding); } } + } else { + resolution.binding = Some(binding); } - } else { - resolution.binding = Some(binding); - }; + Ok(()) + }) + } + + fn ambiguity( + &self, + kind: AmbiguityKind, + primary_binding: &'a NameBinding<'a>, + secondary_binding: &'a NameBinding<'a>, + ) -> &'a NameBinding<'a> { + self.arenas.alloc_name_binding(NameBinding { + ambiguity: Some((secondary_binding, kind)), + ..primary_binding.clone() + }) + } + + // Use `f` to mutate the resolution of the name in the module. + // If the resolution becomes a success, define it in the module's glob importers. + fn update_resolution<T, F>(&mut self, module: Module<'a>, key: BindingKey, f: F) -> T + where + F: FnOnce(&mut Resolver<'a, 'tcx>, &mut NameResolution<'a>) -> T, + { // Ensure that `resolution` isn't borrowed when defining in the module's glob importers, // during which the resolution might end up getting re-defined via a glob cycle. - let (binding, t) = match resolution.binding() { - _ if old_binding.is_some() => return t, - None => return t, - Some(binding) => match old_binding { - Some(old_binding) if ptr::eq(old_binding, binding) => return t, - _ => (binding, t), - }, + let (binding, t) = { + let resolution = &mut *self.resolution(module, key).borrow_mut(); + let old_binding = resolution.binding(); + + let t = f(self, resolution); + + match resolution.binding() { + _ if old_binding.is_some() => return t, + None => return t, + Some(binding) => match old_binding { + Some(old_binding) if ptr::eq(old_binding, binding) => return t, + _ => (binding, t), + }, + } }; - drop(resolution); - // Define `binding` in `module`s glob importers. for import in module.glob_importers.borrow_mut().iter() { let mut ident = key.ident; @@ -396,18 +420,6 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> { t } - fn ambiguity( - &self, - kind: AmbiguityKind, - primary_binding: &'a NameBinding<'a>, - secondary_binding: &'a NameBinding<'a>, - ) -> &'a NameBinding<'a> { - self.arenas.alloc_name_binding(NameBinding { - ambiguity: Some((secondary_binding, kind)), - ..primary_binding.clone() - }) - } - // Define a dummy resolution containing a `Res::Err` as a placeholder for a failed // or indeterminate resolution, also mark such failed imports as used to avoid duplicate diagnostics. fn import_dummy_binding(&mut self, import: &'a Import<'a>, is_indeterminate: bool) { @@ -757,8 +769,9 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> { .emit(); } let key = BindingKey::new(target, ns); - let mut resolution = this.resolution(parent, key).borrow_mut(); - resolution.single_imports.remove(&Interned::new_unchecked(import)); + this.update_resolution(parent, key, |_, resolution| { + resolution.single_imports.remove(&Interned::new_unchecked(import)); + }); } } } |