diff --git a/src/librustc/middle/ty.rs b/src/librustc/middle/ty.rs index 7cda6c21853a3..22f5c5cdbcda4 100644 --- a/src/librustc/middle/ty.rs +++ b/src/librustc/middle/ty.rs @@ -6891,6 +6891,7 @@ pub enum CopyImplementationError { FieldDoesNotImplementCopy(ast::Name), VariantDoesNotImplementCopy(ast::Name), TypeIsStructural, + TypeHasDestructor, } pub fn can_type_implement_copy<'a,'tcx>(param_env: &ParameterEnvironment<'a, 'tcx>, @@ -6900,7 +6901,7 @@ pub fn can_type_implement_copy<'a,'tcx>(param_env: &ParameterEnvironment<'a, 'tc { let tcx = param_env.tcx; - match self_type.sty { + let did = match self_type.sty { ty::ty_struct(struct_did, substs) => { let fields = ty::struct_fields(tcx, struct_did, substs); for field in fields.iter() { @@ -6908,6 +6909,7 @@ pub fn can_type_implement_copy<'a,'tcx>(param_env: &ParameterEnvironment<'a, 'tc return Err(FieldDoesNotImplementCopy(field.name)) } } + struct_did } ty::ty_enum(enum_did, substs) => { let enum_variants = ty::enum_variants(tcx, enum_did); @@ -6920,8 +6922,13 @@ pub fn can_type_implement_copy<'a,'tcx>(param_env: &ParameterEnvironment<'a, 'tc } } } + enum_did } _ => return Err(TypeIsStructural), + }; + + if ty::has_dtor(tcx, did) { + return Err(TypeHasDestructor) } Ok(()) diff --git a/src/librustc_typeck/coherence/mod.rs b/src/librustc_typeck/coherence/mod.rs index 09ab98745bd6a..de1f1a3cd352a 100644 --- a/src/librustc_typeck/coherence/mod.rs +++ b/src/librustc_typeck/coherence/mod.rs @@ -507,6 +507,11 @@ impl<'a, 'tcx> CoherenceChecker<'a, 'tcx> { for this type; type is not a structure or \ enumeration") } + Err(ty::TypeHasDestructor) => { + span_err!(tcx.sess, span, E0184, + "the trait `Copy` may not be implemented for this type; \ + the type has a destructor"); + } } } } diff --git a/src/librustc_typeck/diagnostics.rs b/src/librustc_typeck/diagnostics.rs index 9657bf82a8b81..c9e15b93ad4c5 100644 --- a/src/librustc_typeck/diagnostics.rs +++ b/src/librustc_typeck/diagnostics.rs @@ -157,5 +157,6 @@ register_diagnostics! { E0180, E0181, E0182, - E0183 + E0183, + E0184 } diff --git a/src/test/compile-fail/drop-on-non-struct.rs b/src/test/compile-fail/drop-on-non-struct.rs index 8304afa1141ee..d35157e26b2bd 100644 --- a/src/test/compile-fail/drop-on-non-struct.rs +++ b/src/test/compile-fail/drop-on-non-struct.rs @@ -8,7 +8,7 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. -impl Drop for int { +impl<'a> Drop for &'a mut int { //~^ ERROR the Drop trait may only be implemented on structures //~^^ ERROR cannot provide an extension implementation fn drop(&mut self) { diff --git a/src/test/compile-fail/exclusive-drop-and-copy.rs b/src/test/compile-fail/exclusive-drop-and-copy.rs new file mode 100644 index 0000000000000..17453bc677f2b --- /dev/null +++ b/src/test/compile-fail/exclusive-drop-and-copy.rs @@ -0,0 +1,30 @@ +// Copyright 2015 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![feature(unsafe_destructor)] + +// issue #20126 + +#[derive(Copy)] //~ ERROR the trait `Copy` may not be implemented +struct Foo; + +impl Drop for Foo { + fn drop(&mut self) {} +} + +#[derive(Copy)] //~ ERROR the trait `Copy` may not be implemented +struct Bar; + +#[unsafe_destructor] +impl Drop for Bar { + fn drop(&mut self) {} +} + +fn main() {}