From 638b7c89e6c3de5c21cf10ea28b8b8ea259b5f27 Mon Sep 17 00:00:00 2001 From: Federico Ravasio Date: Sun, 28 Aug 2016 12:51:00 +0200 Subject: [PATCH 1/3] Updated E0493 to new format. --- src/librustc_mir/transform/qualify_consts.rs | 4 ++++ src/test/compile-fail/E0493.rs | 4 +++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/src/librustc_mir/transform/qualify_consts.rs b/src/librustc_mir/transform/qualify_consts.rs index 9e076851bc37..a6f6faf24696 100644 --- a/src/librustc_mir/transform/qualify_consts.rs +++ b/src/librustc_mir/transform/qualify_consts.rs @@ -252,11 +252,15 @@ impl<'a, 'tcx> Qualifier<'a, 'tcx, 'tcx> { let mut err = struct_span_err!(self.tcx.sess, self.span, E0493, "{}", msg); + if self.mode != Mode::Const { help!(&mut err, "in Nightly builds, add `#![feature(drop_types_in_const)]` \ to the crate attributes to enable"); + } else { + err.span_label(self.span, &format!("constants cannot have destructors")); } + err.emit(); } diff --git a/src/test/compile-fail/E0493.rs b/src/test/compile-fail/E0493.rs index 689f469533d9..d5b29a628f0b 100644 --- a/src/test/compile-fail/E0493.rs +++ b/src/test/compile-fail/E0493.rs @@ -16,7 +16,9 @@ impl Drop for Foo { fn drop(&mut self) {} } -const F : Foo = Foo { a : 0 }; //~ ERROR E0493 +const F : Foo = Foo { a : 0 }; +//~^ ERROR constants are not allowed to have destructors [E0493] +//~| NOTE constants cannot have destructors fn main() { } From ed5e5df596aff90b4147869e3464330f7833f81e Mon Sep 17 00:00:00 2001 From: Federico Ravasio Date: Fri, 2 Sep 2016 11:44:46 +0200 Subject: [PATCH 2/3] E0493: showing a label where the destructor is defined. --- src/librustc_mir/transform/qualify_consts.rs | 29 ++++++++++++++++++++ src/test/compile-fail/E0493.rs | 9 ++++++ 2 files changed, 38 insertions(+) diff --git a/src/librustc_mir/transform/qualify_consts.rs b/src/librustc_mir/transform/qualify_consts.rs index a6f6faf24696..14a432cbb895 100644 --- a/src/librustc_mir/transform/qualify_consts.rs +++ b/src/librustc_mir/transform/qualify_consts.rs @@ -18,6 +18,7 @@ use rustc_data_structures::bitvec::BitVector; use rustc_data_structures::indexed_vec::{IndexVec, Idx}; use rustc::dep_graph::DepNode; use rustc::hir; +use rustc::hir::map as hir_map; use rustc::hir::def_id::DefId; use rustc::hir::intravisit::FnKind; use rustc::hir::map::blocks::FnLikeNode; @@ -258,12 +259,40 @@ impl<'a, 'tcx> Qualifier<'a, 'tcx, 'tcx> { "in Nightly builds, add `#![feature(drop_types_in_const)]` \ to the crate attributes to enable"); } else { + self.find_drop_implementation_method_span() + .map(|span| err.span_label(span, &format!("destructor defined here"))); + err.span_label(self.span, &format!("constants cannot have destructors")); } err.emit(); } + fn find_drop_implementation_method_span(&self) -> Option { + self.tcx.lang_items + .drop_trait() + .and_then(|drop_trait_id| { + let mut span = None; + + self.tcx + .lookup_trait_def(drop_trait_id) + .for_each_relevant_impl(self.tcx, self.mir.return_ty, |impl_did| { + self.tcx.map + .as_local_node_id(impl_did) + .and_then(|impl_node_id| self.tcx.map.find(impl_node_id)) + .map(|node| { + if let hir_map::NodeItem(item) = node { + if let hir::ItemImpl(_, _, _, _, _, ref methods) = item.node { + span = methods.first().map(|method| method.span); + } + } + }); + }); + + span + }) + } + /// Check if an Lvalue with the current qualifications could /// be consumed, by either an operand or a Deref projection. fn try_consume(&mut self) -> bool { diff --git a/src/test/compile-fail/E0493.rs b/src/test/compile-fail/E0493.rs index d5b29a628f0b..e06da5ca7c55 100644 --- a/src/test/compile-fail/E0493.rs +++ b/src/test/compile-fail/E0493.rs @@ -14,6 +14,15 @@ struct Foo { impl Drop for Foo { fn drop(&mut self) {} + //~^ NOTE destructor defined here +} + +struct Bar { + a: u32 +} + +impl Drop for Bar { + fn drop(&mut self) {} } const F : Foo = Foo { a : 0 }; From 059094f3f264a683e624ae57b475264b5ce8511c Mon Sep 17 00:00:00 2001 From: Federico Ravasio Date: Fri, 2 Sep 2016 19:55:14 +0200 Subject: [PATCH 3/3] Moved test on E0493 from compile-fail to ui. --- src/test/{compile-fail => ui/span}/E0493.rs | 3 --- src/test/ui/span/E0493.stderr | 11 +++++++++++ 2 files changed, 11 insertions(+), 3 deletions(-) rename src/test/{compile-fail => ui/span}/E0493.rs (81%) create mode 100644 src/test/ui/span/E0493.stderr diff --git a/src/test/compile-fail/E0493.rs b/src/test/ui/span/E0493.rs similarity index 81% rename from src/test/compile-fail/E0493.rs rename to src/test/ui/span/E0493.rs index e06da5ca7c55..ea4526b70f6a 100644 --- a/src/test/compile-fail/E0493.rs +++ b/src/test/ui/span/E0493.rs @@ -14,7 +14,6 @@ struct Foo { impl Drop for Foo { fn drop(&mut self) {} - //~^ NOTE destructor defined here } struct Bar { @@ -26,8 +25,6 @@ impl Drop for Bar { } const F : Foo = Foo { a : 0 }; -//~^ ERROR constants are not allowed to have destructors [E0493] -//~| NOTE constants cannot have destructors fn main() { } diff --git a/src/test/ui/span/E0493.stderr b/src/test/ui/span/E0493.stderr new file mode 100644 index 000000000000..afcc9a240eb4 --- /dev/null +++ b/src/test/ui/span/E0493.stderr @@ -0,0 +1,11 @@ +error[E0493]: constants are not allowed to have destructors + --> $DIR/E0493.rs:27:17 + | +16 | fn drop(&mut self) {} + | --------------------- destructor defined here +... +27 | const F : Foo = Foo { a : 0 }; + | ^^^^^^^^^^^^^ constants cannot have destructors + +error: aborting due to previous error +