}
};
if let PlaceContext::Copy = context {
- let ty = place_ty.to_ty(self.tcx());
- if self.cx
- .infcx
- .type_moves_by_default(self.cx.param_env, ty, DUMMY_SP)
- {
- span_mirbug!(self, place, "attempted copy of non-Copy type ({:?})", ty);
- }
+ let tcx = self.tcx();
+ let trait_ref = ty::TraitRef {
+ def_id: tcx.lang_items().copy_trait().unwrap(),
+ substs: tcx.mk_substs_trait(place_ty.to_ty(tcx), &[]),
+ };
+
+ // In order to have a Copy operand, the type T of the value must be Copy. Note that we
+ // prove that T: Copy, rather than using the type_moves_by_default test. This is
+ // important because type_moves_by_default ignores the resulting region obligations and
+ // assumes they pass. This can result in bounds from Copy impls being unsoundly ignored
+ // (e.g., #29149). Note that we decide to use Copy before knowing whether the bounds
+ // fully apply: in effect, the rule is that if a value of some type could implement
+ // Copy, then it must.
+ self.cx.prove_trait_ref(trait_ref, location);
}
place_ty
}
--- /dev/null
+// Copyright 2012 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Test that the 'static bound from the Copy impl is respected. Regression test for #29149.
+
+#![feature(nll)]
+
+#[derive(Clone)] struct Foo<'a>(&'a u32);
+impl Copy for Foo<'static> {}
+
+fn main() {
+ let s = 2;
+ let a = Foo(&s); //~ ERROR `s` does not live long enough [E0597]
+ drop(a);
+ drop(a);
+}