From 7be2019428ff888ea26075a065fa3cebb66c5ead Mon Sep 17 00:00:00 2001 From: "Felix S. Klock II" Date: Mon, 23 Jun 2014 14:17:18 +0200 Subject: [PATCH] Add regression test for ICE from issue 10846. --- .../regions-lifetime-nonfree-late-bound.rs | 40 +++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 src/test/run-pass/regions-lifetime-nonfree-late-bound.rs diff --git a/src/test/run-pass/regions-lifetime-nonfree-late-bound.rs b/src/test/run-pass/regions-lifetime-nonfree-late-bound.rs new file mode 100644 index 00000000000..1c2e50a5f76 --- /dev/null +++ b/src/test/run-pass/regions-lifetime-nonfree-late-bound.rs @@ -0,0 +1,40 @@ +// Copyright 2014 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. + +// This is a regression test for the ICE from issue #10846. +// +// The original issue causing the ICE: the LUB-computations during +// type inference were encountering late-bound lifetimes, and +// asserting that such lifetimes should have already been subsituted +// with a concrete lifetime. +// +// However, those encounters were occurring within the lexical scope +// of the binding for the late-bound lifetime; that is, the late-bound +// lifetimes were perfectly valid. The core problem was that the type +// folding code was over-zealously passing back all lifetimes when +// doing region-folding, when really all clients of the region-folding +// case only want to see FREE lifetime variables, not bound ones. + +pub fn main() { + fn explicit() { + fn test(_x: Option<|f: <'a> |g: &'a int||>) {} + test(Some(|_f: <'a> |g: &'a int|| {})); + } + + // The code below is shorthand for the code above (and more likely + // to represent what one encounters in practice). + fn implicit() { + fn test(_x: Option<|f: |g: & int||>) {} + test(Some(|_f: |g: & int|| {})); + } + + explicit(); + implicit(); +} -- 2.44.0