rustc: Avoid UB with signed division/remainder

Division and remainder by 0 are undefined behavior, and are detected at runtime.
This commit adds support for ensuring that MIN / -1 is also checked for at
runtime, as this would cause signed overflow, or undefined behvaior.

Closes #8460

src/test/run-pass/issue-8460.rs

@@ -0,0 +1,35 @@
+// 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 <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.
+
+use std::{int, i8, i16, i32, i64};
+use std::task;
+
+fn main() {
+    assert!(task::try(proc() int::MIN / -1).is_err());
+    assert!(task::try(proc() i8::MIN / -1).is_err());
+    assert!(task::try(proc() i16::MIN / -1).is_err());
+    assert!(task::try(proc() i32::MIN / -1).is_err());
+    assert!(task::try(proc() i64::MIN / -1).is_err());
+    assert!(task::try(proc() 1i / 0).is_err());
+    assert!(task::try(proc() 1i8 / 0).is_err());
+    assert!(task::try(proc() 1i16 / 0).is_err());
+    assert!(task::try(proc() 1i32 / 0).is_err());
+    assert!(task::try(proc() 1i64 / 0).is_err());
+    assert!(task::try(proc() int::MIN % -1).is_err());
+    assert!(task::try(proc() i8::MIN % -1).is_err());
+    assert!(task::try(proc() i16::MIN % -1).is_err());
+    assert!(task::try(proc() i32::MIN % -1).is_err());
+    assert!(task::try(proc() i64::MIN % -1).is_err());
+    assert!(task::try(proc() 1i % 0).is_err());
+    assert!(task::try(proc() 1i8 % 0).is_err());
+    assert!(task::try(proc() 1i16 % 0).is_err());
+    assert!(task::try(proc() 1i32 % 0).is_err());
+    assert!(task::try(proc() 1i64 % 0).is_err());
+}