Add ICEs 77696, 77910, 77911, 77919 (#504)

* Add ICE 77696

* Add ICE 77919

* Add ICE 77911

* Add ICE 77910

* Add end of file newline

ices/77696.rs

@@ -0,0 +1,10 @@
+#![feature(impl_trait_in_bindings)]
+
+struct S;
+trait Trait {
+    fn demo(&self) {}
+}
+impl Trait for S {}
+fn main() {
+    let a: &impl Trait = &S;
+}

ices/77910.rs

@@ -0,0 +1,9 @@
+fn foo(s: &i32) -> &i32 {
+    let xs;
+    xs
+}
+
+fn main() {
+    let y;
+    assert_eq!(foo, y);
+}

ices/77911.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+rustc -Z mir-opt-level=2 - << EOF
+use std::fs::File;
+use std::io::{BufRead, BufReader};
+
+fn file_lines() -> impl Iterator<Item = String> {
+    BufReader::new(File::open("data.txt").unwrap())
+        .lines()
+        .map(Result::unwrap)
+}
+
+fn main() {
+    for _ in file_lines() {}
+}
+
+EOF

ices/77919.rs

@@ -0,0 +1,12 @@
+trait TypeVal<T> {
+    const VAL: T;
+}
+struct Five;
+struct Multiply<N, M> {
+    _n: PhantomData,
+}
+impl<N, M> TypeVal<usize> for Multiply<N, M> where N: TypeVal<VAL> {}
+
+fn main() {
+    [1; <Multiply<Five, Five>>::VAL];
+}