Bump mir-opt-level up 2 to 3 and 3 to 4 (#681)

Author: JohnTitor

fixed/67019.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-rustc +nightly --edition 2018 -Z mir-opt-level=2 - << EOF
+rustc +nightly --edition 2018 -Z mir-opt-level=3 - << EOF
 fn test(this: ((u8, u8),)) {
     assert!((this.0).1 == 0);
 }

fixed/68296.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-rustc -Zmir-opt-level=2 - << END
+rustc -Zmir-opt-level=3 - << END
 const FOO: *const u32 = { //~ ERROR any use of this value will cause an error
     let x = 42;
     &x

fixed/68841.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-rustc -Z mir-opt-level=2 --edition 2018 - << END
+rustc -Z mir-opt-level=3 --edition 2018 - << END
 #![feature(async_closure)]
 
 use std::future::Future;

fixed/71793.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-rustc +nightly --edition 2018 -Z mir-opt-level=2 - << EOF
+rustc +nightly --edition 2018 -Z mir-opt-level=3 - << EOF
 pub async fn connect() {}
 pub fn block_on<F: std::future::Future>(_: F) {}
 fn main() {

fixed/72181.sh

@@ -19,4 +19,4 @@ fn main() {
 
 EOF
 
-rustc -Zmir-opt-level=2 --emit=mir 72181.rs
+rustc -Zmir-opt-level=3 --emit=mir 72181.rs

fixed/72285.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-rustc -Z mir-opt-level=3 - << EOF
+rustc -Z mir-opt-level=4 - << EOF
 
 fn main() {
     let i = (0..usize::max_value()).chain(0..10).skip(usize::max_value());

fixed/72372.sh

@@ -8,4 +8,4 @@ fn main() {
 
 EOF
 
-rustc -Zmir-opt-level=2 72372.rs
+rustc -Zmir-opt-level=3 72372.rs

fixed/72679.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-rustc -Z mir-opt-level=2 - << EOF
+rustc -Z mir-opt-level=3 - << EOF
 
 #![cfg_attr(const_fn, feature(const_fn))]
 

fixed/73327.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-rustc -Z mir-opt-level=2 - << EOF
+rustc -Z mir-opt-level=3 - << EOF
 
 fn load<R>(_r: R) {}
 

fixed/75053.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-rustc -Zmir-opt-level=2 - << EOF
+rustc -Zmir-opt-level=3 - << EOF
 #![feature(type_alias_impl_trait)]
 
 use std::marker::PhantomData;