Add #![allow(..)] as necessary to get re-migrated run-pass tests compiling with clean stderr again.

Most were added mechanically.

src/test/run-pass/for-loop-while/break-value.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // run-pass
+#![allow(unreachable_code)]
 // pretty-expanded FIXME #23616
 
 fn int_id(x: isize) -> isize { return x; }

src/test/run-pass/for-loop-while/for-loop-goofiness.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // run-pass
+#![allow(dead_code)]
 
 enum BogusOption<T> {
     None,

src/test/run-pass/for-loop-while/for-loop-no-std.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // run-pass
+#![allow(unused_imports)]
 #![feature(lang_items, start, alloc)]
 #![no_std]
 

src/test/run-pass/for-loop-while/label_break_value.rs

@@ -9,6 +9,8 @@
 // except according to those terms.
 
 // run-pass
+#![allow(dead_code)]
+#![allow(unused_assignments)]
 #![feature(label_break_value)]
 
 // Test control flow to follow label_break_value semantics

src/test/run-pass/for-loop-while/liveness-assign-imm-local-after-loop.rs

@@ -9,6 +9,8 @@
 // except according to those terms.
 
 // run-pass
+#![allow(dead_code)]
+#![allow(unused_assignments)]
 // pretty-expanded FIXME #23616
 
 #![allow(unreachable_code)]

src/test/run-pass/for-loop-while/liveness-move-in-loop.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // run-pass
+#![allow(dead_code)]
 
 // pretty-expanded FIXME #23616
 

src/test/run-pass/for-loop-while/loop-break-value.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // run-pass
+#![allow(unreachable_code)]
 #![feature(never_type)]
 
 #[allow(unused)]

src/test/run-pass/for-loop-while/loop-diverges.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // run-pass
+#![allow(unused_parens)]
 // pretty-expanded FIXME #23616
 
 /* Make sure a loop{} can be the tailexpr in the body

src/test/run-pass/for-loop-while/while-label.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // run-pass
+#![allow(unreachable_code)]
 
 
 pub fn main() {

src/test/run-pass/for-loop-while/while-loop-constraints-2.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // run-pass
+#![allow(unused_assignments)]
 #![allow(unused_variables)]
 
 pub fn main() {