Consistently warn unreachable subpatterns

tests/ui/or-patterns/exhaustiveness-unreachable-pattern.rs

@@ -162,12 +162,14 @@ fn main() {
 }
 
 fn unreachable_in_param((_ | (_, _)): (bool, bool)) {}
+//~^ ERROR unreachable
 
 fn unreachable_in_binding() {
     let bool_pair = (true, true);
     let bool_option = Some(true);
 
     let (_ | (_, _)) = bool_pair;
+    //~^ ERROR unreachable
     for (_ | (_, _)) in [bool_pair] {}
     //~^ ERROR unreachable
 

tests/ui/or-patterns/exhaustiveness-unreachable-pattern.stderr

@@ -184,29 +184,41 @@ error: unreachable pattern
 LL |             | (y, x) => {}
    |               ^^^^^^
 
+error: unreachable pattern
+  --> $DIR/exhaustiveness-unreachable-pattern.rs:164:30
+   |
+LL | fn unreachable_in_param((_ | (_, _)): (bool, bool)) {}
+   |                              ^^^^^^
+
 error: unreachable pattern
   --> $DIR/exhaustiveness-unreachable-pattern.rs:171:14
    |
+LL |     let (_ | (_, _)) = bool_pair;
+   |              ^^^^^^
+
+error: unreachable pattern
+  --> $DIR/exhaustiveness-unreachable-pattern.rs:173:14
+   |
 LL |     for (_ | (_, _)) in [bool_pair] {}
    |              ^^^^^^
 
 error: unreachable pattern
-  --> $DIR/exhaustiveness-unreachable-pattern.rs:174:20
+  --> $DIR/exhaustiveness-unreachable-pattern.rs:176:20
    |
 LL |     let (Some(_) | Some(true)) = bool_option else { return };
    |                    ^^^^^^^^^^
 
 error: unreachable pattern
-  --> $DIR/exhaustiveness-unreachable-pattern.rs:176:22
+  --> $DIR/exhaustiveness-unreachable-pattern.rs:178:22
    |
 LL |     if let Some(_) | Some(true) = bool_option {}
    |                      ^^^^^^^^^^
 
 error: unreachable pattern
-  --> $DIR/exhaustiveness-unreachable-pattern.rs:178:25
+  --> $DIR/exhaustiveness-unreachable-pattern.rs:180:25
    |
 LL |     while let Some(_) | Some(true) = bool_option {}
    |                         ^^^^^^^^^^
 
-error: aborting due to 33 previous errors
+error: aborting due to 35 previous errors
 

tests/ui/rfcs/rfc-0000-never_patterns/unreachable.exh_pats.stderr

@@ -11,22 +11,34 @@ LL | #![deny(unreachable_patterns)]
    |         ^^^^^^^^^^^^^^^^^^^^
 
 error: unreachable pattern
-  --> $DIR/unreachable.rs:21:12
+  --> $DIR/unreachable.rs:20:19
+   |
+LL |     let (Ok(_x) | Err(!)) = res_void;
+   |                   ^^^^^^
+
+error: unreachable pattern
+  --> $DIR/unreachable.rs:22:12
    |
 LL |     if let Err(!) = res_void {}
    |            ^^^^^^
 
 error: unreachable pattern
-  --> $DIR/unreachable.rs:23:24
+  --> $DIR/unreachable.rs:24:24
    |
 LL |     if let (Ok(true) | Err(!)) = res_void {}
    |                        ^^^^^^
 
 error: unreachable pattern
-  --> $DIR/unreachable.rs:25:23
+  --> $DIR/unreachable.rs:26:23
    |
 LL |     for (Ok(mut _x) | Err(!)) in [res_void] {}
    |                       ^^^^^^
 
-error: aborting due to 4 previous errors
+error: unreachable pattern
+  --> $DIR/unreachable.rs:30:18
+   |
+LL | fn foo((Ok(_x) | Err(!)): Result<bool, Void>) {}
+   |                  ^^^^^^
+
+error: aborting due to 6 previous errors
 

tests/ui/rfcs/rfc-0000-never_patterns/unreachable.rs

@@ -18,6 +18,7 @@ fn main() {
         //[exh_pats]~^ ERROR unreachable
     }
     let (Ok(_x) | Err(!)) = res_void;
+    //[exh_pats]~^ ERROR unreachable
     if let Err(!) = res_void {}
     //[exh_pats]~^ ERROR unreachable
     if let (Ok(true) | Err(!)) = res_void {}
@@ -27,3 +28,4 @@ fn main() {
 }
 
 fn foo((Ok(_x) | Err(!)): Result<bool, Void>) {}
+//[exh_pats]~^ ERROR unreachable

tests/ui/unsafe/union_destructure.rs

@@ -1,4 +1,5 @@
 // run-pass
+#![allow(unreachable_patterns)]
 
 #[derive(Copy, Clone)]
 #[allow(dead_code)]