Added detailed error code explanation for issue E0696 in Rust compiler.

src/librustc_error_codes/error_codes.rs

@@ -386,6 +386,7 @@ E0691: include_str!("./error_codes/E0691.md"),
 E0692: include_str!("./error_codes/E0692.md"),
 E0693: include_str!("./error_codes/E0693.md"),
 E0695: include_str!("./error_codes/E0695.md"),
+E0696: include_str!("./error_codes/E0696.md"),
 E0697: include_str!("./error_codes/E0697.md"),
 E0698: include_str!("./error_codes/E0698.md"),
 E0699: include_str!("./error_codes/E0699.md"),
@@ -602,7 +603,6 @@ E0751: include_str!("./error_codes/E0751.md"),
     E0687, // in-band lifetimes cannot be used in `fn`/`Fn` syntax
     E0688, // in-band lifetimes cannot be mixed with explicit lifetime binders
 //  E0694, // an unknown tool name found in scoped attributes
-    E0696, // `continue` pointing to a labeled block
 //  E0702, // replaced with a generic attribute input check
 //  E0707, // multiple elided lifetimes used in arguments of `async fn`
 //  E0709, // multiple different lifetimes used in arguments of `async fn`

src/librustc_error_codes/error_codes/E0696.md

@@ -0,0 +1,49 @@
+A function is using `continue` keyword incorrectly.
+
+Erroneous code example:
+
+```compile_fail,E0696
+fn continue_simple() {
+    'b: {
+        continue; // error!
+    }
+}
+fn continue_labeled() {
+    'b: {
+        continue 'b; // error!
+    }
+}
+fn continue_crossing() {
+    loop {
+        'b: {
+            continue; // error!
+        }
+    }
+}
+```
+
+Here we have used the `continue` keyword incorrectly. As we
+have seen above that `continue` pointing to a labeled block.
+
+To fix this we have to use the labeled block properly.
+For example:
+
+```
+fn continue_simple() {
+    'b: loop {
+        continue ; // ok!
+    }
+}
+fn continue_labeled() {
+    'b: loop {
+        continue 'b; // ok!
+    }
+}
+fn continue_crossing() {
+    loop {
+        'b: loop {
+            continue; // ok!
+        }
+    }
+}
+```

src/test/ui/label/label_break_value_continue.stderr

@@ -21,4 +21,5 @@ LL |             continue;
 
 error: aborting due to 3 previous errors
 
-For more information about this error, try `rustc --explain E0695`.
+Some errors have detailed explanations: E0695, E0696.
+For more information about an error, try `rustc --explain E0695`.