gccrs: [E0426] Use of undeclared label

Refactored error message to print more
userfriendly message and added error
code.

gcc/rust/ChangeLog:

	* resolve/rust-ast-resolve-expr.cc (ResolveExpr::visit):
	refactored message and called error function.

gcc/testsuite/ChangeLog:

	* rust/compile/undeclared_label.rs: New test for E0426.

Signed-off-by: Muhammad Mahad <[email protected]>

Author: MahadMuhammad

gcc/rust/resolve/rust-ast-resolve-expr.cc

@@ -451,8 +451,9 @@ ResolveExpr::visit (AST::BreakExpr &expr)
 				    label.get_lifetime_name ()),
 	    &resolved_node))
 	{
-	  rust_error_at (expr.get_label ().get_locus (),
-			 "failed to resolve label");
+	  rust_error_at (expr.get_label ().get_locus (), ErrorCode::E0426,
+			 "use of undeclared label %<%s%> in %<break%>",
+			 label.get_lifetime_name ().c_str ());
 	  return;
 	}
       resolver->insert_resolved_label (label.get_node_id (), resolved_node);
@@ -572,8 +573,9 @@ ResolveExpr::visit (AST::ContinueExpr &expr)
 				    label.get_lifetime_name ()),
 	    &resolved_node))
 	{
-	  rust_error_at (expr.get_label ().get_locus (),
-			 "failed to resolve label");
+	  rust_error_at (expr.get_label ().get_locus (), ErrorCode::E0426,
+			 "use of undeclared label %<%s%> in %<continue%>",
+			 label.get_lifetime_name ().c_str ());
 	  return;
 	}
       resolver->insert_resolved_label (label.get_node_id (), resolved_node);

gcc/testsuite/rust/compile/undeclared_label.rs

@@ -0,0 +1,16 @@
+// ErrorCode::E0426
+#![allow(unused)]
+fn resolve_label_continue() -> () {
+    loop {
+        continue 'a; // { dg-error "use of undeclared label .a. in .continue." }
+    }
+}
+fn resolve_label_break() -> () {
+    loop {
+        break 'crabby; // { dg-error "use of undeclared label .crabby. in .break." }
+    }
+}
+fn main() {
+    resolve_label_continue();
+    resolve_label_break();
+}