gccrs: Fix issue with parsing unsafe block expression statements

gcc/rust/ChangeLog:

	* parse/rust-parse-impl.h
	(Parser::parse_stmt): Handle unsafe expression statements.

gcc/testsuite/ChangeLog:

	* rust/compile/issue-1422.rs: New test.

Signed-off-by: Owen Avery <powerboat9.gamer@gmail.com>

gcc/rust/parse/rust-parse-impl.h

@@ -6131,7 +6131,15 @@ Parser<ManagedTokenSource>::parse_stmt (ParseRestrictions restrictions)
       /* if any of these (should be all possible VisItem prefixes), parse a
        * VisItem can't parse item because would require reparsing outer
        * attributes */
-      return parse_vis_item (std::move (outer_attrs));
+      // may also be unsafe block
+      if (lexer.peek_token (1)->get_id () == LEFT_CURLY)
+	{
+	  return parse_expr_stmt (std::move (outer_attrs), restrictions);
+	}
+      else
+	{
+	  return parse_vis_item (std::move (outer_attrs));
+	}
       break;
     case SUPER:
     case SELF:

gcc/testsuite/rust/compile/issue-1422.rs

@@ -0,0 +1,7 @@
+macro_rules! test {
+    () => { unsafe {} };
+}
+
+fn main() {
+    test!();
+}