Error when using named argument on trailing macro body expansion #2139.

releasenotes.md

@@ -31,6 +31,7 @@
 - Incorrect parsing of ad hoc generic types, like `Foo{int}****` #2140.
 - $define did not correctly handle generic types #2140.
 - Incorrect parsing of call attributes #2144.
+- Error when using named argument on trailing macro body expansion #2139.
 
 ### Stdlib changes
 - Added `String.quick_ztr` and `String.is_zstr`

src/compiler/sema_expr.c

@@ -1290,6 +1290,11 @@ static bool sema_analyse_parameter(SemaContext *context, Expr *arg, Decl *param,
 	{
 		case VARDECL_PARAM:
 			// foo
+			if (arg->expr_kind == EXPR_NAMED_ARGUMENT)
+			{
+				// This only happens in body arguments
+				RETURN_SEMA_ERROR(arg, "Named arguments are not supported for body parameters.");
+			}
 			if (!sema_analyse_expr_rhs(context, type, arg, true, no_match_ref, false)) return false;
 			if (IS_OPTIONAL(arg)) *optional_ref = true;
 			switch (sema_resolve_storage_type(context, arg->type))

test/test_suite/macros/trailing_body_named.c3

@@ -0,0 +1,9 @@
+macro @foo(; @body(int arg))
+{
+	@body(arg: 0); // #error: Named arguments are not supported for body parameters
+}
+
+fn void main()
+{
+	@foo(; int arg) {};
+}