diff --git a/vlib/v/builder/builder.v b/vlib/v/builder/builder.v
index 1d73dbf712..7b5f96068c 100644
--- a/vlib/v/builder/builder.v
+++ b/vlib/v/builder/builder.v
@@ -173,7 +173,7 @@ pub fn (mut b Builder) resolve_deps() {
 
 // graph of all imported modules
 pub fn (b &Builder) import_graph() &depgraph.DepGraph {
-	builtins := util.builtin_module_parts
+	builtins := util.builtin_module_parts.clone()
 	mut graph := depgraph.new_dep_graph()
 	for p in b.parsed_files {
 		mut deps := []string{}
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index 2cd848d61b..d9812378fd 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -2210,9 +2210,10 @@ pub fn (mut c Checker) assign_stmt(mut assign_stmt ast.AssignStmt) {
 			continue
 		}
 		if left_sym.kind == .array &&
-			assign_stmt.op == .assign && right_sym.kind == .array && left is ast.Ident && right is ast.Ident {
+			assign_stmt.op in [.assign, .decl_assign] && right_sym.kind == .array && left is ast.Ident &&
+			right is ast.Ident {
 			// Do not allow `a = b`, only `a = b.clone()`
-			c.warn('use `array2 = array1.clone()` instead of `array1 = array2`', assign_stmt.pos)
+			c.warn('use `array2 = array1.clone()` instead of `array2 = array1`', assign_stmt.pos)
 		}
 		left_is_ptr := left_type.is_ptr() || left_sym.is_pointer()
 		if left_is_ptr {