diff --git a/frontends/systemverilog/uhdm_ast.cc b/frontends/systemverilog/uhdm_ast.cc
index 521137e54..1c16c8dbc 100644
--- a/frontends/systemverilog/uhdm_ast.cc
+++ b/frontends/systemverilog/uhdm_ast.cc
@@ -1031,6 +1031,8 @@ static AST::AstNode *convert_dot(AST::AstNode *wire_node, AST::AstNode *node, AS
             // offset = size * n
             auto index = dot->children.at(0)->children.at(0);
             auto move_offset = new AST::AstNode(AST::AST_MUL, target_size, index->clone());
+            delete expanded->children[0];
+            delete expanded->children[1];
             expanded->children[0] = new AST::AstNode(AST::AST_ADD, move_offset, target_l->clone());
             expanded->children[1] = new AST::AstNode(AST::AST_ADD, move_offset->clone(), target_r->clone());
             return expanded;