diff --git a/csrc/verilator.h b/csrc/verilator.h
index b4cd0659..d5ada6c0 100644
--- a/csrc/verilator.h
+++ b/csrc/verilator.h
@@ -12,7 +12,7 @@ class VerilatedVcdFILE : public VerilatedVcdFile {
  public:
   VerilatedVcdFILE(FILE* file) : file(file) {}
   ~VerilatedVcdFILE() {}
-  bool open(const string& name) override {
+  bool open(const std::string& name) override {
     // file should already be open
     return file != NULL;
   }