diff --git a/llarp/router_contact.cpp b/llarp/router_contact.cpp
index 3e5ac72bb..af731b117 100644
--- a/llarp/router_contact.cpp
+++ b/llarp/router_contact.cpp
@@ -338,7 +338,7 @@ namespace llarp
     }
     f.seekg(0, std::ios::end);
     auto l = f.tellg();
-    if(l > sizeof(tmp))
+    if(l > static_cast< std::streamoff >(sizeof tmp))
       return false;
     f.seekg(0, std::ios::beg);
     f.read((char *)tmp, l);