diff --git a/src/test/javacompat.cpp b/src/test/javacompat.cpp
index 08e77de..1f34aad 100644
--- a/src/test/javacompat.cpp
+++ b/src/test/javacompat.cpp
@@ -87,7 +87,7 @@ int main(){
 
     std::vector<uint8_t> data = JavaCompat::exportJavaString(normalString).value;
     std::string exportedString = std::string();
-    for(int i=0; i<data.size(); i++){
+    for(int i=0; i<(int) data.size(); i++){
         exportedString.push_back(data[i]);
     }