diff --git a/offline_compiler/decoder/helper.cpp b/offline_compiler/decoder/helper.cpp
index 0599fb4aa1..15aafec0b7 100644
--- a/offline_compiler/decoder/helper.cpp
+++ b/offline_compiler/decoder/helper.cpp
@@ -20,7 +20,7 @@ void addSlash(std::string &path) {
     if (!path.empty()) {
         auto lastChar = *path.rbegin();
         if ((lastChar != '/') && (lastChar != '\\')) {
-            path += '/';
+            path.append("/");
         }
     }
 }