--- src/lib/VSDContentCollector.cpp
+++ src/lib/VSDContentCollector.cpp
@@ -3220,7 +3220,7 @@
     }
     if (U_SUCCESS(status) && conv)
     {
-      const auto *src = (const char *)&characters[0];
+      const auto *src = (const char *)characters.data();
       const char *srcLimit = (const char *)src + characters.size();
       while (src < srcLimit)
       {