diff --git a/src/common/StackStringStream.h b/src/common/StackStringStream.h
index 3324e7add3538..8cb48ff6fcd62 100644
--- a/src/common/StackStringStream.h
+++ b/src/common/StackStringStream.h
@@ -77,6 +77,8 @@ class StackStringBuf : public std::basic_streambuf<char>
     if (traits_type::not_eof(c)) {
       char str = traits_type::to_char_type(c);
       vec.push_back(str);
+      setp(vec.data(), vec.data() + vec.size());
+      pbump(vec.size());
       return c;
     } else {
       return traits_type::eof();