diff --git a/tests/cefclient/browser/osr_ime_handler_win.cc b/tests/cefclient/browser/osr_ime_handler_win.cc
index b497deb17..6e8546fcd 100644
--- a/tests/cefclient/browser/osr_ime_handler_win.cc
+++ b/tests/cefclient/browser/osr_ime_handler_win.cc
@@ -74,7 +74,7 @@ void GetCompositionUnderlines(
     ::ImmGetCompositionString(imc, GCS_COMPCLAUSE, &clause_data[0],
                               clause_size);
     for (int i = 0; i < clause_length - 1; ++i) {
-      cef_composition_underline_t underline;
+      cef_composition_underline_t underline = {};
       underline.range.from = clause_data[i];
       underline.range.to = clause_data[i + 1];
       underline.color = ColorUNDERLINE;