diff --git a/src/hotspot/share/jfr/leakprofiler/chains/dfsClosure.cpp b/src/hotspot/share/jfr/leakprofiler/chains/dfsClosure.cpp
index 90d172247e6..1dcc5e57009 100644
--- a/src/hotspot/share/jfr/leakprofiler/chains/dfsClosure.cpp
+++ b/src/hotspot/share/jfr/leakprofiler/chains/dfsClosure.cpp
@@ -302,7 +302,7 @@ void DFSClosure::handle_objarrayoop() {
 
 void DFSClosure::drain_probe_stack() {
 
-  DEBUG_ONLY(unsigned last_depth = 0;)
+  DEBUG_ONLY(size_t last_depth = 0;)
 
   while (probe_stack_pop() && !GranularTimer::is_finished()) {