diff --git a/src/mem/probes/mem_footprint.hh b/src/mem/probes/mem_footprint.hh
index 821d61ae1f..35c03cc798 100644
--- a/src/mem/probes/mem_footprint.hh
+++ b/src/mem/probes/mem_footprint.hh
@@ -41,7 +41,7 @@
 #ifndef __MEM_PROBES_MEM_FOOTPRINT_HH__
 #define __MEM_PROBES_MEM_FOOTPRINT_HH__
 
-#include <unordered_map>
+#include <unordered_set>
 
 #include "base/callback.hh"
 #include "mem/packet.hh"