diff --git a/src/debugger/DebuggerParser.cxx b/src/debugger/DebuggerParser.cxx
index b8e15ff90..73026a213 100644
--- a/src/debugger/DebuggerParser.cxx
+++ b/src/debugger/DebuggerParser.cxx
@@ -108,7 +108,7 @@ string DebuggerParser::run(const string& command)
   getArgs(command, verb);
   commandResult.str("");
 
-  for(int i = 0; i < commands.size(); ++i)
+  for(int i = 0; i < int(commands.size()); ++i)
   {
     if(BSPF::equalsIgnoreCase(verb, commands[i].cmdString))
     {