Index: trunk/Mars/macros/rootlogon.C
===================================================================
--- trunk/Mars/macros/rootlogon.C	(revision 11428)
+++ trunk/Mars/macros/rootlogon.C	(revision 11429)
@@ -177,5 +177,5 @@
     if (TString("linux")==gSystem->GetBuildArch())
     {
-        TString options = " -O3 -pipe -Wall -Woverloaded-virtual -fno-exceptions -fPIC ";
+        TString options = " -O3 -D__MARS__ -pipe -Wall -Woverloaded-virtual -fno-exceptions -fPIC ";
 
         TString s = "cd $BuildDir ; ";