diff --git a/tools/debugger/gdb/gdbbuild b/tools/debugger/gdb/gdbbuild
index 1c1c9a0242..a202ebaacf 100755
--- a/tools/debugger/gdb/gdbbuild
+++ b/tools/debugger/gdb/gdbbuild
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-XENROOT=`bk root`
+XENROOT=`hg root`
 export XENROOT
 
 cd $XENROOT/tools/debugger/gdb