Index: wafadmin/Scan.py===================================================================--- wafadmin/Scan.py (revision 1327)+++ wafadmin/Scan.py (working copy)@@ -94,7 +94,12 @@ for dep in lst: if not dep.m_name in seen: add_node_sig(dep)- m.update(tree.m_tstamp_variants[variant][node])+ try:+ m.update(tree.m_tstamp_variants[variant][node])+ except KeyError:+ sig = Params.h_file(node.bldpath(env))+ tree.m_tstamp_variants[variant][node] = sig+ m.update(sig) # add the signatures of the input nodes for node in task.m_inputs: add_node_sig(node)