+void Target::force_rebuild()
+{
+ if(!is_buildable())
+ throw logic_error("Target::force_rebuild");
+ mark_rebuild("Forced rebuild");
+}
+
+void Target::mark_rebuild(const string &reason)
+{
+ if(reason.empty())
+ throw invalid_argument("No reason given for rebuilding "+name);
+
+ state = REBUILD;
+ rebuild_reason = reason;
+
+ builder.get_logger().log("rebuild", format("Rebuilding %s: %s", name, reason));
+
+ signal_bubble_rebuild.emit();
+}
+
+void Target::prepare()
+{
+ if(state>PREPARING)
+ return;
+ if(state==PREPARING)
+ {
+ problems.push_back("Dependency cycle detected");
+ state = BROKEN;
+ return;
+ }
+
+ state = PREPARING;
+ if(tool)
+ tool->prepare();
+
+ find_dependencies();
+ bool broken = !problems.empty();
+
+ if(tool)
+ {
+ if(FileTarget *tool_exe = tool->get_executable())
+ add_dependency(*tool_exe);
+ broken |= !tool->get_problems().empty();
+
+ // Only check package and component problems for buildable targets
+ // XXX How to propagate nested package problems?
+ broken |= (package && !package->get_problems().empty());
+ broken |= (component && !component->get_problems().empty());
+ }
+
+ for(Dependencies::iterator i=depends.begin(); i!=depends.end(); ++i)
+ {
+ (*i)->prepare();
+ broken |= (*i)->is_broken();
+ }