def METHOD_NAME(self):
	if not (self.env['WITH_PCH'] and getattr(self, 'use', None) and getattr(self, 'compiled_tasks', None) and getattr(self.bld, 'pch_tasks', None)):
		return
	pch = None
	# find pch task, if any
	if getattr(self, 'pch_task', None):
		pch = self.pch_task
	else:
		for use in Utils.to_list(self.use):
			try:
				pch = self.bld.pch_tasks[use]
			except KeyError:
				pass
	if pch:
		for x in self.compiled_tasks:
			x.env.append_value('CXXFLAGS', self.env['CXXPCH_F'] + [pch.target])