This class helps ignore leaks in some block:

#include "DeleakerClientApi.h"

Singleton* _singleton;

void f()
	// This is a block, allocations of which are not being monitored by Deleaker
	// because of DeleakerClientApi::CIgnoreLeaks instance
		DeleakerClientApi::CIgnoreLeaks IgnoreLeaks;

		_singleton = new Singleton(); // I don't want to view this leak in the Deleaker report

Also look at DeleakerClientApi_IgnoreLeaks. CIgnoreLeaks just calls DeleakerClientApi_IgnoreLeaks(TRUE) in constructor, and DeleakerClientApi_IgnoreLeaks(FALSE) in desctructor.