gp.preemptShrink = true
	}

	var state stackScanState
	state.stack = gp.stack

	if stackTraceDebug {
		println("stack trace goroutine", gp.goid)
	}

	if debugScanConservative && gp.asyncSafePoint {
		print("scanning async preempted goroutine ", gp.goid, " stack [", hex(gp.stack.lo), ",", hex(gp.stack.hi), ")\n")
	}

	// Scan the saved context register. This is effectively a live

	// concurrentSweep is a debug flag. Disabling this flag
	// ensures all spans are swept while the world is stopped.
	concurrentSweep = true

	// debugScanConservative enables debug logging for stack
	// frames that are scanned conservatively.
	debugScanConservative = false

	// sweepMinHeapDistance is a lower bound on the heap distance
	// (in bytes) reserved for concurrent sweeping between GC
	// cycles.