Strongest SSID example crash

application.cpp

/*
This will give a hard fault firmware crash. 
The crash can be prevented by adding a delay of around 800ms (I've tested 100ms and 500ms and it crashes the same). 
*/


#include "application.h"

//SYSTEM_THREAD(ENABLED);
SYSTEM_MODE(MANUAL);

class FindStrongestSSID
{
    char strongest_ssid[33];
    int strongest_rssi;

    // This is the callback passed to WiFi.scan()
    // It makes the call on the `self` instance - to go from a static
    // member function to an instance member function.
    static void handle_ap(WiFiAccessPoint* wap, FindStrongestSSID* self)
    {
        self->next(*wap);
    }

    // determine if this AP is stronger than the strongest seen so far
    void next(WiFiAccessPoint& ap)
    {
        if ((ap.rssi < 0) && (ap.rssi > strongest_rssi)) {
            strongest_rssi = ap.rssi;

            strcpy(strongest_ssid, ap.ssid);
        }
    }

public:

    /**
     * Scan Wi-Fi Access Points and retrieve the strongest one.
     */
    const char* scan()
    {
        // initialize data
        strongest_rssi = 0;
        strongest_ssid[0] = 0;
        // perform the scan
        WiFi.scan(handle_ap, this);
        return strongest_ssid;
    }
};

// Now use the class
FindStrongestSSID strongestFinder;
const char* ssid;

void setup() {
  Serial.begin(57600);
	delay(5000);
	Serial.println("hi");
	Particle.connect();
	Serial.println("hi again");

	// adding a delay to the end seems to solve the crash
	//delay(800);

}

void loop() {

	ssid = strongestFinder.scan();

	//Serial.print("strongest ssid : ");
	//Serial.println(ssid);
	//delay(1000);

}