String performance is low and crash

hashlink :crash
neko :crash
node:17ms
hxcpp:crash
php:crash

package;

/**
* ...
* @author sonygod
*/
class StringTest
{

static function main()
{


var s = "1234567890abcdefghijklmnopqrstuvwxyz";
var t = Date.now().getTime();
var str = '';

for (i in 0...100000){
str += s;
}

trace(Date.now().getTime()-t);


}
}