This sketch does not compile in the Arduino IDE

void setup() {
  // put your setup code here, to run once:

}

struct test {
  int i;
  char variable[];
};

typedef struct test test;

test t = {
  0, "hi"
};

void loop() {
  // put your main code here, to run repeatedly:

}

Arduino throws

sketch_may09a:16: error: initializer-string for array of chars is too long [-fpermissive]

 };

 ^

exit status 1
initializer-string for array of chars is too long [-fpermissive]

However compiling with g++ works just fine. How can I fix it? Or is there a principle reason why flexible array members are not supported?