Broken code

fft.cpp

#include <cstdint>
#include <iostream>
#include <iomanip>
#include "fft.h"

FFT::FFT(const std::string& filename)
	: file(filename, std::ifstream::binary)
{
	int32_t chunk_id;
	file.read(reinterpret_cast<char*>(&chunk_id), 4);

	int32_t file_size;
	file.read(reinterpret_cast<char*>(&file_size), 4);

	int32_t type;
	file.read(reinterpret_cast<char*>(&type), 4); // should be WAVE

	int32_t format;
	file.read(reinterpret_cast<char*>(&format),4); // should be fmt\0

	int32_t format_length;
	file.read(reinterpret_cast<char*>(&format_length), 4);

	int16_t wave_type;
	file.read(reinterpret_cast<char*>(&wave_type), 2);

	int16_t channels;
	file.read(reinterpret_cast<char*>(&channels), 2);

	int32_t sample_rate;
	file.read(reinterpret_cast<char*>(&sample_rate), 4);

	int32_t byte_rate;
	file.read(reinterpret_cast<char*>(&byte_rate), 4);

	int16_t align;
	file.read(reinterpret_cast<char*>(&align), 2);

	int16_t bits_per_sample;
	file.read(reinterpret_cast<char*>(&bits_per_sample), 2);

	int32_t data_length;
	file.read(reinterpret_cast<char*>(&data_length), 4);

	int16_t data[data_length];
	file.read(reinterpret_cast<char*>(&data), data_length * 2);
}

fft.h

#ifndef FFT_FFT_H
#define FFT_FFT_H

#include <fstream>
#include <string>

class FFT {
public:
	FFT(const std::string& filename);

private:
	std::fstream file;
};

#endif //FFT_FFT_H