Thread: error: expected specifier-qualifier-list before ‘IDirectXVideoDecoder’

Hello, I don't know much about C programming, and this is my first post here, but I was just wondering if someone could help me with a compiling issue. Here is the full error that I am getting while trying to compile FFmpeg (written in C) with mingw: CC libavcodec/dxva2.o In file included from /home - FFmpeg Make Error

I'm sorry if this is the wrong place to do this but I'm not getting any help anywhere else, and I'm pulling my hair out trying to fix this problem. Here is lines 1-40 (up to the error) of dxva2.h (the problem file).

Code:

/*
 * DXVA2 HW acceleration
 *
 * copyright (c) 2009 Laurent Aimar
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef AVCODEC_DXVA_H
#define AVCODEC_DXVA_H

#include <stdint.h>

#include <dxva2api.h>

/**
 * This structure is used to provides the necessary configurations and data
 * to the DXVA2 FFmpeg HWAccel implementation.
 *
 * The application must make it available as AVCodecContext.hwaccel_context.
 */
struct dxva_context {
    /**
     * DXVA2 decoder object
     */
    IDirectXVideoDecoder *decoder;

Does anyone have any idea what might be causing this issue and what I would need to do to fix it? I've tried defining COBJMACROS already (which I've read is the issue) but it still fails to make with that error.

Thanks a bunch.