Yep, that looks like it did the trick.
What else I noticed, after I posted, is that it only affects some files.  Which is even stranger.  Thinking it might have something to do with character sets, I tried recreating the same file by copy/paste from gedit but that didn't improve things.
Another possibility is that there was some kind of syntax that was causing the problem, but I'm not sure.  I pasted the code of the file in question below:
/*
 *  wb_fsm_state_status.h
 *  gusimplewhiteboard / clfsm
 *
 *  Created by Dimitri Joukoff on 15/10/2014.
 *  Copyright (c) 2013, 2014 Rene Hexel. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above
 *    copyright notice, this list of conditions and the following
 *    disclaimer in the documentation and/or other materials
 *    provided with the distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgement:
 *
 *        This product includes software developed by Rene Hexel.
 *
 * 4. Neither the name of the author nor the names of contributors
 *    may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * -----------------------------------------------------------------------
 * This program is free software; you can redistribute it and/or
 * modify it under the above terms or under the terms of the GNU
 * General Public License as published by the Free Software Foundation;
 * either version 2 of the License, or (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see http://www.gnu.org/licenses/
 * or write to the Free Software Foundation, Inc., 51 Franklin Street,
 * Fifth Floor, Boston, MA  02110-1301, USA.
 *
 */
#ifndef gusimplewhiteboard_wb_fsm_state_status_h
#define gusimplewhiteboard_wb_fsm_state_status_h
#include <gu_util.h>
#include "gusimplewhiteboard.h"
#define STATE_BYTE_SIZE     (sizeof(gu_simple_message))
#define INVALDMACHINE       ~0
#define STATESTATUS_SET_STATE(s, machineID, state)   ((s)->_fsms[machineID] = state)
#define STATESTATUS_GET_STATE(s, machineID)    ((s)->_fsms[machineID])
struct wb_fsm_state_status
{
    ARRAY_PROPERTY(uint8_t, fsms, STATE_BYTE_SIZE)
#ifdef __cplusplus
    wb_fsm_state_status()
    {
        memset(this, INVALDMACHINE, sizeof(*this));
    }
#endif
};
#endif // gusimplewhiteboard_wb_fsm_state_status_h