$ git log -1
commit 08435a6ac07f6437c707bf281a0c5b8c96a4fd2e
Author: Sean Davis <smd.seandavis@gmail.com>
Date:   Sat Aug 20 18:02:46 2016 -0400

    Resolve gdk_threads_* deprecated warnings, thanks f2404!
    https://github.com/xfce-mirror/exo/pull/5

$ make
make  all-recursive
make[1]: Entering directory '/tmp/exo'
Making all in exo
make[2]: Entering directory '/tmp/exo/exo'
make  all-am
make[3]: Entering directory '/tmp/exo/exo'
  CC       libexo_1_la-exo-job.lo
exo-job.c: In function ‘exo_job_emit_valist’:
exo-job.c:398:3: error: ‘g_io_scheduler_job_send_to_mainloop’ is deprecated: Use 'g_main_context_invoke' instead [-Werror=deprecated-declarations]
   g_io_scheduler_job_send_to_mainloop (job->priv->scheduler_job,
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/glib-2.0/gio/gio.h:89:0,
                 from exo-job.c:28:
/usr/include/glib-2.0/gio/gioscheduler.h:42:10: note: declared here
 gboolean g_io_scheduler_job_send_to_mainloop       (GIOSchedulerJob     *job,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
exo-job.c: In function ‘IA__exo_job_launch’:
exo-job.c:477:3: error: ‘g_io_scheduler_push_job’ is deprecated: Use '"GThreadPool or g_task_run_in_thread"' instead [-Werror=deprecated-declarations]
   g_io_scheduler_push_job (exo_job_scheduler_job_func, g_object_ref (job),
   ^~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/glib-2.0/gio/gio.h:89:0,
                 from exo-job.c:28:
/usr/include/glib-2.0/gio/gioscheduler.h:34:10: note: declared here
 void     g_io_scheduler_push_job                   (GIOSchedulerJobFunc  job_func,
          ^~~~~~~~~~~~~~~~~~~~~~~
exo-job.c: In function ‘IA__exo_job_send_to_mainloop’:
exo-job.c:673:3: error: ‘g_io_scheduler_job_send_to_mainloop’ is deprecated: Use 'g_main_context_invoke' instead [-Werror=deprecated-declarations]
   return g_io_scheduler_job_send_to_mainloop (job->priv->scheduler_job, func, user_data,
   ^~~~~~
In file included from /usr/include/glib-2.0/gio/gio.h:89:0,
                 from exo-job.c:28:
/usr/include/glib-2.0/gio/gioscheduler.h:42:10: note: declared here
 gboolean g_io_scheduler_job_send_to_mainloop       (GIOSchedulerJob     *job,
          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
Makefile:1157: recipe for target 'libexo_1_la-exo-job.lo' failed
make[3]: *** [libexo_1_la-exo-job.lo] Error 1
make[3]: Leaving directory '/tmp/exo/exo'
Makefile:892: recipe for target 'all' failed
make[2]: *** [all] Error 2
make[2]: Leaving directory '/tmp/exo/exo'
Makefile:532: recipe for target 'all-recursive' failed
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory '/tmp/exo'
Makefile:464: recipe for target 'all' failed
make: *** [all] Error 2

$ rpm --query --file /usr/include/glib-2.0/gio/gioscheduler.h
glib2-devel-2.48.2-1.fc24.x86_64