error: Deprecated pre-processor symbol

Hello. I am trying to build cluster-glue on slackware current (gcc 9.3.0). ./configure --sysconfdir=/etc --localstatedir=/var goes fine but then at build time I get the following (pasting only stderr). Any thoughts on how to solve this? I also tried version 1.0.12 + debian patches but I got same result. Thank you.

ipctest.c:1143:13: error: Deprecated pre-processor symbol, replace with  [-Werror]
 1143 |    g_main_quit(loop);
      |             ^~~~~~~~~
ipctest.c: In function ‘s_rcv_msg’:
ipctest.c:1201:13: error: Deprecated pre-processor symbol, replace with  [-Werror]
 1201 |   g_main_quit(loop);
      |             ^~~~~~~~
ipctest.c: In function ‘s_echo_msg’:
ipctest.c:1319:13: error: Deprecated pre-processor symbol, replace with  [-Werror]
 1319 |   g_main_quit(loop);
      |             ^~~~~~~~
ipctest.c: In function ‘mainloop_server’:
ipctest.c:1342:13: error: Deprecated pre-processor symbol, replace with  [-Werror]
 1342 |  loop = g_main_new(FALSE);
      |             ^~~~~~~~~~~~~~
ipctest.c:1354:13: error: Deprecated pre-processor symbol, replace with  [-Werror]
 1354 |  g_main_run(loop);
      |             ^~~~~~
ipctest.c:1355:13: error: Deprecated pre-processor symbol, replace with  [-Werror]
 1355 |  g_main_destroy(loop);
      |             ^~~~~~~~~~
ipctest.c: In function ‘mainloop_client’:
ipctest.c:1365:13: error: Deprecated pre-processor symbol, replace with  [-Werror]
 1365 |  loop = g_main_new(FALSE);
      |             ^~~~~~~~~~~~~~
ipctest.c:1370:13: error: Deprecated pre-processor symbol, replace with  [-Werror]
 1370 |  g_main_run(loop);
      |             ^~~~~~
ipctest.c:1371:13: error: Deprecated pre-processor symbol, replace with  [-Werror]
 1371 |  g_main_destroy(loop);
      |             ^~~~~~~~~~
cl_netstring.c: In function ‘msg2netstring_ll’:
cl_netstring.c:252:27: error: ‘%s’ directive writing up to 5119 bytes into a region of size between 5109 and 5118 [-Werror=format-overflow=]
  252 |   sprintf(authstring, "%d %s", authnum, authtoken);
      |                           ^~            ~~~~~~~~~
cl_netstring.c:252:3: note: ‘sprintf’ output between 3 and 5131 bytes into a destination of size 5120
  252 |   sprintf(authstring, "%d %s", authnum, authtoken);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
gmake[2]: *** [Makefile:798: cl_netstring.lo] Error 1
gmake[2]: *** Waiting for unfinished jobs....
cc1: all warnings being treated as errors
gmake[2]: *** [Makefile:784: ipctest.o] Error 1
gmake[1]: *** [Makefile:450: all-recursive] Error 1
make: *** [Makefile:487: all-recursive] Error 1

ClusterLabs / cluster-glue

error: Deprecated pre-processor symbol #24