--- app/main.c.orig
+++ app/main.c
@@ -448,7 +448,8 @@
 #ifdef WIN32
 
 #else
-# ifndef DEBUG_
+  if (use_debug_handler)
+  {
   /* Handle some signals */
   signal (SIGHUP, on_signal);
   signal (SIGINT, on_signal);
@@ -466,7 +467,7 @@
   /* Handle shmem reload */
   signal( SIGUSR2, on_sig_refresh);
 # endif
-# endif /* DEBUG */
+  }
 #endif
   /* Keep the command line arguments--for use in gimp_init */
   gimp_argc = argc - 1;