--- ./Makefile.rules.orig	2017-02-13 21:51:51.000000000 +0200
+++ ./Makefile.rules	2017-03-20 14:33:51.403195000 +0200
@@ -59,7 +59,7 @@
     CMD_PREFIX=
 endif
 
-OPTIMIZE?=-O3
+OPTIMIZE?=-O2
 ifneq ($(findstring darwin,$(OSARCH)),)
   ifeq ($(shell if test `/usr/bin/sw_vers -productVersion | cut -c4` -gt 5; then echo 6; else echo 0; fi),6)
     # Snow Leopard/Lion has an issue with this optimization flag on large files (like chan_sip)