$OpenBSD: patch-makefile,v 1.15 2012/07/10 00:07:44 sthen Exp $
--- makefile.orig	Mon Apr 23 16:28:04 2012
+++ makefile	Fri Jul  6 20:09:32 2012
@@ -145,7 +145,7 @@ ifeq ($(WIN32),)  #*nix Environments (&& cygwin)
       ifeq (,$(NOASYNCH))
         OS_CCDEFS += -DSIM_ASYNCH_IO 
       endif
-      OS_LDFLAGS += -lpthread
+      OS_LDFLAGS += -pthread
       $(info using libpthread: $(call find_lib,pthread) $(call find_include,pthread))
     endif
   endif
@@ -300,7 +300,7 @@ ifneq ($(DEBUG),)
   CFLAGS_O = -O0
   BUILD_FEATURES = - debugging support
 else
-  CFLAGS_O = -O2
+  CFLAGS_O = $(CFLAGS)
   LDFLAGS_O = 
   GCC_MAJOR_VERSION = $(firstword $(subst  ., ,$(GCC_VERSION)))
   ifneq (3,$(GCC_MAJOR_VERSION))
