diff -ura sdf3/etc/Makefile.inc sdf3.new/etc/Makefile.inc
--- sdf3/etc/Makefile.inc	2014-07-24 12:16:04.000000000 +0200
+++ sdf3.new/etc/Makefile.inc	2018-12-17 13:53:39.994552004 +0100
@@ -71,10 +71,9 @@
 RANLIB      = ranlib
 MAKE		= make
 
-CXXFLAGS    = -g -fno-tree-fre -O3 -Wall -D_GNU_SOURCE -D_$(TARGET)_ -pipe -fpic
-LDFLAGS     = 
-ARFLAGS     = cru
-MAKEFLAGS	= --no-print-directory
+CXXFLAGS   += -fno-tree-fre -fpic
+ARFLAGS     = cru
+MAKEFLAGS  += --no-print-directory
  
 OBJ         = o
 CPP         = cc