Get rid of the DEFS variable.  The only thing this was used for was to
pass -DHAVE_CONFIG_H to CC, and that symbol isn't used any more.
diff --git a/Makefile.pre.in b/Makefile.pre.in
index ef1a2d3..e77a037 100644
--- a/Makefile.pre.in
+++ b/Makefile.pre.in
@@ -54,9 +54,8 @@
 
 # Compiler options
 OPT=		@OPT@
-DEFS=		@DEFS@
 CFLAGS=		$(OPT)
-CPPFLAGS=	-I. -I$(srcdir)/Include $(DEFS)
+CPPFLAGS=	-I. -I$(srcdir)/Include
 LDFLAGS=	@LDFLAGS@
 LDLAST=		@LDLAST@
 SGI_ABI=	@SGI_ABI@