diff -urN fontforge-20170731.old/fontforge/Makefile.am fontforge-20170731/fontforge/Makefile.am
--- fontforge-20170731.old/fontforge/Makefile.am	2017-07-31 03:19:01.000000000 +0530
+++ fontforge-20170731/fontforge/Makefile.am	2019-06-01 23:35:57.644257299 +0530
@@ -192,7 +192,7 @@
 # without optimization.
 splinerefigure.lo: $(srcdir)/splinerefigure.c $(srcdir)/splinefont.h
 	$(LIBTOOL) --mode=compile $(CC) $(RAW_COMPILE_PLATFORM_CFLAGS) -g -c -o \
-		splinerefigure.lo $(AM_CPPFLAGS) $(srcdir)/splinerefigure.c
+		splinerefigure.lo $(AM_CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) $(srcdir)/splinerefigure.c
 
 #--------------------------------------------------------------------------
 EXTRA_DIST = generate_codepoint_selector.py threaddummy.c