--- fbreader-0.99.4/makefiles/config.mk.optflags	2012-11-30 04:41:25.000000000 -0800
+++ fbreader-0.99.4/makefiles/config.mk	2018-08-28 20:53:52.708604263 -0700
@@ -26,7 +26,7 @@
 endif
 
 ifeq "$(TARGET_STATUS)" "release"
-	CFLAGS += -O3
+	CFLAGS += $(RPM_OPT_FLAGS) -Wno-narrowing
 endif
 ifeq "$(TARGET_STATUS)" "debug"
 	CFLAGS += -O0 -g