diff --git a/config/Rules.am b/config/Rules.am
index 0b41ec4605..7c5d3283fe 100644
--- a/config/Rules.am
+++ b/config/Rules.am
@@ -9,5 +9,6 @@
 DEFAULT_INCLUDES = -include ${top_builddir}/spl_config.h
 
 AM_LIBTOOLFLAGS = --silent
+AM_CPPFLAGS = -D__USE_LARGEFILE64
 AM_CFLAGS  = -Wall -Wshadow -Wstrict-prototypes -fno-strict-aliasing
-AM_CFLAGS += -D__USE_LARGEFILE64 ${DEBUG_CFLAGS}
+AM_CFLAGS += ${DEBUG_CFLAGS}