diff --git a/Makefile.am b/Makefile.am
index 39c20e5..7337363 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -6,7 +6,7 @@ ACLOCAL_AMFLAGS = -Im4
 
 EXTRA_DIST = m4/gnulib-cache.m4 rpm/fuse-overlayfs.spec.template autogen.sh
 
-fuse_overlayfs_CFLAGS = -I . -I lib $(FUSE_CFLAGS)
+fuse_overlayfs_CFLAGS = -I . -I $(abs_srcdir)/lib $(FUSE_CFLAGS)
 fuse_overlayfs_LDFLAGS =
 fuse_overlayfs_LDADD = lib/libgnu.a $(FUSE_LIBS)
 fuse_overlayfs_SOURCES = main.c