diff --git a/guile/Makefile.am b/guile/Makefile.am
index 048c0e01..24cafc77 100644
--- a/guile/Makefile.am
+++ b/guile/Makefile.am
@@ -36,6 +36,7 @@ AM_CFLAGS=						\
 	-Wno-missing-declarations
 
 AM_CXXFLAGS=						\
+	$(XAPIAN_CXXFLAGS)                              \
 	$(ASAN_CXXFLAGS)				\
 	${WARN_CXXFLAGS}				\
 	-Wno-redundant-decls				\