diff --git a/Makefile b/Makefile
index fe81845d..9ea95bdd 100644
--- a/Makefile
+++ b/Makefile
@@ -31,3 +31,14 @@ SUBDIRS = inst/pre \
 
 include $(TOPDIR)/make/proj.mk
 include $(TOPDIR)/make/topdir.mk
+
+define symversion
+nm $(LIB_A) | sed '/^[0-9]\{8\} T / !d; s/^[0-9]\{8\} T //' | sort -u
+endef
+
+SYMBOLS: $(LIB_A)
+	$(symversion) > $@.tmp
+	mv $@.tmp $@
+
+check_symversion:
+	$(symversion) | diff SYMBOLS - | sed '/^</ !d'