diff --git a/build-aux/check.mk b/build-aux/check.mk
index 10239907..9210f626 100644
--- a/build-aux/check.mk
+++ b/build-aux/check.mk
@@ -1,20 +1,20 @@
-VALGRIND = $(VALGRIND_EXEC) -q --error-exitcode=127
+VALGRIND = $(VALGRIND_EXEC) -q --error-exitcode=127 --gen-suppressions=all
 
 MEMCHECK = $(VALGRIND) --track-fds=yes --leak-check=full --suppressions=$(abs_top_srcdir)/build-aux/knet_valgrind_memcheck.supp
 HELGRIND = $(VALGRIND) --tool=helgrind --suppressions=$(abs_top_srcdir)/build-aux/knet_valgrind_helgrind.supp
 
 check-memcheck: $(check_PROGRAMS)
 if HAS_VALGRIND
 	export KNETMEMCHECK=yes && \
 		$(MAKE) check LOG_COMPILE="libtool --mode=execute $(MEMCHECK)"
 else
 	@echo valgrind not available on this platform
 endif
 
 check-helgrind: $(check_PROGRAMS)
 if HAS_VALGRIND
 	export KNETHELGRIND=yes && \
 		$(MAKE) check LOG_COMPILE="libtool --mode=execute $(HELGRIND)"
 else
 	@echo valgrind not available on this platform
 endif