diff --git a/ChangeLog b/ChangeLog
index eb51a31bc7..0748cdafe5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -42,6 +42,8 @@
 	* sysdeps/mach/hurd/i386/exc2signal.c (_hurd_exception2signal): Add
 	hidden def.
 	* mach/spin-lock.c (__mutex_unlock): Add hidden def.
+	* signal/sigaddset.c: Include <sigsetopts.h>.
+	* signal/sigdelset.c: Likewise.
 
 2018-04-03  Wilco Dijkstra  <wdijkstr@arm.com>
 
diff --git a/signal/sigaddset.c b/signal/sigaddset.c
index 7238df4738..cfb3373b13 100644
--- a/signal/sigaddset.c
+++ b/signal/sigaddset.c
@@ -17,6 +17,7 @@
 
 #include <errno.h>
 #include <signal.h>
+#include <sigsetops.h>
 #include <internal-signals.h>
 
 /* Add SIGNO to SET.  */
diff --git a/signal/sigdelset.c b/signal/sigdelset.c
index 011978cf33..52f2ce6a36 100644
--- a/signal/sigdelset.c
+++ b/signal/sigdelset.c
@@ -17,6 +17,7 @@
 
 #include <errno.h>
 #include <signal.h>
+#include <sigsetops.h>
 #include <internal-signals.h>
 
 /* Add SIGNO to SET.  */