diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index c53df411fd8..7dcbe7e2c2e 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2019-08-01  Tom Tromey  <tromey@adacore.com>
+
+	* ia64-libunwind-tdep.h (struct libunwind_descr): Include
+	gdbarch.h.
+
 2019-08-01  Christian Biesinger  <cbiesinger@google.com>
 
 	* s12z-tdep.c: Fix include path for s12z-opc.h.
diff --git a/gdb/ia64-libunwind-tdep.h b/gdb/ia64-libunwind-tdep.h
index 3ad3d44f367..06a8d5463d7 100644
--- a/gdb/ia64-libunwind-tdep.h
+++ b/gdb/ia64-libunwind-tdep.h
@@ -36,6 +36,8 @@ struct frame_unwind;
    running on.  */
 #include "libunwind-ia64.h"
 
+#include "gdbarch.h"
+
 struct libunwind_descr
 {
   int (*gdb2uw) (int);