diff --git a/include/ChangeLog b/include/ChangeLog
index b74d05a7eeb..c27ec9c2df4 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,8 @@
+2017-11-09  Nick Clifton  <nickc@redhat.com>
+
+	* opcode/aarch64.h (aarch64_feature_set): Change type to unsigned
+	long long.
+
 2017-11-08  Tamar Christina  <tamar.christina@arm.com>
 
 	* opcode/aarch64.h:
diff --git a/include/opcode/aarch64.h b/include/opcode/aarch64.h
index 325b757b1cc..a597ebe0cbd 100644
--- a/include/opcode/aarch64.h
+++ b/include/opcode/aarch64.h
@@ -82,7 +82,7 @@ typedef uint32_t aarch64_insn;
 #define AARCH64_ANY		AARCH64_FEATURE (-1, 0)	/* Any basic core.  */
 
 /* CPU-specific features.  */
-typedef unsigned long aarch64_feature_set;
+typedef unsigned long long aarch64_feature_set;
 
 #define AARCH64_CPU_HAS_ALL_FEATURES(CPU,FEAT)	\
   ((~(CPU) & (FEAT)) == 0)