diff --git a/libcpp/ChangeLog b/libcpp/ChangeLog
index 5c4b7a09f09f..95200dacbda7 100644
--- a/libcpp/ChangeLog
+++ b/libcpp/ChangeLog
@@ -1,3 +1,9 @@
+2017-03-21  Andreas Schwab  <schwab@suse.de>
+
+	* lex.c (search_line_fast) [__ARM_NEON && __ARM_64BIT_STATE]:
+	Convert 64-bit value to boolean before passing to
+	__builtin_expect.
+
 2017-03-16  Jason Merrill  <jason@redhat.com>
 
 	* init.c (cpp_init_builtins): Update __cplusplus for C++17.
diff --git a/libcpp/lex.c b/libcpp/lex.c
index 8a8c79cde75b..a431ac8e0526 100644
--- a/libcpp/lex.c
+++ b/libcpp/lex.c
@@ -821,7 +821,7 @@ search_line_fast (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
       v = vorrq_u8 (t, vceqq_u8 (data, repl_bs));
       w = vorrq_u8 (u, vceqq_u8 (data, repl_qm));
       t = vorrq_u8 (v, w);
-      if (__builtin_expect (vpaddd_u64 ((uint64x2_t)t), 0))
+      if (__builtin_expect (vpaddd_u64 ((uint64x2_t)t) != 0, 0))
 	goto done;
     }