From: Joseph Myers <joseph@codesourcery.com>
Date: Mon, 21 Aug 2017 21:43:32 +0000 (+0000)
Subject: Fix GCC 7 build of k_standard.c.
X-Git-Tag: glibc-2.27~1102
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ea99fcd03875caf59ceda354ec8ed813bb5a5f79;p=thirdparty%2Fglibc.git

Fix GCC 7 build of k_standard.c.

This patch adds a default case to k_standard.c that calls
__builtin_unreachable, to avoid an uninitialized variable error from
GCC 7 (reported in
<https://sourceware.org/ml/libc-alpha/2017-08/msg01012.html>).

Tested for x86_64 (with GCC 7).

	* sysdeps/ieee754/k_standard.c (__kernel_standard): Add default
	case calling __builtin_unreachable.
---

diff --git a/ChangeLog b/ChangeLog
index 3d2afd95efa..bf3e893f259 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2017-08-21  Joseph Myers  <joseph@codesourcery.com>
+
+	* sysdeps/ieee754/k_standard.c (__kernel_standard): Add default
+	case calling __builtin_unreachable.
+
 2017-08-21  Adhemerval Zanella  <adhemerval.zanella@linaro.org>
 
 	* libio/ioopen.c (_IO_waitpid): Replace waitpid_not_cancel with
diff --git a/sysdeps/ieee754/k_standard.c b/sysdeps/ieee754/k_standard.c
index 0a0201f1d50..8f906bd604d 100644
--- a/sysdeps/ieee754/k_standard.c
+++ b/sysdeps/ieee754/k_standard.c
@@ -939,6 +939,9 @@ __kernel_standard(double x, double y, int type)
 		break;
 
 		/* #### Last used is 50/150/250 ### */
+
+	    default:
+		__builtin_unreachable ();
 	}
 	return exc.retval;
 }