powerpc: Provide __tls_get_addr () in static libc

Since '--no-tls-optimize' is available for Power in ld, we need to provide
__tls_get_addr () in static libc in order to avoid undefined references to this
symbol when that flag is used.

	* sysdeps/powerpc/libc-tls.c: New file. Provides __tls_get_addr () in
	static libc.

ChangeLog

@@ -1,3 +1,8 @@
+2015-10-28  Carlos Eduardo Seo  <cseo@linux.vnet.ibm.com>
+
+	* sysdeps/powerpc/libc-tls.c: New file. Provides __tls_get_addr () in
+	static libc.
+
 2015-10-28  Joseph Myers  <joseph@codesourcery.com>
 
 	* sysdeps/i386/configure.ac (libc_cv_cc_avx2): Remove configure

sysdeps/powerpc/libc-tls.c

@@ -0,0 +1,32 @@
+/* Thread-local storage handling in the ELF dynamic linker.  PowerPC version.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <csu/libc-tls.c>
+#include <dl-tls.h>
+
+/* On powerpc, the linker usually optimizes code sequences used to access
+   Thread Local Storage.  However, when the user disables these optimizations
+   by passing --no-tls-optimze to the linker, we need to provide __tls_get_addr
+   in static libc in order to avoid undefined references to that symbol.  */
+
+void *
+__tls_get_addr (tls_index *ti)
+{
+  dtv_t *dtv = THREAD_DTV ();
+  return (char *) dtv[1].pointer.val + ti->ti_offset + TLS_DTV_OFFSET;
+}