--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/config/nios2/linux.h	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,50 @@
+/* Definitions of target support for Altera Nios II systems
+   running GNU/Linux with ELF format.
+   Copyright (C) 2012-2017 Free Software Foundation, Inc.
+   Contributed by Mentor Graphics, Inc.
+
+   This file is part of GCC.
+
+   GCC is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3, or (at your
+   option) any later version.
+
+   GCC 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 General Public
+   License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with GCC; see the file COPYING3.  If not see
+   <http://www.gnu.org/licenses/>.  */
+
+#define TARGET_OS_CPP_BUILTINS()                \
+  do                                            \
+    {                                           \
+      GNU_USER_TARGET_OS_CPP_BUILTINS();           \
+    }                                           \
+  while (0)
+
+#undef CPP_SPEC
+#define CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_REENTRANT}"
+
+#define GLIBC_DYNAMIC_LINKER "/lib/ld-linux-nios2.so.1"
+
+#undef LINK_SPEC
+#define LINK_SPEC LINK_SPEC_ENDIAN \
+ "%{shared:-shared} \
+  %{!shared: \
+    %{!static: \
+      %{rdynamic:-export-dynamic} \
+      -dynamic-linker " GNU_USER_DYNAMIC_LINKER "} \
+    %{static:-static}}"
+
+/* This toolchain implements the ABI for Linux Systems documented in the
+   Nios II Processor Reference Handbook.  */
+#define TARGET_LINUX_ABI 1
+
+/* For Linux, we have access to kernel support for atomic operations,
+   add initialization for __sync_* builtins.  */
+#undef TARGET_INIT_LIBFUNCS
+#define TARGET_INIT_LIBFUNCS nios2_init_libfuncs