ARC: Add multilib support for Linux in GCC

We never bothered to build multilibbed Linux toolchains for ARC
and so we ended-up with no support of multilib for arc*-*-linux-*
targets in GCC. That is now fixed in upstream by the following commit:
https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=0eacfbcb2bf1834294f468a2bb41fe5d5e8d3883

Once the fix mentioned above is applied on top of GCC 8.1.0 we may easily build
multilibbed uClibc toolchain for ARC.

Note sice Glibc port for ARC is still in review process we cannot build any Glibc
toolchains for ARC with pure upstream components, for that we eiter need Glibc
sources from our Github repo or apply a set of patches on top of Glibc 2.27 - we'll
try to address this later though.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

1 files changed, 76 insertions, 0 deletions

diff --git a/packages/gcc/8.1.0/0019-ARC-Add-multilib-support-for-linux-targets.patch b/packages/gcc/8.1.0/0019-ARC-Add-multilib-support-for-linux-targets.patch
new file mode 100644
index 0000000..6151067
--- /dev/null
+++ b/packages/gcc/8.1.0/0019-ARC-Add-multilib-support-for-linux-targets.patch
@@ -0,0 +1,76 @@
+From 0eacfbcb2bf1834294f468a2bb41fe5d5e8d3883 Mon Sep 17 00:00:00 2001
+From: claziss <claziss@138bc75d-0d04-0410-961f-82ee72b054a4>
+Date: Mon, 21 May 2018 09:56:57 +0000
+Subject: [PATCH] [ARC] Add multilib support for linux targets
+
+We used to build baremetal (AKA Elf32) multilibbed toolchains for years
+now but never made that for Linux targets since there were problems with
+uClibc n multilib setup. Now with help of Crosstool-NG it is finally
+possible to create uClibc-based multilibbed toolchains and so we add
+relevant CPUs for multilib in case of configuration for "arc*-*-linux*".
+
+This will be essentially useful for glibc-based multilibbbed toolchains
+in the future.
+
+gcc/
+2018-05-16  Alexey Brodkin <abrodkin@synopsys.com>
+
+        * config.gcc: Add arc/t-multilib-linux to tmake_file for
+        arc*-*-linux*.
+        * config/arc/t-multilib-linux: Specify MULTILIB_OPTIONS and
+        MULTILIB_DIRNAMES
+
+git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@260434 138bc75d-0d04-0410-961f-82ee72b054a4
+---
+ gcc/config.gcc                  |  2 +-
+ gcc/config/arc/t-multilib-linux | 25 +++++++++++++++++++++++++
+ 2 files changed, 26 insertions(+), 1 deletion(-)
+ create mode 100644 gcc/config/arc/t-multilib-linux
+
+diff --git a/gcc/config.gcc b/gcc/config.gcc
+index 96ae6a88a0db..d73e2cbc99a1 100644
+--- a/gcc/config.gcc
++++ b/gcc/config.gcc
+@@ -1061,7 +1061,7 @@ arc*-*-elf*)
+ 	;;
+ arc*-*-linux*)
+ 	tm_file="arc/arc-arch.h dbxelf.h elfos.h gnu-user.h linux.h linux-android.h glibc-stdint.h arc/linux.h ${tm_file}"
+-	tmake_file="${tmake_file} arc/t-arc"
++	tmake_file="${tmake_file} arc/t-multilib-linux arc/t-arc"
+ 	extra_gcc_objs="driver-arc.o"
+ 	if test "x$with_cpu" != x; then
+ 		tm_defines="${tm_defines} TARGET_CPU_BUILD=PROCESSOR_$with_cpu"
+diff --git a/gcc/config/arc/t-multilib-linux b/gcc/config/arc/t-multilib-linux
+new file mode 100644
+index 000000000000..f357cfc3f926
+--- /dev/null
++++ b/gcc/config/arc/t-multilib-linux
+@@ -0,0 +1,25 @@
++# Copyright (C) 2018 Free Software Foundation, 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/>.
++
++MULTILIB_OPTIONS = mcpu=hs/mcpu=archs/mcpu=hs38/mcpu=hs38_linux/mcpu=arc700/mcpu=nps400
++
++MULTILIB_DIRNAMES = hs archs hs38 hs38_linux arc700 nps400
++
++# Aliases:
++MULTILIB_MATCHES += mcpu?arc700=mA7
++MULTILIB_MATCHES += mcpu?arc700=mARC700
+-- 
+2.17.0
+