xgcc: Update gcc 5 to 5.4.0

patches synced with buildroot trunk and:
110-xtensa-implement-trap-pattern.patch (copied to 5.4.0 patches)
130-build_gcc-5_with_gcc-6.patch (upstreamed in 5.4.0, dropped)
370-gcc-plugin-Win-Dont-need-undefined-extern-var-refs-nor-fpic.patch (copied to 5.4.0 patches)
380-gcc-plugin-POSIX-include-sys-select-h.patch (copied to 5.4.0 patches)
910-nios2-bad-multilib-default.patch (copied to 5.4.0 patches)

config/cc/gcc.in

@@ -72,9 +72,9 @@ choice
 # Don't remove next line
 # CT_INSERT_VERSION_BELOW
 
-config CC_GCC_V_5_3_0
+config CC_GCC_V_5_4_0
     bool
-    prompt "5.3.0"
+    prompt "5.4.0"
     select CC_GCC_5
 
 config CC_GCC_V_linaro_5_2
@@ -261,7 +261,7 @@ config CC_GCC_VERSION
     string
 # Don't remove next line
 # CT_INSERT_VERSION_STRING_BELOW
-    default "5.3.0" if CC_GCC_V_5_3_0
+    default "5.4.0" if CC_GCC_V_5_4_0
     default "linaro-5.2-2015.11-2" if CC_GCC_V_linaro_5_2
     default "linaro-4.9-2015.06" if CC_GCC_V_linaro_4_9
     default "4.9.3" if CC_GCC_V_4_9_3

patches/gcc/5.4.0/874-xtensa-add-uclinux-support.patch

@@ -0,0 +1,174 @@
+From 70c2cb98fb129b4766b5da0f945dc41fd568c77a Mon Sep 17 00:00:00 2001
+From: Max Filippov <jcmvbkbc@gmail.com>
+Date: Sat, 22 Aug 2015 08:44:26 +0300
+Subject: [PATCH] xtensa: add uclinux support
+
+2015-10-03  Max Filippov  <jcmvbkbc@gmail.com>
+gcc/
+	* config.gcc (xtensa*-*-uclinux*): New configuration.
+	* config/xtensa/uclinux.h: New file.
+	* config/xtensa/uclinux.opt: New file.
+
+libgcc/
+	* config.host (xtensa*-*-uclinux*): New configuration.
+
+Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
+---
+Backported from: r228450
+
+ gcc/config.gcc                |  5 ++++
+ gcc/config/xtensa/uclinux.h   | 69 +++++++++++++++++++++++++++++++++++++++++++
+ gcc/config/xtensa/uclinux.opt | 32 ++++++++++++++++++++
+ libgcc/config.host            |  5 ++++
+ 4 files changed, 111 insertions(+)
+ create mode 100644 gcc/config/xtensa/uclinux.h
+ create mode 100644 gcc/config/xtensa/uclinux.opt
+
+diff --git a/gcc/config.gcc b/gcc/config.gcc
+index c52f5a8..56797bd 100644
+--- a/gcc/config.gcc
++++ b/gcc/config.gcc
+@@ -2995,6 +2995,11 @@ xtensa*-*-linux*)
+ 	tm_file="${tm_file} dbxelf.h elfos.h gnu-user.h linux.h glibc-stdint.h xtensa/linux.h"
+ 	tmake_file="${tmake_file} xtensa/t-xtensa"
+ 	;;
++xtensa*-*-uclinux*)
++	tm_file="${tm_file} dbxelf.h elfos.h gnu-user.h linux.h glibc-stdint.h xtensa/uclinux.h"
++	tmake_file="${tmake_file} xtensa/t-xtensa"
++	extra_options="${extra_options} xtensa/uclinux.opt"
++	;;
+ am33_2.0-*-linux*)
+ 	tm_file="mn10300/mn10300.h dbxelf.h elfos.h gnu-user.h linux.h glibc-stdint.h mn10300/linux.h"
+ 	gas=yes gnu_ld=yes
+diff --git a/gcc/config/xtensa/uclinux.h b/gcc/config/xtensa/uclinux.h
+new file mode 100644
+index 0000000..4606020
+--- /dev/null
++++ b/gcc/config/xtensa/uclinux.h
+@@ -0,0 +1,69 @@
++/* Xtensa uClinux configuration.
++   Derived from the configuration for GCC for Intel i386 running Linux.
++   Copyright (C) 2001-2015 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/>.  */
++
++#undef TARGET_OS_CPP_BUILTINS
++#define TARGET_OS_CPP_BUILTINS()				\
++  do								\
++    {								\
++      GNU_USER_TARGET_OS_CPP_BUILTINS ();			\
++      builtin_define ("__uClinux__");				\
++    }								\
++  while (0)
++
++#undef SUBTARGET_CPP_SPEC
++#define SUBTARGET_CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_REENTRANT}"
++
++#undef SIZE_TYPE
++#define SIZE_TYPE "unsigned int"
++
++#undef PTRDIFF_TYPE
++#define PTRDIFF_TYPE "int"
++
++#undef WCHAR_TYPE
++#define WCHAR_TYPE "long int"
++
++#undef WCHAR_TYPE_SIZE
++#define WCHAR_TYPE_SIZE 32
++
++#undef ASM_SPEC
++#define ASM_SPEC \
++ "%{mtext-section-literals:--text-section-literals} \
++  %{mno-text-section-literals:--no-text-section-literals} \
++  %{mtarget-align:--target-align} \
++  %{mno-target-align:--no-target-align} \
++  %{mlongcalls:--longcalls} \
++  %{mno-longcalls:--no-longcalls} \
++  %{mauto-litpools:--auto-litpools} \
++  %{mno-auto-litpools:--no-auto-litpools}"
++
++#undef LINK_SPEC
++#define LINK_SPEC "%{!no-elf2flt:%{!elf2flt*:-elf2flt}}"
++
++#undef LOCAL_LABEL_PREFIX
++#define LOCAL_LABEL_PREFIX	"."
++
++/* Always enable "-fpic" for Xtensa Linux.  */
++#define XTENSA_ALWAYS_PIC 1
++
++#undef TARGET_LIBC_HAS_FUNCTION
++#define TARGET_LIBC_HAS_FUNCTION no_c99_libc_has_function
++
++#undef DBX_REGISTER_NUMBER
++
+diff --git a/gcc/config/xtensa/uclinux.opt b/gcc/config/xtensa/uclinux.opt
+new file mode 100644
+index 0000000..95ef777
+--- /dev/null
++++ b/gcc/config/xtensa/uclinux.opt
+@@ -0,0 +1,32 @@
++; Xtensa uClinux options.
++
++; Copyright (C) 2015 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/>.
++
++; See the GCC internals manual (options.texi) for a description of
++; this file's format.
++
++; Please try to keep this file in ASCII collating order.
++
++elf2flt
++Driver
++
++elf2flt=
++Driver JoinedOrMissing
++
++; This comment is to ensure we retain the blank line above.
+diff --git a/libgcc/config.host b/libgcc/config.host
+index 2c64756..2ee92c1 100644
+--- a/libgcc/config.host
++++ b/libgcc/config.host
+@@ -1295,6 +1295,11 @@ xtensa*-*-linux*)
+ 	tmake_file="$tmake_file xtensa/t-xtensa xtensa/t-linux t-slibgcc-libgcc"
+ 	md_unwind_header=xtensa/linux-unwind.h
+ 	;;
++xtensa*-*-uclinux*)
++	tmake_file="$tmake_file xtensa/t-xtensa xtensa/t-linux t-slibgcc-libgcc"
++	md_unwind_header=xtensa/linux-unwind.h
++	extra_parts="$extra_parts crtbeginS.o crtbeginT.o crtendS.o"
++	;;
+ am33_2.0-*-linux*)
+ 	# Don't need crtbeginT.o from *-*-linux* default.
+ 	extra_parts="crtbegin.o crtend.o crtbeginS.o crtendS.o"
+-- 
+1.8.1.4
+

patches/gcc/5.4.0/890-fix-m68k-compile.patch

@@ -0,0 +1,15 @@
+remove unused header, which breaks the toolchain building
+
+Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
+
+diff -Nur gcc-5.3.0.orig/libgcc/config/m68k/linux-atomic.c gcc-5.3.0/libgcc/config/m68k/linux-atomic.c
+--- gcc-5.3.0.orig/libgcc/config/m68k/linux-atomic.c	2015-01-05 13:33:28.000000000 +0100
++++ gcc-5.3.0/libgcc/config/m68k/linux-atomic.c	2016-03-19 09:25:07.000000000 +0100
+@@ -33,7 +33,6 @@
+    using the kernel helper defined below.  There is no support for
+    64-bit operations yet.  */
+
+-#include <asm/unistd.h>
+ #include <stdbool.h>
+
+ #ifndef __NR_atomic_cmpxchg_32

patches/gcc/5.4.0/891-fix-m68k-uclinux.patch

@@ -0,0 +1,18 @@
+avoids internal compiler error while compiling linux-atomic.c
+See here:
+https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53833
+
+Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
+
+diff -Nur gcc-5.3.0.orig/libgcc/config.host gcc-5.3.0/libgcc/config.host
+--- gcc-5.3.0.orig/libgcc/config.host	2015-10-01 14:01:18.000000000 +0200
++++ gcc-5.3.0/libgcc/config.host	2016-04-26 21:30:25.353691745 +0200
+@@ -794,7 +794,7 @@
+ m68k*-*-openbsd*)
+ 	;;
+ m68k-*-uclinux*)	# Motorola m68k/ColdFire running uClinux with uClibc
+-	tmake_file="$tmake_file m68k/t-floatlib m68k/t-linux"
++	tmake_file="$tmake_file m68k/t-floatlib"
+ 	md_unwind_header=m68k/linux-unwind.h
+ 	;;
+ m68k-*-linux*)			# Motorola m68k's running GNU/Linux