toolchain: add support of ARC architecture

This includes binutils, gcc, gdb and uClibc-ng.

Latest release of ARC gcc (as of today it is "arc-2015.06")
is based on upstream gcc 4.8.4.

Sources are available on GitHub, see:
https://github.com/foss-for-synopsys-dwc-arc-processors/gcc

Latest release of ARC binutils (as of today it is "arc-2015.06")
is based on upstream binutils 2.23.

Sources are available on GitHub, see:
https://github.com/foss-for-synopsys-dwc-arc-processors/binutils-gdb/releases/tag/arc-2015.06

Latest release of ARC GDB (as of today this is "arc-2015.06-gdb")
is based on upstream gdb 7.9.1.

Sources are available on GitHub, see:
https://github.com/foss-for-synopsys-dwc-arc-processors/binutils-gdb/releases/tag/arc-2015.06-gdb

Note that for binutils and gdb that come from unified git repository
(which is the case for upstream binutils/gdb today) we need to disable
building of gdb in binutils and binutils in gdb hence in binutils:
------>8------
--disable-sim
--disable-gdb
------>8------

and in gdb:
------>8------
--disable-binutils
--disable-ld
--disable-gas
------>8------

Also in gdb we disable sim because if the following breakage while
building with it:
------------>8------------
/usr/bin/env bash ./../common/genmloop.sh -shell /usr/bin/env bash \
        -mono -fast -pbb -switch sem5-switch.c \
        -cpu a5f -infile ./mloop5.in \
        -outfile-suffix 5
unknown option: bash
Makefile:699: recipe for target 'stamp-5mloop' failed
make[7]: *** [stamp-5mloop] Error 1
------------>8------------

Cc: Felix Fietkau <nbd@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: Jonas Gorski <jogo@openwrt.org>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

SVN-Revision: 47438

1 files changed, 94 insertions, 0 deletions

diff --git a/toolchain/gcc/patches/arc-2015.06/003-universal_initializer.patch b/toolchain/gcc/patches/arc-2015.06/003-universal_initializer.patch
new file mode 100644
index 0000000..1b9a5b3
--- /dev/null
+++ b/toolchain/gcc/patches/arc-2015.06/003-universal_initializer.patch
@@ -0,0 +1,94 @@
+--- a/gcc/c/c-typeck.c
++++ b/gcc/c/c-typeck.c
+@@ -62,9 +62,9 @@ int in_typeof;
+    if expr.original_code == SIZEOF_EXPR.  */
+ tree c_last_sizeof_arg;
+ 
+-/* Nonzero if we've already printed a "missing braces around initializer"
+-   message within this initializer.  */
+-static int missing_braces_mentioned;
++/* Nonzero if we might need to print a "missing braces around
++   initializer" message within this initializer.  */
++static int found_missing_braces;
+ 
+ static int require_constant_value;
+ static int require_constant_elements;
+@@ -6363,6 +6363,9 @@ static int constructor_nonconst;
+ /* 1 if this constructor is erroneous so far.  */
+ static int constructor_erroneous;
+ 
++/* 1 if this constructor is the universal zero initializer { 0 }.  */
++static int constructor_zeroinit;
++
+ /* Structure for managing pending initializer elements, organized as an
+    AVL tree.  */
+ 
+@@ -6524,7 +6527,7 @@ start_init (tree decl, tree asmspec_tree
+   constructor_stack = 0;
+   constructor_range_stack = 0;
+ 
+-  missing_braces_mentioned = 0;
++  found_missing_braces = 0;
+ 
+   spelling_base = 0;
+   spelling_size = 0;
+@@ -6619,6 +6622,7 @@ really_start_incremental_init (tree type
+   constructor_type = type;
+   constructor_incremental = 1;
+   constructor_designated = 0;
++  constructor_zeroinit = 1;
+   designator_depth = 0;
+   designator_erroneous = 0;
+ 
+@@ -6816,11 +6820,8 @@ push_init_level (int implicit, struct ob
+ 	set_nonincremental_init (braced_init_obstack);
+     }
+ 
+-  if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
+-    {
+-      missing_braces_mentioned = 1;
+-      warning_init (OPT_Wmissing_braces, "missing braces around initializer");
+-    }
++  if (implicit == 1)
++    found_missing_braces = 1;
+ 
+   if (TREE_CODE (constructor_type) == RECORD_TYPE
+ 	   || TREE_CODE (constructor_type) == UNION_TYPE)
+@@ -6953,16 +6954,23 @@ pop_init_level (int implicit, struct obs
+ 	}
+     }
+ 
++  if (vec_safe_length (constructor_elements) != 1)
++    constructor_zeroinit = 0;
++
++  /* Warn when some structs are initialized with direct aggregation.  */
++  if (!implicit && found_missing_braces && warn_missing_braces
++      && !constructor_zeroinit)
++    {
++      warning_init (OPT_Wmissing_braces,
++		    "missing braces around initializer");
++    }
++
+   /* Warn when some struct elements are implicitly initialized to zero.  */
+   if (warn_missing_field_initializers
+       && constructor_type
+       && TREE_CODE (constructor_type) == RECORD_TYPE
+       && constructor_unfilled_fields)
+     {
+-	bool constructor_zeroinit =
+-	 (vec_safe_length (constructor_elements) == 1
+-	  && integer_zerop ((*constructor_elements)[0].value));
+-
+ 	/* Do not warn for flexible array members or zero-length arrays.  */
+ 	while (constructor_unfilled_fields
+ 	       && (!DECL_SIZE (constructor_unfilled_fields)
+@@ -8077,6 +8085,9 @@ process_init_element (struct c_expr valu
+   designator_depth = 0;
+   designator_erroneous = 0;
+ 
++  if (!implicit && value.value && !integer_zerop (value.value))
++    constructor_zeroinit = 0;
++
+   /* Handle superfluous braces around string cst as in
+      char x[] = {"foo"}; */
+   if (string_flag