[glibc] Documentation for ARC port

[glibc] Documentation for ARC port

[Vineet Gupta]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=758caf37366c3bebd349cd3107341dbfd761189a

commit 758caf37366c3bebd349cd3107341dbfd761189a
Author: Vineet Gupta <vgupta@synopsys.com>
Date:   Mon Nov 20 12:46:17 2017 -0800

    Documentation for ARC port
    
    (a) ABI doc:
        https://github.com/foss-for-synopsys-dwc-arc-processors/toolchain/wiki/files/ARCv2_ABI.pdf
    
    (b) Programmer's Reference Manual (PRM) : needs a download request to be filled
        https://www.synopsys.com/dw/ipdir.php?ds=arc-hs44-hs46-hs48
        https://www.synopsys.com/dw/doc.php/ds/cc/programmers-reference-manual-ARC-HS.pdf
    
    As of port merge (and Florian's patch to fix static TLS), glibc testsuite
    (cross-test setup) has following failures:
    
    FAIL: elf/tst-audit14
    FAIL: elf/tst-audit15
    FAIL: elf/tst-audit16
    FAIL: elf/tst-ldconfig-ld_so_conf-update
    FAIL: elf/tst-libc_dlvsym
    FAIL: elf/tst-libc_dlvsym-static
    FAIL: iconv/test-iconvconfig            # Needs gconv installed
    FAIL: io/ftwtest                        # Requires execution by non-root
    FAIL: io/tst-lockf
    FAIL: libio/tst-wfile-sync
    FAIL: locale/tst-localedef-path-norm
    FAIL: nptl/test-cond-printers           # needs Python3 and target GDB on target
    FAIL: nptl/test-condattr-printers       #    ditto
    FAIL: nptl/test-mutex-printers          #    ditto
    FAIL: nptl/test-mutexattr-printers      #    ditto
    FAIL: nptl/test-rwlock-printers         #    ditto
    FAIL: nptl/test-rwlockattr-printers     #    ditto
    FAIL: nptl/tst-umask1                   # passes if run natively on target (NFS ACLv3 support needed)
    FAIL: nss/bug-erange
    FAIL: nss/tst-nss-files-hosts-getent
    FAIL: nss/tst-nss-files-hosts-multi
    FAIL: posix/bug-ga2
    FAIL: posix/globtest                    # require same user on target and host
    FAIL: posix/tst-getaddrinfo5
    FAIL: stdio-common/tst-vfprintf-width-prec
    FAIL: stdio-common/tst-vfprintf-width-prec-alloc
    FAIL: stdio-common/tst-vfprintf-width-prec-mem
    FAIL: string/tst-strerror
    FAIL: string/tst-strsignal
    FAIL: sunrpc/bug20790                   # missing cpp on target
    FAIL: timezone/tst-tzset
    
    Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

Diff:
---
 NEWS                | 11 +++++++++++
 README              |  1 +
 manual/install.texi |  4 ++++
 3 files changed, 16 insertions(+)

diff --git a/NEWS b/NEWS
index 0b25b4fde9..92dcb77fef 100644
--- a/NEWS
+++ b/NEWS
@@ -15,6 +15,17 @@ Major new features:
 
 * New locale added: ckb_IQ (Kurdish/Sorani spoken in Iraq)
 
+* Support for Synopsys ARC HS cores (ARCv2 ISA) running Linux has been
+  added. This port requires at least binutils-2.32, gcc-8.3 and Linux-5.1.
+  Three ABIs are supported:
+
+     - arc-linux-gnu
+     - arc-linux-gnuhf
+     - arceb-linux-gnu
+
+  The arc* ABI is little-endian while arceb is big-endian. All ABIs use
+  64-bit time (y2038 safe) and 64-bit file offsets (LFS default).
+
 * The GNU C Library now loads audit modules listed in the DT_AUDIT and
   DT_DEPAUDIT dynamic section entries of the main executable.
 
diff --git a/README b/README
index 31c5da0405..903f07e484 100644
--- a/README
+++ b/README
@@ -24,6 +24,7 @@ The GNU C Library supports these configurations for using Linux kernels:
 
 	aarch64*-*-linux-gnu
 	alpha*-*-linux-gnu
+	arc*-*-linux-gnu
 	arm-*-linux-gnueabi
 	csky-*-linux-gnuabiv2
 	hppa-*-linux-gnu
diff --git a/manual/install.texi b/manual/install.texi
index ea0059a4ec..735e99bb03 100644
--- a/manual/install.texi
+++ b/manual/install.texi
@@ -512,6 +512,8 @@ Library with support for IEEE long double.
 @c powerpc64le performs an autoconf test to verify the compiler compiles with
 @c commands like "$CC -c foo.c -mabi=ibmlongdouble -mlong-double-128".
 
+For ARC architecture builds, GCC 8.3 or higher is needed.
+
 For multi-arch support it is recommended to use a GCC which has been built with
 support for GNU indirect functions.  This ensures that correct debugging
 information is generated for functions selected by IFUNC resolvers.  This
@@ -537,6 +539,8 @@ For PowerPC 64-bits little-endian (powerpc64le), @command{objcopy} is required
 to support @option{--update-section}.  This option requires binutils 2.26 or
 newer.
 
+ARC architecture needs @code{binutils} 2.32 or higher for TLS related fixes.
+
 @item
 GNU @code{texinfo} 4.7 or later