This release includes the following items:
* Bare metal EABI pre-built binaries for running on a Windows host
* Bare metal EABI pre-built binaries for running on a Linux host
* Bare metal EABI pre-built binaries for running on a Mac OS X host
* Source code package (together with build scripts and instructions to setup
  build environment), composed of:
  * gcc : ARM/embedded-5-branch revision 240432
    http://gcc.gnu.org/svn/gcc/branches/ARM/embedded-5-branch/

  * binutils : 2.26 prerelease with mainline backports
    git://sourceware.org/git/binutils-gdb.git commit 9dd9f850edab6ea48293ef6b1000ce178e9016f0

  * newlib and newlib-nano : current master with mainline backports
    git://sourceware.org/git/newlib-cygwin.git commit f763e2dc88d04430dd2524a529eef91a2e517e4e

  * gdb : 7.10 without target sim support
    git://sourceware.org/git/binutils-gdb.git commit 23c16316b1309b20016a74c50025c9d62c237de8

  * cloog 0.18.0 :
    ftp://gcc.gnu.org/pub/gcc/infrastructure/cloog-0.18.0.tar.gz

  * expat 2.0.1 :
    http://jaist.dl.sourceforge.net/project/expat/expat/2.0.1/expat-2.0.1.tar.gz

  * gmp 4.3.2 : ftp://gcc.gnu.org/pub/gcc/infrastructure/gmp-4.3.2.tar.bz2

  * libelf 0.8.13 : http://www.mr511.de/software/libelf-0.8.13.tar.gz

  * libiconv 1.14 :
    http://ftp.gnu.org/gnu/libiconv/libiconv-1.14.tar.gz

  * mpc 0.8.1 : ftp://gcc.gnu.org/pub/gcc/infrastructure/mpc-0.8.1.tar.gz

  * mpfr 2.4.2 : ftp://gcc.gnu.org/pub/gcc/infrastructure/mpfr-2.4.2.tar.bz2

  * isl 0.12.2 : ftp://gcc.gnu.org/pub/gcc/infrastructure/isl-0.12.2.tar.bz2

  * zlib 1.2.8
    http://sourceforge.net/projects/libpng/files/zlib/1.2.8/zlib-1.2.8.tar.gz/download

Supported hosts:
* Windows 7 32/64 bits (with installer and alternative zip package)
* Linux 32/64 bits
  - Ubuntu 8.x or later (tarball)
  - Ubuntu 12.04/14.04/15.04/15.10/16.04 (tarball and PPA)
  - RHEL 4/5/6/7 (tarball)
* Mac OS X 10.7.3 and newer 64 bits (tarball)

Supported target OS:
* Bare metal EABI only.

Features:
* All GCC 5 features, plus latest mainline features:
  + Cortex-R8 support
  + Cortex-M7 performance tuning
  + optimization of manual little endian and big endian loads
  + improved jump threading removing the need for -ftree-switch-shortcut
* Armv8-M Baseline and Mainline beta support:
  + Armv8-M Security Extensions Alpha support
* Arm PureCode support
* Thumb-1 library optimizations
  + https://gcc.gnu.org/ml/gcc-patches/2015-10/msg01282.html
* CRC optimization
  + https://gcc.gnu.org/ml/gcc-patches/2015-11/msg02046.html
* Smaller terminate handler for newlib-nano
* Re-tied the MALLOC_LOCK and MALLOC_UNLOCK to newlib's multithread configuration for newlib-nano.
* Thumb-2 long branch veneers.

Tests:
* Tested on a variety of Cortex-M0/M0+/M3/M4/M7/A9 boards
* Tested on Qemu
* Tested on Arm Fast Models

Important bugs fixed in 5 update 1 release:
* https://answers.launchpad.net/gcc-arm-embedded/+question/267037
* https://bugs.launchpad.net/gcc-arm-embedded/+bug/1534360
* https://answers.launchpad.net/gcc-arm-embedded/+question/286502
* A bug that caused gdb's target remote command to behave unexpectedly when
  debugging simple programs

Important bugs fixed in 5 update 2 release:
* Fixed code-size regression for Cortex-M0 compared to 4.9 when compiling with -Os
* Fix multilib used for armv8-m.main+dsp
* Fix use of --gc-sections when building for Armv8-M with Security Extensions
* Fix memcpy used for newlib-nano for pre Armv6T2 devices
* Fix alignment of .data in ldscripts in samples
* Fix semihosting for Armv7-A and Armv7-R

Important bugs fixed in 5 update 3 release:
* Removed MSP_S and PSP_S MRS/MSR special registers
* Fixed Thumb version detection in veneer generation
* Fixed documentation about newlib-nano in release.txt

Known Changes and Issues:
* Thumb1 code size regression due to new register allocation:
  https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61578
  https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59535
A workaround is to disable it by option -mno-lra.
* The use of 64-bit atomic operations for Armv8-M is not supported.