[ANNOUNCE] Linaro GCC 6 and 7 2017.08 source snapshots

[Yvan Roux]

The Linaro Toolchain Working Group (TCWG) is pleased to announce the 2017.08
snapshot of Linaro GCC 6 and 7 source packages.

o The GCC 7 series introduced an ABI change for ARM targets by fixing a bug
(present since GCC 5, see link below) that affects conformance to the procedure
call standard (AAPCS). The bug affects some C++ code where class objects are
passed by value to functions and could result in incorrect or inconsistent code
being generated. If the option -Wpsabi is enabled (on by default) the compiler
will emit a diagnostic note for code that might be affected by this ABI change.

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77728

For an explanation of the changes please see the following website:

https://gcc.gnu.org/gcc-7/changes.html


o Linaro GCC 7 monthly snapshot[1] is based on FSF GCC 7.2+svn251138 and
includes performance improvements and bug fixes backported from mainline GCC.
The contents of this snapshot will be part of the 2017.11 stable[2] quarterly
release.

This snapshot tarball is available on:
http://snapshots.linaro.org/components/toolchain/gcc-linaro/7.2-2017.08/

Interesting changes in this GCC source package snapshot include:

* Updates to GCC 7.2+svn251138
* Backports from mainline:
- [Bugfix] [AArch32] PR target/79665: Improve Cortex-A53 shift bypass
- [Bugfix] PR lto/69866 lto1: internal compiler error: in
add_symbol_to_partition_1, at lto/lto-partition.c:158
- [AArch32] Improve Cortex-A53 FP scheduler
- [AArch64] Add rcpc extension
- [AArch64] Do not increase data alignment at -Os and with -fconserve-stack.
- [AArch64] Emit SIMD moves as mov
- [AArch64] Enable software prefetching (-fprefetch-loop-arrays) for
ThunderX 88xxx
- [AArch64] Fix atomic_cmp_exchange_zero_reg_1.c with +lse
- [AArch64] Fix failing lrint inline tests on bare-metal
- [AArch64] Fix ILP32 memory access
- [AArch64] Improve/correct ThunderX 1 cost model for Arith_shift
- [AArch64] Improve dup pattern
- [AArch64] Inline calls to lrint when possible
- [AArch64] Literal vector construction through vcombine is poor
- [Misc] Fold (A / (1 << B)) to (A >> B)
- [Testsuite] [AArch32] Allow arm_arch_*_ok to test several macros
- [Testsuite] [AArch32] Make gcc.target/arm/its.c more robust
- [Testsuite] [AArch32] Require arm_arch_v8a_ok for sdiv_costs_1.c
- [Testsuite] [AArch32] sdiv_costs_1.c: Disable on softfloat
- [Testsuite] [AArch32] sdiv_costs_1.c: Require arm_v8_vfp_ok
- [Testsuite] [AArch32] sdiv_costs_1.c: Use dg-add-options
- [Cleanup] [AArch64] Rearrange the processors in aarch64-cores.def
- [Cleanup] Update comment about is_leaf
- [Doc] [AArch64] Document RcPc extension


o Linaro GCC 6 monthly snapshot[1] is based on FSF GCC 6.4+svn251111 and
includes performance improvements and bug fixes backported from mainline GCC.
This snapshot contents will be part of the next maintenance release.

This snapshot tarball is available on:
http://snapshots.linaro.org/components/toolchain/gcc-linaro/6.4-2017.08/

Interesting changes in this GCC source package snapshot include:

* Updates to GCC 6.4+svn251111


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stay on top of Linaro development.

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[1]. Source package snapshots are defined when the compiler is only
put through unit-testing and full validation is not performed.

[2]. Stable source package releases are defined as releases where the
full Linaro Toolchain validation plan is executed.