The Linaro Toolchain Working Group (TCWG) is pleased to announce the 2017.07 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 7.1+svn250046 and includes performance improvements and bug fixes backported from mainline GCC. The contents of this snapshot will be part of the 2017.08 stable[2] quarterly release.

This snapshot tarball is available on: http://snapshots.linaro.org/components/toolchain/gcc-linaro/7.1-2017.07/

Interesting changes in this GCC source package snapshot include:

* Updates to GCC 7.1+svn250046 * Backport of [Bugfix] [AArch32] PR target/71778 ICE using non-constant argument to Neon intrinsic that requires constant arguments * Backport of [Bugfix] [AArch64] PR target/71663 aarch64 Vector initialization can be improved slightly * Backport of [AArch32] Enable FP16 vector arithmetic operations * Backport of [AArch32] Fix ARM bootstrap failure due to an odd warning * Backport of [AArch32] Modify idiv costs for Cortex-A53 * Backport of [AArch64] Add combine pattern for storing lane zero of a vector * Backport of [AArch64] Add HF vector modes to lane-to-lane INS pattern * Backport of [AArch64] Add prefetch configuration to aarch64 backend * Backport of [AArch64] Adjust costs so udiv is preferred over sdiv when both are valid * Backport of [AArch64] Allow CMP+SHIFT when comparing with zero * Backport of [AArch64] Allow const0_rtx operand for atomic compare-exchange patterns * Backport of [AArch64] Emit tighter strong atomic compare-exchange loop when comparing against zero * Backport of [AArch64] Enable -fprefetch-loop-arrays at given optimization level * Backport of [AArch64] Fix -fstack-check with really big frames on aarch64 * Backport of [AArch64] Fix subreg bug in scalar copysign * Backport of [AArch64] Peephole for SUBS * Backport of [AArch64] Simplify call, call_value, sibcall, sibcall_value patterns * Backport of [AArch64] Update prefetch tuning parameters for qdf24xx. * Backport of [AArch64] Use SUBS for parallel subtraction and comparison with immediate * Backport of [Misc] Add debug counter for loop array prefetching * Backport of [Misc] Improve debug output of loop data prefetching * Backport of [Cleanup] [AArch32] Complete legend for ARM register allocation in arm.h * Backport of [Cleanup] [AArch32] Fix comment for cmse_nonsecure_call_clear_caller_saved * Backport of [Cleanup] [AArch32] Fix typo in comment in arm_expand_prologue * Backport of [Testsuite] [AArch32] Add MOVT testing for ARMv8-M Baseline * Backport of [Testsuite] Add dg-require-stack-check * Backport of [Testsuite] Fix stack-check-1.c

o Linaro GCC 6 monthly snapshot[1] is based on FSF GCC 6.4+svn250045 and includes performance improvements and bug fixes backported from mainline GCC. This snapshot contents will be part of the 2017.08 stable[2] quarterly release.

This snapshot tarball is available on: http://snapshots.linaro.org/components/toolchain/gcc-linaro/6.4-2017.07/

Interesting changes in this GCC source package snapshot include:

* Updates to GCC 6.4+svn250045 * Linaro BZ #3040 -- CC1 and cc1plus cannot convert UTF-8: Regenerate intl configure * Backport of [AArch64] Fix -fstack-check with really big frames on aarch64 * Backport of [Testsuite] Add dg-require-stack-check * Backport of [Testsuite] Fix stack-check-1.c

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* Bug reports should be filed in bugzilla against GCC product: http://bugs.linaro.org/enter_bug.cgi?product=GCC * Interested in commercial support? inquire at "Linaro support": mailto:support@linaro.org

[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.