[Buildroot] [PATCHv2] toolchain-wrapper: Disable -ftree-loop-distribute-patterns when building for microblaze with gcc >= 10

[Thomas Petazzoni]

On Tue,  6 Oct 2020 22:29:20 +0200
Romain Naour <romain.naour at gmail.com> wrote:

> GCC 10 now enable by default -ftree-loop-distribute-patterns at -O2 or -Os
> optimization level instead of -O3, see commit [1].
> 
> Due to this change, the microblaze kernel doesn't boot (as reported by
> toolchain-builder project).
> 
> The gcc docs between version 9 and 10 has been updated accordingly [2] [3]
> but there no word about this change in the gcc 10 changelog [4].
> 
> Fixes microblazebe:
> https://gitlab.com/bootlin/toolchains-builder/-/jobs/729359536 (glibc)
> https://gitlab.com/bootlin/toolchains-builder/-/jobs/729359538 (musl)
> https://gitlab.com/bootlin/toolchains-builder/-/jobs/729359540 (uClubc-ng)
> 
> Fixes microblazeel:
> https://gitlab.com/bootlin/toolchains-builder/-/jobs/729359542 (glibc)
> https://gitlab.com/bootlin/toolchains-builder/-/jobs/729359544 (musl)
> https://gitlab.com/bootlin/toolchains-builder/-/jobs/729359546 (uClibc-ng)
> 
> This has been reported upsteam [5].
> 
> [1] https://gcc.gnu.org/git/?p=gcc.git;a=commitdiff;h=5879ab5fafedc8f6f9bfe95a4cf8501b0df90edd
> [2] https://gcc.gnu.org/onlinedocs/gcc-9.3.0/gcc/Optimize-Options.html#Optimize-Options
> [3] https://gcc.gnu.org/onlinedocs/gcc-10.2.0/gcc/Optimize-Options.html#Optimize-Options
> [4] https://gcc.gnu.org/gcc-10/changes.html
> [5] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97208
> 
> Signed-off-by: Romain Naour <romain.naour at gmail.com>
> Cc: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
> ---
> It's not clear if building the kernel with gcc 9 and -O3 trigger this issue.
> It has been noticed by the change from [1].

Applied to master, thanks.

Thomas
-- 
Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com