Re: [PATCH 4.9] ARM: 8723/2: always assume the "unified" syntax for assembly code

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

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On Mon, Apr 05, 2021 at 12:08:27PM -0700, Nathan Chancellor wrote:
> From: Nicolas Pitre <nicolas.pitre@linaro.org>
> 
> commit 75fea300d73ae5b18957949a53ec770daaeb6fc2 upstream.
> 
> The GNU assembler has implemented the "unified syntax" parsing since
> 2005. This "unified" syntax is required when the kernel is built in
> Thumb2 mode. However the "unified" syntax is a mixed bag of features,
> including not requiring a `#' prefix with immediate operands. This leads
> to situations where some code builds just fine in Thumb2 mode and fails
> to build in ARM mode if that prefix is missing. This behavior
> discrepancy makes build tests less valuable, forcing both ARM and Thumb2
> builds for proper coverage.
> 
> Let's "fix" this issue by always using the "unified" syntax for both ARM
> and Thumb2 mode. Given that the documented minimum binutils version that
> properly builds the kernel is version 2.20 released in 2010, we can
> assume that any toolchain capable of building the latest kernel is also
> "unified syntax" capable.
> 
> Whith this, a bunch of macros used to mask some differences between both
> syntaxes can be removed, with the side effect of making LTO easier.
> 
> Suggested-by: Robin Murphy <robin.murphy@arm.com>
> Signed-off-by: Nicolas Pitre <nico@linaro.org>
> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
> [nathan: Resolve small conflict on 4.9 due to a lack of 494609701e06a]
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>
> ---
> 
> Hi all,
> 
> This commit is needed to fix the backport of commit 7f9942c61fa6 ("ARM:
> s3c: fix fiq for clang IAS"):
> 
> https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org/message/MJWA3VGAUNQYOL7XZBYMS4EI4AYRC3XN/
> 
> It is present in 4.14+ and it has been validate via TuxSuite across a
> variety of arch/arm configs with no errors so I feel it should be a
> fairly safe backport.

Now queued up, thanks.

greg k-h