[PATCH] Add gcc ARM flags -munaligned-access / -mno-unaligned-access

[Jeroen Hofstee]

Hello Renato,

On 08/17/2013 07:27 PM, Renato Golin wrote:
> AFAIK, if you don't specify strict-align, the back-end assumes 
> unaligned access is ok, so the behaviour is already covered.
>

See [1]. The default depends on the tripplet and the arm version.
For any unrecognised combination, llvm will default to only aligned
accesses.

> If you want GCC compatibility, you could just add the alias to strict 
> align, and a dummy option to no-strict-align?
>

If I make -munaligned-access a dummy (at least that what
I guess you mean), there is no proper way to allow unaligned
accesses on say one of the BSDs or e.g. armv6 and linux.
Both flags are needed to control alignment behaviour in general.

Regards,
Jeroen

[1] http://llvm.org/viewvc/llvm-project?view=revision&revision=182175