[Buildroot] [PATCH 3/5 v2] toolchain: check the SSP option is known

[Arnout Vandecappelle]

On 12/03/2019 13:09, yann.morin at orange.com wrote:
> From: "Yann E. MORIN" <yann.morin at orange.com>
> 
> Some toolchain vendors may have backported those options to older gcc
> versions, and we have no way to know, so we have to check that the
> user's selection is acceptable.
> 
> Extend the macro that currently checks for SSP in the toolchain, with
> a new test that the actual SSP option is recognised and accepted.
> 
> Note that the SSP option is either totaly empty, or an already-quoted
> string, so we can safely and easily assign it to a shell variable to
> test and use it.
> 
> Note that we do not introduce BR2_TOOLCHAIN_HAS_SSP_STRONG, because:
> 
>   - our internal toolchain infra only supports gcc >= 4.9, so it has
>     SSP strong;
> 
>   - of the external pre-built toolchains, only the codesourcery-arm
>     one has a gcc-4.8 which lacks SSP strong, all the others have a
>     gcc >= 4.9;
> 
>   - we'd still have to do the actual check for custom external
>     toolchains anyway.
> 
> So, we're not adding BR2_TOOLCHAIN_HAS_SSP_STRONG just for a single
> case.
> 
> Signed-off-by: "Yann E. MORIN" <yann.morin at orange.com>
> Cc: Matt Weber <matthew.weber at rockwellcollins.com>
> Cc: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
> Cc: Thomas De Schampheleire <thomas.de_schampheleire at nokia.com>
> Cc: Arnout Vandecappelle <arnout at mind.be>

 You replied to all concerns, so I've applied as-is.

 Regards,
 Arnout