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Subject: Re: [PATCH 9/12] arm: Make libgcc bti compatible
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To: Andrea Corallo <andrea.corallo@arm.com>,
 Andrea Corallo via Gcc-patches <gcc-patches@gcc.gnu.org>
Cc: Richard Earnshaw <Richard.Earnshaw@arm.com>, nd <nd@arm.com>
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On 28/04/2022 10:48, Andrea Corallo via Gcc-patches wrote:
> This change add bti instructions at the beginning of arm specific
> libgcc hand written assembly routines.
> 
> 2022-03-31  Andrea Corallo  <andrea.corallo@arm.com>
> 
> 	* libgcc/config/arm/crti.S (FUNC_START): Add bti instruction if
> 	necessary.
> 	* libgcc/config/arm/lib1funcs.S (THUMB_FUNC_START, FUNC_START):
> 	Likewise.
> 

+#if defined(__ARM_FEATURE_BTI)

Wouldn't it be better to use __ARM_FEATURE_BTI_DEFAULT?  That way we 
only get BTI instructions in multilib variants that have asked for BTI.

R.