Re: [PATCH, BFD, LD, AArch64, 0/4] Add support for AArch64 BTI and PAC in the linker

[Nick Clifton <nickc at redhat dot com>]

Hi Sudi,

>> OK, so just to be clear, with --bti or --bti-nowarn the output will be
>> given the BTI tag *even if* some of the input files do not have the BTI note ?

> Yes

> can go back and check the objects that need recompiling or use 
> --bti-nowarn when they are sure that even if there is any object with 
> missing BTI note section it is still safe to turn on BTI (or they still 
> want to turn on BTI). We think that these options would be most helpful 
> in early deployment.

OK, well I get the --bti option then, but I still think that --bti-nowarn
is a mistake.  Given that --bti will only generate warnings if there are
object files without the BTI note, and warnings can be ignored, I do not
see the need for --bti-nowarn.  Plus using --bti-nowarn could potentially
cause problems if the developer forgets (or does not know) that it is 
enabled, and they end up thinking that they are creating BTI enabled 
binaries when in fact they are not.

If a developer really wants to skip the warnings they could pipe the
output from the linker through a grep that eliminates them.  Which would
have the added benefit of being more visible in the output logs of a 
complex build than a single command line option.

Cheers
  Nick