--target=powerpc64-linux_altivec: Use rs6000_linux64_override_options()?

[Segher Boessenkool]

Hi!

On Fri, Oct 28, 2022 at 07:34:24PM +0200, Jan-Benedict Glaw wrote:
> While checking my bot build logs, I noticed that GCC configured for
> --target=powerpc64-linux_altivec will pull in linux64.h and
> linuxaltivec.h .
> 
> linux64.h
>   * Will "#define TARGET_USES_LINUX64_OPT 1" (to make static void
>     rs6000_linux64_override_options() available in rs6000.cc).
>   * Will "#define SUBSUBTARGET_OVERRIDE_OPTIONS" to use
>     rs6000_linux64_override_options().
> 
> linuxaltivec.h OTOH
>   * Will undef / "#define SUBSUBTARGET_OVERRIDE_OPTIONS  rs6000_altivec_abi = 1"
>     and thus no longer use rs6000_linux64_override_options()
>   * That triggers a warning (unused-function).
> 
> To silence that warning, should linuxaltivec.h undefine
> TARGET_USES_LINUX64_OPT? Or set rs6000_altivec_abi=1 and call
> rs6000_linux64_override_options()?

Why do you use powerpc64-linux_altivec?  This things (normally spelled
with a dash, not and underscore, btw) was made for 32-bit targets.  It
never has done anything useful for 64-bit targets, afaik?

(And not for 32-bit targets either really, but that is another issue.)


Segher