Re: [PATCH] eal/ppc: undefine AltiVec keyword vector

[Ray Kinsella <mdr@ashroe.eu>]

Thomas Monjalon <thomas@monjalon.net> writes:

> 25/05/2022 20:34, Tyler Retzlaff:
>> On Wed, May 25, 2022 at 07:02:52PM +0100, Ray Kinsella wrote:
>> > Thomas Monjalon <thomas@monjalon.net> writes:
>> > > 25/05/2022 13:48, Ray Kinsella:
>> > >> Thomas Monjalon <thomas@monjalon.net> writes:
>> > >> 
>> > >> > The AltiVec header file is defining "vector", except in C++ build.
>> > >> > The keyword "vector" may conflict easily.
>> > >> > As a rule, it is better to use the alternative keyword "__vector".
>> > >> >
>> > >> > The DPDK header file rte_altivec.h takes care of undefining "vector",
>> > >> > so the applications and dependencies are free to define the name "vector".
>> > >> >
>> > >> > This is a compatibility breakage for applications which were using
>> > >> > the keyword "vector" for its AltiVec meaning.
>> > >> >
>> > >> > Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
>> > >> > ---
>> > >> >  doc/guides/rel_notes/release_22_07.rst | 5 +++++
>> > >> >  lib/eal/ppc/include/rte_altivec.h      | 7 +++++++
>> > >> >  2 files changed, 12 insertions(+)
>> > >> >
>> > >> 
>> > >> Acked-by: Ray Kinsella <mdr@ashroe.eu>
>> > >
>> > > Just to make sure, we are all OK to break compatibility of rte_altivec.h?
>> > > It means the keyword vector is not available anymore with this #include.
>> > > Please confirm it is OK to merge in DPDK 22.07.
>> > 
>> > I did think about it yes ;-).
>> > I can't see how it would break the ABI in the short term.
>> > And it makes sense to preclude this keyword in the long term.
>> > 
>> > So I ack'ed - did I miss something?
>> 
>> Acked-by: Tyler Retzlaff <roretzla@linux.microsoft.com>
>> 
>> double ack, impact of break is understood as follows.
>> 
>> * this is not an issue with abi it is an issue with api.
>> * the break will cause a compile failure, the action to resolve is to
>>   replace vector with __vector.
>
> Exactly
>
> I'll wait few days or acks from the techboard, and will apply.

+1

-- 
Regards, Ray K