[dpdk-dev] [RFC] toolchain specific macro expansion

[Tyler Retzlaff]

On Wed, Jul 07, 2021 at 10:35:56PM +0200, Thomas Monjalon wrote:
> 07/07/2021 22:23, Tyler Retzlaff:
> > On Thu, Jun 24, 2021 at 06:29:20PM +0200, Thomas Monjalon wrote:
> > > 24/06/2021 18:02, Tyler Retzlaff:
> > > > On Thu, Jun 24, 2021 at 08:54:49AM +0200, Thomas Monjalon wrote:
> > > > > 23/06/2021 20:26, Tyler Retzlaff:
> > > > > > // lib/eal/gcc/rte_toolchain_common.h
> > > > > > #define __rte_noreturn __attribute__((noreturn))
> > > > > 
> > > > > We should keep a macro in rte_common.h which triggers an explicit error
> > > > 
> > > > i think that's relatively trivial to do. rte_common.h could after
> > > > toolchain specific include do a simple test.
> > > > 
> > > > #ifndef __rte_no_return
> > > > #error no __rte_no_return defined for toolchain
> > > > #endif
> > > 
> > > No I was thinking of:
> > > 
> > > /** Doxygen comment for the attribute below */
> > > #define __rte_no_return RTE_ATTR_NOT_SUPPORTED
> > 
> > when you suggested this i thought it was something already established.
> > i see now that's not the case.  would you mind elaborating a little with
> > a complete example of the toolchain specific override and the generic
> > include?  i'd just like to understand completely what you were
> > proposing so i can try it out.
> 
> Sorry I don't have time currently to elaborate,
> and not sure how to implement it.
> I may look at it next week if that's the way we want to go.

i think the community generally preferences not having obvious
conditional compilation on a per-macro basis so i think it is the way we
want to go.

i'll take a look at the existing uses of include/generic/foo.h and
<arch>/include/foo.h where the arch specific includes generic for
inspiration. but i look forward to seeing what you come up with when you
get a chance to focus on the topic.