RE: [PATCH 2/2] mempool: use rte constant macro instead of GCC builtin

["Morten Brørup" <mb@smartsharesystems.com>]

> From: Thomas Monjalon [mailto:thomas@monjalon.net]
> Sent: Wednesday, 3 July 2024 15.17
> 
> 14/06/2024 16:32, David Marchand:
> > On Wed, May 29, 2024 at 4:51 PM Thomas Monjalon <thomas@monjalon.net> wrote:
> > >
> > > 20/03/2024 22:33, Tyler Retzlaff:
> > > > Use newly introduced __rte_constant(e) macro instead of directly using
> > > > __builtin_constant_p() allowing mempool to be built by MSVC.
> > >
> > > Does it mean we should enable mempool build?
> > > If yes, please send a v2.
> >
> > I guess now it is possible, as I merged some other patches on mempool
> > from Stephen that were for MSVC.
> > Tyler, can you send a v2 so it passes through the CI?
> 
> I tried a retest last week and there is this failure on Ubuntu 24.04
> that I don't manage to reproduce locally:
> 
> /usr/include/x86_64-linux-gnu/bits/string_fortified.h:29:10: error: argument 2
> null where non-null expected [-Werror=nonnull]
> 29 |   return __builtin___memcpy_chk (__dest, __src, __len,
> |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 30 |                                  __glibc_objsize0 (__dest));
> |                                  ~~~~~~~~~~~~~~~~~~~~~~~~~~
> /usr/include/x86_64-linux-gnu/bits/string_fortified.h:29:10: note: in a call
> to built-in function '__builtin___memcpy_chk'
> In function 'memcpy',
> inlined from 'pcapng_add_option' at ../lib/pcapng/rte_pcapng.c:131:2,

pcapng_add_option() in rte_pcapng.c has memcpy() on line 132 [1] (and has a fix for this error, by comparing len > 0 before calling memcpy()); older versions had memcpy() on line 131, so the CI must be building with an older version of rte_pcapng.c.

[1]: https://elixir.bootlin.com/dpdk/v24.07-rc1/source/lib/pcapng/rte_pcapng.c#L132
[2]: https://elixir.bootlin.com/dpdk/v24.03/source/lib/pcapng/rte_pcapng.c#L131

> inlined from 'rte_pcapng_write_stats' at ../lib/pcapng/rte_pcapng.c:371:9:
> /usr/include/x86_64-linux-gnu/bits/string_fortified.h:29:10: error: argument 2
> null where non-null expected [-Werror=nonnull]
> 29 |   return __builtin___memcpy_chk (__dest, __src, __len,
> |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 30 |                                  __glibc_objsize0 (__dest));
> |                                  ~~~~~~~~~~~~~~~~~~~~~~~~~~
> /usr/include/x86_64-linux-gnu/bits/string_fortified.h:29:10: note: in a call
> to built-in function '__builtin___memcpy_chk'
> 
>