[dpdk-dev] [PATCH] eal: remove register from function parameter in headers

[dpdk-dev] [PATCH] eal: remove register from function parameter in headers

[Stephen Hemminger]

Compiling a C++ application that includes directly or indirectly
rte_common.h will cause a warning:

include/rte_common.h:350:37: warning: ISO C++17 does not allow ‘register’ storage class specifier [-Wregister]
 rte_combine32ms1b(register uint32_t x)

C++ pickier than standard C and flags this antique usage.

This is a bugfix please apply to 20.05.
The register keyword is an old K&R legacy and should be removed
everywhere in DPDK. For now, fix it where it hurts.
Checkpatch should also be able to flag use of register keyword.

Fixes: 08f683174e94 ("eal: add functions for previous power of 2 alignment")
Cc: pbhagavatula@caviumnetworks.com
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---

 lib/librte_eal/include/rte_common.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/librte_eal/include/rte_common.h b/lib/librte_eal/include/rte_common.h
index 668e8b0af87d..0843ce69e7ec 100644
--- a/lib/librte_eal/include/rte_common.h
+++ b/lib/librte_eal/include/rte_common.h
@@ -409,7 +409,7 @@ __extension__ typedef uint64_t RTE_MARKER64[0];
  *    The combined value.
  */
 static inline uint32_t
-rte_combine32ms1b(register uint32_t x)
+rte_combine32ms1b(uint32_t x)
 {
 	x |= x >> 1;
 	x |= x >> 2;
@@ -431,7 +431,7 @@ rte_combine32ms1b(register uint32_t x)
  *    The combined value.
  */
 static inline uint64_t
-rte_combine64ms1b(register uint64_t v)
+rte_combine64ms1b(uint64_t v)
 {
 	v |= v >> 1;
 	v |= v >> 2;
-- 
2.20.1

Re: [dpdk-dev] [PATCH] eal: remove register from function parameter in headers

[Burakov, Anatoly]

On 09-May-20 12:25 AM, Stephen Hemminger wrote:
> Compiling a C++ application that includes directly or indirectly
> rte_common.h will cause a warning:
> 
> include/rte_common.h:350:37: warning: ISO C++17 does not allow ‘register’ storage class specifier [-Wregister]
>   rte_combine32ms1b(register uint32_t x)
> 
> C++ pickier than standard C and flags this antique usage.
> 
> This is a bugfix please apply to 20.05.
> The register keyword is an old K&R legacy and should be removed
> everywhere in DPDK. For now, fix it where it hurts.
> Checkpatch should also be able to flag use of register keyword.
> 
> Fixes: 08f683174e94 ("eal: add functions for previous power of 2 alignment")
> Cc: pbhagavatula@caviumnetworks.com
> Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> ---

I remember similar patches already being submitted, and the community 
has decided that 'register' keyword was worth keeping (although i don't 
recall the reasoning). Has something changed since then?

-- 
Thanks,
Anatoly

Re: [dpdk-dev] [PATCH] eal: remove register from function parameter in headers

[Bruce Richardson]

On Mon, May 11, 2020 at 09:56:10AM +0100, Burakov, Anatoly wrote:
> On 09-May-20 12:25 AM, Stephen Hemminger wrote:
> > Compiling a C++ application that includes directly or indirectly
> > rte_common.h will cause a warning:
> > 
> > include/rte_common.h:350:37: warning: ISO C++17 does not allow ‘register’ storage class specifier [-Wregister]
> >   rte_combine32ms1b(register uint32_t x)
> > 
> > C++ pickier than standard C and flags this antique usage.
> > 
> > This is a bugfix please apply to 20.05.
> > The register keyword is an old K&R legacy and should be removed
> > everywhere in DPDK. For now, fix it where it hurts.
> > Checkpatch should also be able to flag use of register keyword.
> > 
> > Fixes: 08f683174e94 ("eal: add functions for previous power of 2 alignment")
> > Cc: pbhagavatula@caviumnetworks.com
> > Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> > ---
> 
> I remember similar patches already being submitted, and the community has
> decided that 'register' keyword was worth keeping (although i don't recall
> the reasoning). Has something changed since then?
> 
I'm not sure anything has changed - and I don't see the need for register
keyword myself - but all headers must be includable in C++ code. Therefore
we need to remove register from rte_common.h

Acked-by: Bruce Richardson <bruce.richardson@intel.com>

Re: [dpdk-dev] [PATCH] eal: remove register from function parameter in headers

[David Marchand]

On Mon, May 11, 2020 at 11:05 AM Bruce Richardson
<bruce.richardson@intel.com> wrote:
>
> On Mon, May 11, 2020 at 09:56:10AM +0100, Burakov, Anatoly wrote:
> > On 09-May-20 12:25 AM, Stephen Hemminger wrote:
> > > Compiling a C++ application that includes directly or indirectly
> > > rte_common.h will cause a warning:
> > >
> > > include/rte_common.h:350:37: warning: ISO C++17 does not allow ‘register’ storage class specifier [-Wregister]
> > >   rte_combine32ms1b(register uint32_t x)
> > >
> > > C++ pickier than standard C and flags this antique usage.
> > >
> > > This is a bugfix please apply to 20.05.
> > > The register keyword is an old K&R legacy and should be removed
> > > everywhere in DPDK. For now, fix it where it hurts.
> > > Checkpatch should also be able to flag use of register keyword.
> > >
> > > Fixes: 08f683174e94 ("eal: add functions for previous power of 2 alignment")
Cc: stable@dpdk.org

> > > Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> Acked-by: Bruce Richardson <bruce.richardson@intel.com>

Applied, thanks.


-- 
David Marchand