Hi, On Thu, Jan 09, 2025 at 02:29:19PM +0900, Akihiko Odaki wrote: > On 2025/01/08 22:50, Dave Martin wrote: > > On Wed, Jan 08, 2025 at 01:53:51PM +0900, Akihiko Odaki wrote: > > > On 2025/01/08 1:17, Dave Martin wrote: > > > > Hi, > > > > > > > > On Tue, Jan 07, 2025 at 09:45:56PM +0900, Akihiko Odaki wrote: > > > > > Use note name macros to match with the userspace's expectation. > > > > > > > > > > Signed-off-by: Akihiko Odaki <akihiko.odaki@xxxxxxxxxx> > > > > > --- > > > > > arch/s390/kernel/crash_dump.c | 62 ++++++++++++++++--------------------------- > > > > > 1 file changed, 23 insertions(+), 39 deletions(-) > > > > > > > > > > diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c > > > > > > > > [...] > > > > > > > +#define NT_INIT(buf, type, desc) \ > > > > > + (nt_init_name((buf), NT_ ## type, &(desc), sizeof(desc), NN_ ## type)) > > > > [...] > > > > > > (Note also, the outer parentheses and the parentheses around (buf) > > > > appear redundant -- although harmless?) > > > > > > They only make a difference in trivial corner cases and may look needlessly > > > verbose. > > > > (In case there was a misunderstanding here, I meant that some > > parentheses can be removed without affecting correctness: > > > > #define NT_INIT(buf, type, desc) \ > > nt_init_name(buf, NT_ ## type, &(desc), sizeof(desc), NN_ ## type)) > > > > It still doesn't matter though -- and some people do prefer to be > > defensive anyway and err on the side of having too many parentheses > > rather than too few.) > > Well, being very pedantic, there are some cases where these parentheses have > some effect. > > If you omit the outer parentheses, the following code will have different > consequences: > a->NT_INIT(buf, PRSTATUS, desc) > > The parentheses around buf will make difference for the following code: > #define COMMA , > NT_INIT(NULL COMMA buf, PRSTATUS, desc) > > But nobody will write such code. Ah, it looks like you're right on both! Apologies for the noise. (I must try find a neat use for these...) Cheers ---Dave
