On Wed, Oct 02, 2019 at 10:19:42AM -0700, Linus Torvalds wrote: > On Tue, Oct 1, 2019 at 11:16 PM Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote: > > > > I don't mind the use of ?: for choosing values, but it seems odd to me > > to use it for calling functions, as in: [from drivers/clocksource/timer-of.c), > > line 28 in Linux 5.4-rc1): > > > > of_irq->percpu ? free_percpu_irq(of_irq->irq, clkevt) : > > free_irq(of_irq->irq, clkevt); > > Ugh. It looks like a gcc extension for when the result of a > conditional expression isn't used. > > The result of the conditional expression _should_ be the type of > either side (usual type conversions). And it's fine if *both* sides > are of type 'void', then the result should be of that type too. > > But it looks like gcc (and clang) allow one side to be void, and the > result is void. > > Hmm. > > > gcc doesn't complain about the ?: usage. Is sparse correct here or is it being > > too strict? > > Sparse is correct, but maybe sparse should accept the gcc extension > except when in some strict mode? Yes, it shouldn't be a problem, certainly the 'one side is void and the result is void'. It makes sense. But I prefer to avoid something with 'unless the result isn't used', hehe. -- Luc
