On Sat, Sep 28, 2019 at 12:40:52PM +0900, Junio C Hamano wrote:
> SZEDER Gábor <szeder.dev@xxxxxxxxx> writes:
>
> > On Fri, Sep 20, 2019 at 09:53:48AM -0700, William Baker via GitGitGadget wrote:
> >> diff --git a/midx.h b/midx.h
> >> index f0ae656b5d..e6fa356b5c 100644
> >> --- a/midx.h
> >> +++ b/midx.h
> >> @@ -37,6 +37,8 @@ struct multi_pack_index {
> >> char object_dir[FLEX_ARRAY];
> >> };
> >>
> >> +#define MIDX_PROGRESS (1 << 0)
> >
> > Please consider using an enum.
>
> If they are used by assiging one of their values, definitely a good
> idea to use an enum. Are debuggers clever enough that they can
> tell, when they see something like this:
>
> enum gress {
> PROGRESS = 1,
> REGRESS = 2,
> };
>
> void func(enum gress v);
>
> ...
>
> void caller(void)
> {
> func(PROGRESS | REGRESS);
> func(PROGRESS + REGRESS);
> func(PROGRESS * 3);
> }
>
> how caller came about to give 3?
No, they tend to show (PROGRESS | REGRESS), at least both gdb and lldb
do. If the enum has only constants with power-of-two values, then that
is the right way to write it, and the other two are asking for trouble
(e.g. after someone changes the value of REGRESS from 2 to 8,
'PROGRESS * 3' will mean something different).
