[ovs-dev] [PATCH] lib/flow.h: Improve struct miniflow comment and definition.

[Ben Pfaff]

On Tue, Aug 26, 2014 at 04:04:09PM -0700, Jarno Rajahalme wrote:
> 
> On Aug 26, 2014, at 3:53 PM, Ben Pfaff <blp at nicira.com> wrote:
> 
> > On Tue, Aug 26, 2014 at 03:42:33PM -0700, Jarno Rajahalme wrote:
> >> Finally, use change the storage type of 'values_inline' to uint8_t, as
> >> uint64_t looks kind of wide for a boolean, even though we intend the
> >> bit be carved out from the uint64_t where 'map' resides.
> > 
> > It can't be type "bool"?
> 
> From CodingStyle:
> 
>   Declare bit-fields to be type "unsigned int" or "signed int".  Do
> *not* declare bit-fields of type "int": C89 allows these to be either
> signed or unsigned according to the compiler's whim.  (A 1-bit
> bit-field of type "int" may have a range of -1...0!)  Do not declare
> bit-fields of type _Bool or enum or any other type, because these are
> not portable.
> 
> :-)

This was important when we supported C89 compilers that did not have
native _Bool (bool), but I think that it is obsolete now, because all
of the compilers we support have C99 implementations good enough to
have native _Bool.

Let's find out and update CodingStyle if so.

Guru: does MSVC allow "bool" bit-fields?  I assume so but it's worth a
test.

Thanks,

Ben.