Re: GinPageIs* don't actually return a boolean

On Tue, Aug 11, 2015 at 11:42 AM, Andres Freund <andres@anarazel.de> wrote:
> #define GinPageIsLeaf(page)    ( GinPageGetOpaque(page)->flags & GIN_LEAF )
> #define GinPageIsData(page)    ( GinPageGetOpaque(page)->flags & GIN_DATA )
> #define GinPageIsList(page)    ( GinPageGetOpaque(page)->flags & GIN_LIST )
> ...
>
> These macros don't actually return a boolean that's comparable with our
> true/false. That doesn't strike me as a good idea.
>
> If there's actually a boolean type defined by some included header (in
> which case we don't overwrite it in c.h!) this actually can lead to
> tests failing. If e.g. stdbool.h is included in c.h the tests fail with
> gcc-4.9.

!! is unknown to our codebase except where you've added it, and
personally, I hate that idiom.  I think we should write (val) != 0
instead of !!val.

-- 
Robert Haas
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