Re: IMMUTABLE and PARALLEL SAFE function markings

On Mon, Nov 26, 2018 at 11:20 PM Andrew Gierth
<andrew@tao11.riddles.org.uk> wrote:
> But the combination of inlining and polymorphism, in particular, makes
> it impossible for the function author to know this. Take the OP's
> example; it is parallel safe if and only if the selected type's equal
> function is parallel safe - how is the author supposed to know? What if
> the type is one installed later?

I think you have to set it conservatively.  It's easy to construct all
kinds of cases where a function is sometimes parallel-safe and
sometimes not depending on the parameters passed to it, but we don't
have any way to indicate that right now -- and I'm not entirely
convinced that we need one.

-- 
Robert Haas
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