Re: Create function prototype as part of PG_FUNCTION_INFO_V1

On 2014-02-17 10:30:16 -0300, Alvaro Herrera wrote:
> Tom Lane wrote:
> > Peter Eisentraut <peter_e(at)gmx(dot)net> writes:
> > > On 2/15/14, 10:22 AM, Tom Lane wrote:
> > >> Yes it does; people who fail to remove their manual externs will get
> > >> Windows-only build failures (or at least warnings; it's not very clear
> > >> which declaration will win).
> >
> > > The manual externs and the automatically provided ones are exactly the
> > > same. Why would that fail?
> >
> > Maybe I'm remembering the wrong patch. I thought what this patch was
> > intending was to put PGDLLEXPORT into the automatically-provided externs.
>
> This hunk is the essence of this patch:
>
> #define PG_FUNCTION_INFO_V1(funcname) \
> +Datum funcname(PG_FUNCTION_ARGS); \
> extern PGDLLEXPORT const Pg_finfo_record * CppConcat(pg_finfo_,funcname)(void); \
>
>
> Note that PGDLLEXPORT is already there. This patch is just about
> additionally providing the prototype.

The PGDLLEXPORT is attached to the variable, no the function tho. If
somebody previously tried to do the correct thing and attached
PGDLLEXPORT to their own *function* prototoype, it would cause problems
now.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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