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@gmx.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/PostgreSQL Development, 24x7 Support, Training &
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