Provide DLLEXPORT markers for C functions via PG_FUNCTION_INFO_V1 macro.
Second try at the change originally made in commit
8518583cd;
this time with contrib updates so that manual extern declarations
are also marked with PGDLLEXPORT. The release notes should point
this out as a significant source-code change for extension authors,
since they'll have to make similar additions to avoid trouble on Windows.
Laurenz Albe, doc change by me
Patch: <
A737B7A37273E048B164557ADEF4A58B53962ED8@ntex2010a.host.magwien.gv.at>