Exports from postgres

While working on the VC++ build, I initially (accidentally) built
postgres.exe witohut exporting all symbols (because VC++ doesn't have a
builtin functionality to do export-all). When enabling it to export all,
I noticed the binary increased more than 30% in size, and the linker
time increased around 500%. (The reason the function is not in vc++ is
that you're really not supposed to do full-exports from EXEs and
DLLs...)

Which brings me to the question - would it be reasonable to create a
.DEF file listing which symbols are exported from the postgres binary to
addon modules? Sort of the same way libpq does it, though of course with
a much more extensive list of functions. I have a feeling this might be
both more work than wanted, and something contrary to some piece of
design, but I'm throwing the question out to get some expert comments on
it.

//Magnus