Re: popen and pclose redefinitions causing many warning in Windows build

On Thu, May 08, 2014 at 12:14:44PM -0400, Tom Lane wrote:
> Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
> > I'm pretty sure we need this on Mingw - this SYSTEMQUOTE stuff dates
> > back well before 8.3, IIRC, which is when we first got full MSVC support.
>
> I tried googling for some info on this, and got a number of hits
> suggesting that mingw didn't emulate popen at all till pretty recently.
> For instance this:
> https://lists.fedoraproject.org/pipermail/fedora-mingw/2009-September/002087.html
> Jones is an ex-coworker of mine, and I'm pretty sure that if he said
> it wasn't there then it wasn't there.

I doubt MinGW has overridden popen() at runtime; that would be contrary to its
design criteria. The headers, however, are MinGW territory. MinGW declares
both _popen() and popen() as functions. MinGW-w64, a project more distinct
from MinGW than it sounds, uses "#define popen _popen":

MinGW: http://sourceforge.net/p/mingw/mingw-org-wsl/ci/master/tree/include/stdio.h#l467
MinGW-w64: http://sourceforge.net/p/mingw-w64/code/HEAD/tree/trunk/mingw-w64-headers/crt/stdio.h#l496

Building with any recent MinGW-w64, 32-bit or 64-bit, gets the reported
warnings; building with MinGW proper does not.

--
Noah Misch
EnterpriseDB http://www.enterprisedb.com