Make a separate win32 debug DLL along with the non-debug version:
Currently, src/interfaces/libpq/win32.mak builds a statically-linked
library "libpq.lib", a debug dll "libpq.dll", import library for the
debug dll "libpqdll.lib", a release dll "libpq.dll", import library for
the release dll "libpqdll.lib". To avoid naming clashes, I would make
the debug dll and import libraries "libpqd.dll" and "libpqddll.lib".
Basically, the debug build uses the cl flags: "/MDd /D _DEBUG", and the
release build uses the cl flags "/MD /D NDEBUG". Usually the debug
build has a "D" suffix on the file name, so for example: