"Missing C library: pq" on Windows 7

[WillSewell]

I get this error even though I have PostgreSQL installed. I have tried cabal install --extra-lib-dirs="C:\PostgreSQL\include\libpq\" postgresql-simple which contains libpq-fs.h, but still no luck.

Here is the full error:

Configuring postgresql-libpq-0.9.0.1...
setup.exe: Missing dependency on a foreign library:
* Missing C library: pq
This problem can usually be solved by installing the system package that
provides this library (you may need the "-dev" version). If the library is
already installed but in a non-standard location then you can use the flags
--extra-include-dirs= and --extra-lib-dirs= to specify where it is.
Failed to install postgresql-libpq-0.9.0.1

[lpsmith]

Sorry for not seeing this until now; gmail has decided to start filing github notices under "promotions". >:o

I can't help too much, as I don't really use Windows and I have not compiled or used postgresql-libpq on Windows myself. However, you might find these instructions helpful: lpsmith/postgresql-simple#66

[WillSewell]

Thank you. I will try that out.

[joozek78]

I see that it's old, but I recently encountered the same problem. I had to have both libpq.dll and pg_config in my build dir.
It would be nice to hint that in error message. It's especially misguiding that exe is required when error message states that C library is missing