Seg fault on PQconnectdb

Hi everyone,

I'm trying to use libpq in my application, but it crashes with a seg fault
when trying to connect. The call stack is as follows : malloc_consolidate <
_int_malloc < malloc < makeEmptyPGconn < PQconnectStart < PQconnectdb < my
own application.

I have no clue as to what causes this. Sample programs that only do a call
to PQconnectdb work fine. My application uses a complex build script so I
suspect it may be a compiling or linking problem, but there are no errors
reported, and ldd points to the correct version of libpq.so.

I've tried googling but could not find anything useful. I would really
appreciate some help. Thanks in advance!

(English is not my first language so I apologize if there are mistakes or
I'm not being very clear.)

Joe L.F.