Compiling psqlODBC on CENTOS 7 gives me errors in connection.c - undeclared identifiers - postgresql

Question

So i'm stuck again.
What I want to do: access a postgreSQL database via database link from Oracle (12.1 - yes, I know it's old ...).
Oracle is running on Centos 7.
Initially I did a
yum -y install postgresql-odbc
yum -y install unixODBC
and was able to access postgreSQL (running on another machine).
But it didn't work for UTF-8 data. Got a hint that this might be due to an old version of unixODBC so I decided to compile from source (as the centos package is rather old).
Compiling and installing unixODBC worked without a hassle:
wget http://www.unixodbc.org/unixODBC-2.3.11.tar.gz
tar xzf unixODBC-2.3.11.tar.gz
cd unixODBC-2.3.11/
./configure
make
make install
But compiling psqlODBC is where it's at:
yum install postgresql
yum install postgresql-devel
wget https://ftp.postgresql.org/pub/odbc/versions/src/psqlodbc-13.02.0000.tar.gz
cd psqlodbc-13.02.0000/
./configure
make
...
Make gives me the following output:
[root#tukanbox psqlodbc-13.02.0000]# make
make all-am
make[1]: Entering directory `/root/psqlodbc-13.02.0000'
/bin/sh ./libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I/usr/local/include -I/usr/include -I/usr/include/pgsql/internal -DUNICODE_SUPPORT -g -O2 -Wall -MT psqlodbcw_la-connection.lo -MD -MP -MF .deps/psqlodbcw_la-connection.Tpo -c -o psqlodbcw_la-connection.lo `test -f 'connection.c' || echo './'`connection.c
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I/usr/local/include -I/usr/include -I/usr/include/pgsql/internal -DUNICODE_SUPPORT -g -O2 -Wall -MT psqlodbcw_la-connection.lo -MD -MP -MF .deps/psqlodbcw_la-connection.Tpo -c connection.c -fPIC -DPIC -o .libs/psqlodbcw_la-connection.o
connection.c: In function 'handle_pgres_error':
connection.c:900:45: error: 'PG_DIAG_SCHEMA_NAME' undeclared (first use in this function)
errschemaname = PQresultErrorField(pgres, PG_DIAG_SCHEMA_NAME);
^
connection.c:900:45: note: each undeclared identifier is reported only once for each function it appears in
connection.c:901:44: error: 'PG_DIAG_TABLE_NAME' undeclared (first use in this function)
errtablename = PQresultErrorField(pgres, PG_DIAG_TABLE_NAME);
^
connection.c:902:45: error: 'PG_DIAG_COLUMN_NAME' undeclared (first use in this function)
errcolumnname = PQresultErrorField(pgres, PG_DIAG_COLUMN_NAME);
^
connection.c:903:47: error: 'PG_DIAG_DATATYPE_NAME' undeclared (first use in this function)
errdatatypename = PQresultErrorField(pgres, PG_DIAG_DATATYPE_NAME);
^
make[1]: *** [psqlodbcw_la-connection.lo] Fehler 1
make[1]: Leaving directory `/root/psqlodbc-13.02.0000'
make: *** [all] Fehler 2
Wondering where to declare these undeclared idenifiers. What does it want to know here? How to solve it?

Answer 1

No answer to the problem of not being able to compile - but an answer to the original problem that the original packages didn't work for UTF8:
https://www.postgresql.org/message-id/OFA166DBFD.19742AF7-ONC1257B6A.005692E6-C1257B6A.0056F890#lladro.net
This has to be done in the database as sysdba:
select fds_class_name from HS_FDS_CLASS;
select * from hs_class_caps where upper(CAP_DESCRIPTION) like '%NCHAR%' and FDS_CLASS_NAME ='ODBC12.1.0.1.0_0017';
exec DBMS_HS.ALTER_CLASS_CAPS('ODBC12.1.0.1.0_0017' , 564, 'ODBC12.1.0.1.0_0017', 564,131071, NULL, NULL);