AMD64 distribution produces unresolved symbol error when attempting to
use libmyodbc.so driver.

1. Install mysql-server, start mysqld service
2. Install ODBC packages
3. Configure odbc.ini / odbcinst.ini as follows:

% cat /etc/odbc.ini
[dbconn]
driver=MySQL
Description=MySQL
Server=localhost
% cat /etc/odbcinst.ini
# Example driver definitinions
#
#

# Included in the unixODBC package
#[PostgreSQL]
#Description     = ODBC for PostgreSQL
#Driver          = /usr/lib/libodbcpsql.so
#Setup           = /usr/lib/libodbcpsqlS.so
#FileUsage       = 1


# Driver from the MyODBC package
# Setup from the unixODBC package
[MySQL]
Description    = ODBC for MySQL
Driver         = /usr/lib64/libmyodbc.so
Setup          = /usr/lib64/libodbcmyS.so
FileUsage      = 1

4. isql -v MySQL-test test
[unixODBC][Driver Manager]Can't open lib '/usr/lib64/libmyodbc.so' :
/usr/lib64/libmyodbc.so: undefined symbol: _dig_vec
[ISQL]ERROR: Could not SQLConnect

_dig_vec is provided by /usr/lib64/mysql/libmysqlclient.so.10.  If I
had to guess, I'd say this problem has to do with incorrect settings
of library search paths (lib x lib64).

I have a strong suspicion on unixODBC.  It doesn't seem to be
lib64-compatible.  Not only does the default .ini file mention
/usr/lib, that's unlikely to work on a lib64 box, but also:

% strings /usr/lib64/libodbc.so.1 | grep /lib
/usr/lib64
%s/libodbcinstQ%s
/lib:/usr/lib
/lib:/usr/lib

The occurrences of /lib:/usr/lib feel like a strong indication that it
might fail to locate libraries.  A similar configuration (with
s/lib64/lib/g) works on an ia32 box.