Field SQL_DESC_COUNT should fit into a variable of type SQLSMALLINT. But
when retrieving this field of APD SQLGetDescField returns SQLINTEGER
value. So memory corruption is possible in application using psqlodbc
driver.
Also the function returns an undefined error code -8.
The mistake is located here
https://git.postgresql.org/gitweb/?p=psqlodbc.git;a=blob;f=pgapi30.c;h=ba0dd6d731bbccd81392def43ae9b10e9c013aef;hb=HEAD#l1240
Just replace 'ret = SQL_IS_SMALLINT;' with 'rettype = SQL_IS_SMALLINT;'.