RQP-DEF-0177 error when running a Cognos report

Symptoms

RQP-DEF-0177 An error occurred while performing operation 'sqlPrepareWithOptions' status='-56'.

UDA-SQL-0115 Inappropriate SQL request.

UDA-SQL-0564 Deferred prepare could not be completed.

UDA-SQL-0564 Statement(s) could not be prepared. (SQLSTATE=42000, SQLERRORCODE=8180)

UDA-SQL-0564 Incorrect syntax near 'udfcode'. (SQLSTATE=42000, SQLERRORCODE=102)

SQL query contains comments starting with "--" or "/*".

Even though the query runs in Query Analyzer it fails in Cognos.

Remove the comments.