Dynamics AX 2012: orig() method fails on derived tables

Just found a bug in the table inheritance feature (kernel 6.0.1108.5781).

If you have a base table A with field B, and a derived table C with field D, then C.orig().B will return a strange value (or nil, depending on the field type).

In order to get the correct value, you will need to downcast C to A, and then call A.orig().B.

This is the job that reproes the issue:

static void reproOrigBug(Args _args)
{
    CompanyInfo     companyInfo;
    DirPartyTable   dirPartyTable;
 
    select firstOnly companyInfo;
 
    info(companyInfo.orig().DataArea);
    info(companyInfo.orig().Name);
 
    dirPartyTable = companyInfo as DirPartyTable;
    info(dirPartyTable.orig().Name);
}

And this is the output:


I will report the issue to MS Support.