Internal error 99080501 using "absolute" for an "out" parameter

Summary

Fatal: Internal error 99080501 when saying "array of Int64 absolute Unsigned" where "Unsigned" is a parameter.

System Information

Linux, x64. FPC trunk from last November.

Steps to reproduce

{$MODE OBJFPC}  
{$MODESWITCH ADVANCEDRECORDS+}
program test;

procedure Resolve(out Unsigned: array of QWord);
var
   Signed: array of Int64 absolute Unsigned;
begin
   SetLength(Signed, 0);
end;

begin
end.

What is the current bug behavior?

test.pas(9,4) Fatal: Internal error 99080501
Fatal: Compilation aborted

What is the expected (correct) behavior?

Code should compile and run without issue.