Below is a very small sample program.
Compiling it using a recent trunk version of fpc (younger than 2 weeks) does not give any hints.

If I uncomment the "var" block, there will be a hint, about TBar being deprecated.

But the usage of TBar in the procedure declaration is not hinted at. Is that intended? known to be a bug? not yet know (worth a report)? ----

program Project1;
{$mode objfpc}{$H+}
type
   TBar = Array of Integer deprecated;
//var
//  Bar: TBar;
procedure Foo(ABar: TBar);
begin
   writeln(ABar[0]);
end;
begin
   Foo(nil);
end.