create or alter procedure ppp as begin end;
recreate table ttt(qty int);
commit;

create or alter procedure ppp (qty integer default 0)
as begin
    if ( qty > 0 ) then
    begin
        insert into ttt(qty) values(:qty);
    end
end

Error Message:
----------------------------------------
SQL Parse Error:

Parameter name expected

[00544AE7] FIB.FIBError (Line 436, "FIB.pas" + 1) + $2C
[0053CD46] FIBQuery.TFIBQuery.PreprocessSQL (Line 3493, "FIBQuery.pas" + 136) + $13
[0053E08B] FIBQuery.TFIBQuery.SQLChange (Line 3885, "FIBQuery.pas" + 6) + $12
[0041CEF5] Classes.TStringList.Changed (Line 3283, "Classes.pas" + 1) + $14
[00D57BDD] DebugSP_New.TfrmDebugSP_new.ExecuteInsert (Line 1367, "DebugSP_New.pas" + 10) + $11
[00D58548] DebugSP_New.TfrmDebugSP_new.ExecuteStatement (Line 1513, "DebugSP_New.pas" + 24) + $5