about post simulation for dcfifo of megafunction

When doing post simulation with modelsim se, one runs well ,the other dosen't.

The projects in the attachments have the same function, except fifo_megawithflag.qar outputs some internal signals (clk_monitor, temp_out and flagout).

Do these signals affect the real function? When simulating fifo_megawithflag.qar, no data is read out from fifo.

Can anyone help simulate these two projects and tell me why these two projects have different simulating results?

THank you!