how to use modelsim-altera simulate rom with mif initial file

hi everyone:

1. i use quartus 16.1

2. i add a rom in my project, and use *.mif file to initial the rom

3. in modelsim, the following error shows:

Error: MIF contains illegal characterï

i do not know what ï is

i check the altera_mf.vhd in modelsim, it seems like the error comes from

report "MIF contains illegal character" & m_line_buf(m_line_buf'low)

but i can not figure out what m_line_buf(m_line_buf'low) is

4. when i download my design to the board, it works , so i think the *.mif file is right