FYI, here is what happened. After I upgraded from IPP 7.0 update 1 to IPP 7.0 update 6 (the latest one), without doing anything else, the problem dissapeared. All my IPP codes now can be compiled smoothly. All I did was to install the new IPP, and nothing else.
I suspect this is a bug from IPP 7.0 update 1 that has something to do with the incompatibility between libthread in Linux and libiomp5 in IPP?