Segmentation Error when switching from linux to mac

I could compile and run a code on linux clusters without a problem. Now I want to run the same code on a brand new iMac, but I receive segmentation error when I run the same code. On linux I had to use the following flag:

FC=ifort
FFLAGS= -mcmodel medium -shared-intel

but because -mcmodel is not supported, I have to comment it out. Can this be the reason of this problem?Is there any alternative for MACs?

I have tried the following flags and non of them works:

FFLAGS= -heap-arrays

or

FFLAGS= -heap-arrays 10

or

FFLAGS= -Wl,-stack_size -Wl,10000000

PS: I just bought the iMac and I've installed the last version of intel fortran parallel studio.