I have a FORTRAN application in which I am experiencing a large difference in compile times between using different versions the Intel FORTRAN compiler. Using 11.1 the compilation takes hours (2-4 on average), using 12.1 the compilation takes minutes (5-10 on average). Both resulting applications behave the same, and deliver the same output. What could be possibly causing the extreme difference in compile time? I understand the may be a very vague questions with many possible answers. I'm just looking for general direction on how to resolve the issue, if possible.
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