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The same fortran 77 code produce different results with different compilers

wyliao
Beginner
‎11-01-2005 10:59 PM
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Hello,
I am a newcomer here, hope can get help from you guys.
Recently, I am bothered by a strange and weird problem.
I have fortran 77 code, see test.f, if I compile it with ifort and run it, I got something, but if I change to other compilers, such as g77 and lahey, I got different results.
The difference is kind of large, for instance, the difference is about 10 percent between ifort and g77, and 5 percent between ifort and lahey. Can anybody tell me what is the possible reason? Thanks

-Liao
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TimP
Honored Contributor III
‎11-01-2005 11:14 PM
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The most common reason is that you have un-initialized variables, or array subscript over-runs. Each of these compilers has options to help diagnose them, for example ifort -C You could look up previous discussions on similar topics on this forum.
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