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OpenMP compiler settings

a_leonard
Novice
‎09-09-2013 02:09 PM
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I have a program that produces different results when compiled with /Qopenmp, even with no OpenMP directives in the source code.  I have already fixed a couple of variables that were not set before they were used and an array that was not declared the right size, but still have differences in some models.  These models may not be stable, but I'm trying to rule out any other complier settings that could change the results.  The help tells me that the OpenMP option also sets the automatic option.  Are there any other compiler settings that are changed by /Qopenmp?

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Steven_L_Intel1
Employee
‎09-09-2013 04:21 PM
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The /automatic option is the most likely cause of differences, as this uses stack-allocation instead of static allocation.  If you have uninitialized variables, this will change the program's behavior. There really aren't any other effects.

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