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Uninitialized variables

Benjamin_K_1
Beginner
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Is there a way to have ifort look for uninitialized variables (maybe a debugging flag)?

Thanks - Ben

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jimdempseyatthecove
Honored Contributor III
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In Debug build there is a runtime option to check for use of un-initialized variables.

-QTrapuv and/or -RTCu

Jim Dempsey

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Steven_L_Intel1
Employee
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No, not -Qtrapuv - pretend that doesn't exist. -check uninit will do some checking. The Static Analysis feature of Fortran Studio XE can do a good job of this.

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Casey
Beginner
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jimdempseyatthecove wrote:

-QTrapuv

This won't tell you that you have uninitialized variables but will likely cause runtime errors or garbage program output if you do have them. This flag causes your variables to start out with garbage values that will propagate through your code if you are not initializing them before use. 

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Steven_L_Intel1
Employee
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-Qtrapuv isn't useful. What it does is cause floating point variables to be initialized to an "unusual value". It is not a NaN or anything else that would trigger an exception. I think using this reduces the chance of your finding errors and recommend against using it.

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