Changes to Get_Settler_Contaminants function in atContaminants.c

[hmorzaria]

Justification

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Please describe the importance/impact of the problem and a description of how the changes in this pull request will address, resolve or improve the problem.

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Fixes issue #69 segmentation fault in flagmaternaltransfer

Types of changes

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• [ X] Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Other change (if none of the other choices apply)

Further comments

Identified a but when flagmaternaltransfer was turned on and all groups were turned on in the Puget Sound model (a previous run with a subset of groups had run), triggering a segmentation fault. Valgrind identified that the issue were multiple uninitialized values in atContaminants.c in function Get_Settler_Contaminants and in atmovement.c in function Ecology_Total_Verts_And_Migration.
Used Valgrind output to work through the errors, defined several variables and moved some of the code to earlier spots so the variables have values before going into the functions.

• [ X] I've created an issue
• This is NA