Bugfix #2106 main_v10.1 gcc

[JohnHalleyGotway]

Expected Differences

• Do these changes introduce new tools, command line arguments, or configuration file options? [No]
  
  If yes, please describe:
  

• Do these changes modify the structure of existing or add new output data types (e.g. statistic line types or NetCDF variables)? [No]
  
  If yes, please describe:
  

Pull Request Testing

• Describe testing already performed for these changes:
  

Tested the compilation of MET with GCC 9 via Docker.

1. Cloned MET repo and checked out the feature branch here:
   /Volumes/d1/projects/MET/MET_development/bugfix_2106/MET-bugfix_2106_gcc
2. Ran this Docker command to mount the MET repo into the unit_test_gcc9 image:

docker run --name gcc9_test -it \
-v /Volumes/d1/projects/MET/MET_development/bugfix_2106/MET-bugfix_2106_gcc:/met/MET-bugfix_2106_gcc \
dtcenter/met-base:unit_test_gcc9 \
/bin/bash

3. Inside the container, I sourced the environment and compiled MET:

cd /met/MET-bugfix_2106_gcc/met
source ../scripts/environment/development.docker
./bootstrap
./configure --enable-grib2 --enable-modis --enable-mode_graphics --enable-lidar2nc --enable-python
make clean install test >& make.log

4. Confirmed that it now compiles using GCC9. Also note that GHA successfully compiles this feature branch.

• Recommend testing for the reviewer(s) to perform, including the location of input datasets, and any additional instructions:
  

Just review the code changes. You could go through all the compilation steps listed above, but compiling inside the container is actually really slow.
Recommend reviewing this at the same time as the PR for develop #2135.

• Do these changes include sufficient documentation updates, ensuring that no errors or warnings exist in the build of the documentation? [No]
  None needed.

• Do these changes include sufficient testing updates? [No]
  None needed.

• Will this PR result in changes to the test suite? [No]
  
  If yes, describe the new output and/or changes to the existing output:
  

• Please complete this pull request review by [Monday 4/11/2022].
  

Pull Request Checklist

See the METplus Workflow for details.

• Review the source issue metadata (required labels, projects, and milestone).
• Complete the PR definition above.
• Ensure the PR title matches the feature or bugfix branch name.
• Define the PR metadata, as permissions allow.
  Select: Reviewer(s)
  Select: Organization level software support Project or Repository level development cycle Project
  Select: Milestone as the version that will include these changes
• After submitting the PR, select Linked issues with the original issue number.
• After the PR is approved, merge your changes. If permissions do not allow this, request that the reviewer do the merge.
• Close the linked issue and delete your feature or bugfix branch from GitHub.

[georgemccabe]

It looks like these changes involve removing const from one of the arguments to a function, adding that variable to the list of shared resources for OMP, and adding dependency of the Z library to the plot_point_obs tool. Also, a environment file for running in Docker was added to easily compile and test using Docker.

I don't fully understand why these changes fixed the issue with compiling using GCC 9, but they do appear to preserve the output of the unit tests using GCC 8. If you are confident that the testing you performed using GCC 9 is sufficient, then I approve this PR.