Update CMakeLists.txt: set minimum cmake version to 3.18

[climbfuji]

All in the title. Resolves #610

User interface changes?: No

Fixes: #610

Testing: only CI testing needed

Related to NCAR/ccpp-physics#1101

[gold2718]

👍

[mkavulich]

@climbfuji Can you direct this commit to the develop branch instead of the main branch please?

[climbfuji]

@climbfuji Can you direct this commit to the develop branch instead of the main branch please?

May I ask why? This is intended to go in asap instead of waiting for the lengthy process of validating the capgen changes. It's a simple fix needed for UFS (and other models will benefit from it). I can easily cherry-pick the commit and create a parallel PR for develop if you think that is helpful/more in line with the (not-yet-finalized) development workflow.

[mkavulich]

@climbfuji Sorry, I had assumed the target of main was unintentional, since this didn't seem to be an urgent bug fix. I'll add an item to today's agenda to discuss PRs directly to main, since we don't currently cover that in our development rules.

[mkavulich]

@climbfuji at today's meeting we decided to go ahead and merge this PR as-is, but we'll need to have a discussion about the protocol for making commits directly to main at a future meeting.

[climbfuji]

@climbfuji at today's meeting we decided to go ahead and merge this PR as-is, but we'll need to have a discussion about the protocol for making commits directly to main at a future meeting.

Technically speaking we should have tested this with the UFS (combine with their next PR), but ok. @DusanJovic-NOAA Can you update the ccpp-framework submodule pointer in your next PR, please? Or in any other PR that involves fv3atm that goes in next. Thanks very much.

Looking forward to the "merge to main" discussion. This is going to happen more often, because develop is de-facto dev-capgen at the moment (and will become dev-ncarsima or something like that in the future). Consolidated updates from NRL's internal develop branch will all come to main directly.