[convefefe]

Have done something similar, and it works, but ...

... the downside is that every time someone uses a different version of your normal compiler, or a different compiler, you have an unfortunately large chance of having the build fail because a new bit of code that previously was warning free is now determined to be warning-worthy.

Not a huge problem (and better than cultivating the habit of ignoring warnings), but it is a time cost that has to be paid now and again for committing to halting the build on a static analysis failure.

[nnethercote]

From the blog post:

"Set things up so that fatal warnings are off by default, but enabled on continuous integration (CI). This means the primary coverage is via CI. You don’t want fatal warnings on by default because it causes problems for developers who use non-standard compilers (e.g. pre-release versions with new warning classes). Developers using the same compilers as CI can turn it on locally if they want without problem."

[TD-Linux]

I think that's why TFA suggested only doing this in CI (with a known compiler version) and not for local builds.