Turning warning into errors

[Sébastien Hinderer]

Dear all,

We recently noticed a few undefined variables in our makefiles.
We would like to use --warn-undefined-variables to track them, e.g. on
our CI infrastructure, but we find it problematic that the warning can
not be turned into an error.

Am I correct that there is currently no way to achieve this and, if so,
am I correct that it is a deliberate choice not to provide this featur?
In that case I'd be curious about why this has been decided.

Is there any other known approach to deal with this?

In particular, has somebody ever tried
https://github.com/mrtazz/checkmake
?

Many thanks in advance for any help,

Sébastien.