This is largely a matter of personal preference, and this is probably even changing over time: 10-20 years ago, I didn't care much about -Wall (in various languages/compilers) too much, but this has changed with experience in tons of projects: Basically each and every warning turned into a bug sooner or later, with very, very few exceptions. So I'm basically a hardcore -Wall-clean-fanatic nowaydays. :-) Not using -Wall doesn't make the problems go away, you only discover them much, much later, probably when your SW is shipped to your client.

So whatever is done, it should be easily be possible to be -Wall-clean, which basically means more control over warnings. Especially important are one-shot things like the usual C/C++'s NOLINT ("I know what I'm doing here, really!") comments, which make it possible to be extremely fine-grained about warnings.

Warnings from compilers are just like people crying for help: If you see them too often, you get used to them and ignore them, which in the long run is bad for all parties involved...