debug option provided by gcc10: -fanalyzer

[d-a-v]

-fanalyzer option is useful and currently gives insights on code in master.
Compilation is however slower when using it.
Should we add a new enable option in the generic board menus ?
Or a debug option (that would be available for all boards) ?

related: new option -Wstack-usage= described in #7398

[earlephilhower]

My thought is "yes" for stack-usage, but "no" for -fanalyzer.

The reason is that in my experience fanalyzer gets confused a lot, both in the core and in the libs, and you end up with way more junk dumps than is reasonable. It also isn't clean on the core, so unless we mop up the ~30 spots it doesn't like then any user code catches would be hidden in that.

Stack-usage is a pretty simple and clean check, though, and only complains in 3-4 spots that we can (should) easily fix.