On a typical Linux box, overcommit and eager or confused OOM killer will ruin your day anyway.

For no_std style work where running out of memory is actually a hard limit, you have two choices:

1. disable the global allocator and use APIs that take Allocator, to force yourself to only consume APIs that can return errors from allocation. (The ergonomics aren't always great, and fattening all types with a pointer to Allocator isn't great; might be able to use a zero-sized Allocator, with trickery. Say goodbye to many libraries.)

2. use static analysis and try to avoid ever hitting a code path like Vec::with_capacity that doesn't return a Result. Make sure the tooling also analyses your dependencies. (Tooling for the static analysis is painful. And still, say goodbye to many libraries.)

I do wish there were more conveniences for alloc-can-fail APIs, like the failable version of Vec::push needs both try_reserve and push_within_capacity (nightly only).