Does Rust expose call stack depth?

Question

Background information: I have a function that calls itself both directly and indirectly through other functions, and would like a cheap way to fail gracefully should the program run out of call stack. I could count calls manually, but I would like a more elegant and robust way of achieving this.

Is it possible to determine current call stack depth using stable Rust?

The only options I could find are:

1. Following the stack in ASM, but it requires unstable and is not portable.
2. Using a GNU libc extension (backtrace). However, backtrace is too wasteful and also not standard.

Answer 1

The stacker crate seems to provide the functionality you seek:

• A function to guarantee the amount of available stack
• A function to query the amount of remaining stack, which you could use to bail before the program actually stack-overflows

The library supports the Linux, Windows and macOS targets.