The only way to make Rust segfault is by performing unsafe operations.

Challange accepted. The following Rust code technically segfaults:

fn stackover(a : i64) -> i64 {
    return stackover(a);
}


fn main() {
    println!("{}", stackover(100));
}

A stack overflow is technically a segmentation violation. At least on linux the program recives the SIGSEGV signal. This compiles and I am no rust dev but this does not use unsafe code, right?

While the compiler shows a warning, the error message the program prints when run is not very helpfull IMHO:

thread 'main' has overflowed its stack
fatal runtime error: stack overflow
[1]    45211 IOT instruction (core dumped)  ../target/debug/rust

Edit: Even the compiler warning can be tricked by making it do recusion in pairs:

fn stackover_a(a : i64) -> i64 {
    return stackover_b(a);
}

fn stackover_b(a : i64) -> i64 {
    return stackover_a(a);
}

fn main() {
    println!("{}", stackover_a(100));
}