For the first example, for C or C++ code gcc will catch the dangling reference/pointer and warn about it, and since my group normally turns on -Wall -Werror, it's an error. However, the analysis is local and not as powerful as Rust's borrow checker.

Try int* bug() { int longlived = 12; int* plonglived = &longlived; { int shortlived = 13; plonglived = &shortlived; } return plonglived; }

With gcc -Wall -Werror