Memory corruption doesn't always trigger segfaults. I don't believe it will be obvious why some random other part of your program will start giving intermittent errors even if it is in Rust.
In Rust, or any other systems programming language with unsafe code blocks, all the way back to JOVIAL and ESPOL, one can search for those code blocks.
At very least they provide an initial searching point.
On C, C++ and Objective-C, any line of code is a possible cause for memory corruption, integer overflow, or implicit conversions that lead to data loss.
This is starting from the point of knowing it is a memory corruption issue though. From my experience, memory corruption usually manifests in logic or data behaviour changes. In a Rust program you'd probably spend a few days pulling your hair out trying to understand why some data structure doesn't do what it's supposed to before considering that it's one of the unsafe blocks.