You are very right. With linker maps, debug symbol files etc. we can get a good handle on what went wrong.

> People would often leave some memory areas (typically circular buffers) with debug values that would be useful in debugging. They'd never be used anywhere in the program, unless the programmer had to poke around manually.

In one Linux-based system i worked on, they had an area of memory between the heap and the stack where shared libraries are typically mapped in, sectioned off as a circular buffer via linker scripts for each module which was then used for all sorts of logging. A separate process would also map this memory area to provide a UI and also to write to disk. It was pretty neat and worked great.