Dealer’s choice. Reallocating stack return values (ideally with compiler support) and aborting on stack overflow isn’t a bad combination, since you get decent guarantees about whether a function has enough memory to run until either completion or the next function call. POSIX’s out-of-stack-space behavior isn’t terrible here either.

As for DRAM: if by “exception loading page” you mean an OOM, then have malloc use the same error reporting system. If you instead mean “some other failure faulting/fetching a page from main memory”, well … crash? I don’t know of any platform that has semantics for handling that condition. Hardened spacecraft OSes, maybe?