A total memory limit for a process will limit the impact a single failure will have on the rest of the system. This is a reasonable precaution.

On my Debian GNU/Linux box I can call

ulimit -v 10000
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in the shell before starting my program and it will no longer be able to use more than 10000 Kilobytes of virtual memory.

However, that is not all I wanted. I would like to be able to stop processing the input file as soon as its contents are known to be malformed and take whatever evasive action is most appropriate. This would rule out plainly crashing in many cases.