I don't know of a common (or uncommon) function like this, though I think you could indeed implement it if you really want to (likely via AddVectoredExceptionHandler). It still requires explicitly telling the OS to commit just-in-time, so it's not "overcommitting". The closest built-in thing to this that I know of is PAGE_GUARD, which is internally used for stack extension, but that's all I can think of. The use cases for such a thing would be incredibly niche though—like kind of high-performance sparse page management where every single memory access instruction counts. Like maybe if you're writing a VM or emulator or something. Something that's only appropriate for << 1% of programs.