The call stack in basically every programming environment is a virtual memory system with overcommit and allocation that never returns errors.
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Only if you misuse it as such by performing the cursed operation known as recursion.
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Linux kernel will also lazily map in the main thread stack even with overcommit disabled. Runtime has to do something about that during initialization if it wants to guarantee that a certain amount can be used later. An error can occur simply when you reach deepest stack usage.
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i.e. read a byte from each page just past the desired limit and install an actual guard page/region rather than relying on the magical automatically growing guard region it usually provides. Only thing I have seen doing this is ART for reliably throwing stack overflow exception.
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-fstack-clash-protection does the first bit — read a byte from each page. That's ensures SIGSEGV over UB.
If you have neither that nor proven static bounds on stack sizes, it seems unlikely a program logic can be sound; (with that it'd be sound up to stack overflows).
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-fstack-clash-protection just prevents you from jumping over a guard page/region. It doesn't map in the whole stack before you start using it. It doesn't prevent dying because of memory allocation failure with overcommit disabled when you call a function because mapping fails.
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I was focused on "reliably throwing stack overflow exception", but it sounds like you don't want to get that on OOM? I'm mostly concerned with avoiding UB (tho I'm not on Linux and overcommit isn't a thing for us).
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Look back at mobile.twitter.com/DanielMicay/st. Linux has support for disabling overcommit but a lot of programs will still have a form of dynamic memory allocation failure they aren't able to handle unless they reserve the main thread stack space they need up front and handle an error.
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Replying to @RichFelker and @pcwalton
Linux kernel will also lazily map in the main thread stack even with overcommit disabled. Runtime has to do something about that during initialization if it wants to guarantee that a certain amount can be used later. An error can occur simply when you reach deepest stack usage.