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Re:A simplified model of Fil-C by tialaramex on Wednesday April 22, 2026 @11:51AM (#47865390)
Alas, in C or C++ you have mutable aliasing, so I'm afraid you do incur a potential data race because your bounds might alias. Be careful out there.

Also remember that in C++ you may get a reference in these cases and if you keep that reference rather than using it immediately now you also have a potential TOCTOU race because the reference was only valid when you did the bounds check.

Re:A simplified model of Fil-C by jstimpfle on Thursday April 23, 2026 @11:04AM (#47876588)
True, but you do incur potential data races _everywhere_. There's no relation to bounds checking specifically.
Re:A simplified model of Fil-C by tialaramex on Friday April 24, 2026 @11:42AM (#47891788)
Ah, maybe I should have made the example clearer

With mutable aliasing the length might change even though the data you care about did not, and so adding the check means incurring a race which did not previously exist and which certainly the naive C programmer cannot see...

We can definitely mitigate this in the type system for most real world scenarios, but you don't mitigate problems you don't know about, so knowing is what's important.