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0 pointstialaramex2mo ago0 comments

It's trickier than it looks because C has mutable aliases. So, in C our bounds check might itself be a data race! Make sure you cope

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4 comments · 2 top-level

jstimpfle2mo ago· 2 in thread

Bounds checks have nothing to do with data races. GP is right, you can add bounds checks. Either using macros or (in C++) with templates and operator overloading.

tialaramexOP2mo ago

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.

jstimpfle2mo ago

True, but you do incur potential data races _everywhere_. There's no relation to bounds checking specifically.

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uecker2mo ago

Depending on what you are doing, yes. But the statement I responded to "your only choice is crash" is certainly wrong.

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