[diff.expr] Strike line in example that is UB in C23 - #9249
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In C23, "p + 0" is undefined behavior if p is a nullptr, regardless of whether the result is dereferenced.
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The two other lines in the example are sufficient exposition for the C incompatibility we wish to highlight. |
eisenwave
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Sep 8, 2026
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Yeah, that makes sense. Keeping the deleted line would be somewhat misleading because the UB happens earlier, so that line isn't really demonstrating what the example is meant to be about.
One might ponder whether it makes sense to keep the line for C2y (since adding 0 to null would be fine), but I don't think this line is crucial for that purpose either.
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@tkoeppe , you're next. |
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In C23, "p + 0" is undefined behavior if p is a nullptr, regardless of whether the result is dereferenced.
Fixes #9248