[expr.unary.op] Add a note about dereferencing a dangling pointer#8130
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tkoeppe merged 2 commits intoJul 28, 2025
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Dereferencing a dangling pointer to an object is valid; the resulting
lvalue can be used in limited ways as per [basic.life] p8.
Add a non-normative note linking the two sections together.
The original wording ("If the operand points to an object...") misled
me; I assumed the object would have been within its lifetime, and
therefore dereferencing a dangling pointer would be UB, but the kind
folks at CWG explained the correct interpretation to me -- a pointer
can "point to an object" even outside that object's lifetime.
jensmaurer
reviewed
Jul 28, 2025
Co-authored-by: Jens Maurer <Jens.Maurer@gmx.net>
jensmaurer
approved these changes
Jul 28, 2025
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Dereferencing a dangling pointer to an object is valid; the resulting lvalue can be used in limited ways as per [basic.life] p8.
Add a non-normative note linking the two sections together.
The original wording ("If the operand points to an object...") misled me; I assumed the object would have been within its lifetime, and therefore dereferencing a dangling pointer would be UB, but the kind folks at CWG explained the correct interpretation to me -- a pointer can "point to an object" even outside that object's lifetime.