std::pointer_safety
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                    |   Defined in header  <memory>
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|   enum class pointer_safety {      relaxed,  | 
 (since C++11)  (removed in C++23)  | 
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The scoped enumeration type pointer_safety lists the pointer safety modes supported by C++.
Enumeration constants
  pointer_safety::strict
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Only safely-derived pointers (pointers to objects allocated with new or subobjects thereof) may be dereferenced or deallocated. Garbage collector may be active. | 
  pointer_safety::preferred
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All pointers are considered valid and may be dereferenced or deallocated. A reachability-based leak detector may be active. | 
  pointer_safety::relaxed
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All pointers are considered valid and may be dereferenced or deallocated. | 
See also
|    (C++11)(removed in C++23)  | 
  returns the current pointer safety model  (function)  |