tmp/tmp16vflz9s/{from.md → to.md}
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### [[basic]]: basics <a id="diff.cpp17.basic">[[diff.cpp17.basic]]</a>
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**Change:** A pseudo-destructor call ends the lifetime of the object to
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which it is applied. **Rationale:** Increase consistency of the language
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model. **Effect on original feature:** Valid ISO C++17 code may be
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ill-formed or have undefined behavior in this International Standard.
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[*Example 1*:
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``` cpp
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int f() {
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int a = 123;
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using T = int;
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a.~T();
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return a; // undefined behavior; previously returned 123
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}
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```
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— *end example*]
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**Change:** Except for the initial release operation, a release sequence
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consists solely of atomic read-modify-write operations. **Rationale:**
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Removal of rarely used and confusing feature. **Effect on original
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feature:** If a `memory_order_release` atomic store is followed by a
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`memory_order_relaxed` store to the same variable by the same thread,
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then reading the latter value with a `memory_order_acquire` load no
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longer provides any “happens before” guarantees, even in the absence of
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intervening stores by another thread.
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