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    Type:
Improvement
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    Resolution: Fixed
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    Priority:
Major - P3
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    Affects Version/s: None
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    Component/s: Concurrency
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    None
 
- 
        Fully Compatible
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        None
 
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        None
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        None
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        None
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        None
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        None
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        None
 
A deleted constructor would make a call like 
{{    _needsLock(stdx::lock_guard<stdx::mutex>(_mutex), _other);}}
fail.
Rationale is that depending on implementation, lock might or might not be held when _other is used.