VxWorks 24.03 (and probably earlier versions as well) implementation of `std::uninitialized_value_construct` is calling `placement new` for each element in passed range this way (simplified): ``` new (memPtr) T; ``` This is causing default-initialization, which for class type calls default constructor, but for non-class non-array types does nothing. This is the case for, for example, trivial classes, for which no constructor is called, leaving memory in random state. This is a bug in VxWorks standard library. To work around this problem, introduce q17memory.h header, which introduces `q17::uninitialized_value_construct`. This function is simply taken from std implementation on all platforms except VxWorks, where it's implemented in a standard-compliant way. Amends 33155f06bf5000c958a178689a2553391e155891. Task-number: QTBUG-115777 Change-Id: I1456c801334b50a9fc8b82cefb8c5d216b57923f Reviewed-by: Marc Mutz <marc.mutz@qt.io>