[basic.stc.dynamic.deallocation]
Change: New usual (non-placement) deallocator.
Rationale: Required for sized deallocation.
Effect on original feature: Valid C++ 2011 code could declare a global placement allocation function and
deallocation function as follows:
void* operator new(std::size_t, std::size_t); void operator delete(void*, std::size_t) noexcept;
In this International Standard, however, the declaration of operator delete might match a predefined usual (non-placement) operator delete ([basic.stc.dynamic]). If so, the program is ill-formed, as it was for class member allocation functions and deallocation functions ([expr.new]).