[diff.cpp11.basic] # Annex C (informative) Compatibility [[diff]](./#diff) ## C.5 C++ and ISO C++ 2011 [[diff.cpp11]](diff.cpp11#basic) ### C.5.3 [[basic]](basic "6 Basics"): basics [diff.cpp11.basic] [1](#1) [#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/compatibility.tex#L1995) **Affected subclause:** [[basic.stc.dynamic.deallocation]](basic.stc.dynamic.deallocation) **Change:** New usual (non-placement) deallocator[.](#1.sentence-1) **Rationale:** Required for sized deallocation[.](#1.sentence-2) **Effect on original feature:** Valid C++ 2011 code can 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 revision of C++, however, the declaration of operator delete might match a predefined usual (non-placement)operator delete ([[basic.stc.dynamic]](basic.stc.dynamic "6.8.6.5 Dynamic storage duration"))[.](#1.sentence-4) If so, the program is ill-formed, as it was for class member allocation functions and deallocation functions ([[expr.new]](expr.new "7.6.2.8 New"))[.](#1.sentence-5)