The placement new operator enables the programmer to specify the memory in which the object being instantiated will be allocated. A problem may arise when such a pointer is pointer to this memory is misaligned with the underlying architecture alignment restrictions. On several RISC architectures such as PowerPC or on IA64 (Itanium) or Intel (IA32) CPUs which were configured to fault on unaligned access, access to unaligned objects might cause the program to terminate abnormally.
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