>>364
この意味がわからないのか?
http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#1438
The current Standard says that any use of an invalid pointer value produces
undefined behavior (3.7.4.2 [basic.stc.dynamic.deallocation] paragraph 4).
This includes not only dereferencing the pointer but even just fetching its value. The reason for this draconian
restriction is that some architectures in the past used dedicated address registers for pointer loads and stores
and they could fault if, for example, a segment number in a pointer was not currently mapped.