Compiler warning: Null pointer arithmetic has undefined behavior

skarupke / flat_hash_map

A very fast hashtable

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Compiler warning: Null pointer arithmetic has undefined behavior #28

Open cebtenzzre opened 5 years ago

cebtenzzre commented 5 years ago

unordered_map.hpp:425:46: warning: performing pointer arithmetic on a null pointer has undefined behavior if the offset is nonzero [-Wnull-pointer-arithmetic]
        *new_buckets = EntryPointer(nullptr) + ptrdiff_t(1);

That line looks harmless to me, but undefined behavior should be avoided if at all possible.