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Hi, > + /* size_t is unsigned so the behavior on overflow is defined. */ > + bytes = n * elem_size; > + if (bytes / elem_size != n) { > + MALLOC_FAILURE_ACTION; > + return 0; > + } This is of course correct, but some (long) time ago I've measured that the cost for the division is quite noticeable, for say, the very common calloc(1, small_size). I've given up on being able to do this fast _and_ portably. Do we already have some system-specific mechanism to detect the rare overflow case for a 32bit-multiplication without having to perform a division? Regards, Wolfram.
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