c - How is negative zero used in this context? -

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struct in_addr ipv4;  ipv4.s_addr = (uint32_t)(-0)

that's strange, arithmetic implemented through two's complement don't have negative representation of 0.

in one's complement version negative 0 instead stored 0xffffffff have 255.255.255.255 when converted ipv4 address after cast unsigned int.

while in normal architecture using -0 cast unsigned int should give 0x00000000.


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