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Re: "Uninitialized array" warnings by c++ with -O2


On 07/06/17 10:15, Kirill Yu Berezin wrote:
> My question is. Is this an expected behaviour or I must report a bug ?

It's not a bug: your code displays undefined behaviour: you're casting
a pointer to struct udp_pseudo fields to an array of uint16_t.  This
is never well-defined in C++, but if you really want to do this kind
of thing, use -fno-strict-aliasing.

See also
http://www.microhowto.info/howto/calculate_an_internet_protocol_checksum_in_c.html

-- 
Andrew Haley
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
EAC8 43EB D3EF DB98 CC77 2FAD A5CD 6035 332F A671


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