[Bug c/55967] rightshift an unsigned value (X) by it's number of bits does not always yield 0, when X is an unsigned that's leftshifted by it's number of bits and offset

[b1314361 at rmqkr dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55967

JoeSoe <b1314361 at rmqkr dot net> changed:

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--- Comment #3 from JoeSoe <b1314361 at rmqkr dot net> 2013-01-15 07:15:41 UTC ---
Hi Jakub Jelinek,

can you elaborate?
What does it mean to say: "The testcase is invalid, the bug is only on the side
of the testcase." ?

Why does gcc not yield the "graceful/expected" result, and why will no effort
be undertaken to make it yield the "graceful/expected" result?

For example: Is it because of optimizations, that would be removed, if it were
to yield the "graceful/expected" result??

In other words: what's the background on this?
Thanks.