RFR: 8145096: Undefined behaviour in HotSpot

John Rose john.r.rose at oracle.com
Fri Dec 18 04:38:45 UTC 2015

On Dec 17, 2015, at 2:31 AM, Andrew Haley <aph at redhat.com> wrote:
> I'm sure that it makes no sense ever to construct bitmasks using a
> signed type.  I am doing my best to be certain that I don't break
> anything.  I'll have a look to see if there is some way that I can
> change this to unsigned without changing behaviour.

This is more reason to avoid using the built-in C operators for bit-twiddling
and use macros or inlines instead.  See globalDefinitions.hpp, near right_n_bits.
(Which is wrong, but less wrong than writing built-in C operators.)

— John

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