[Bug c/91232] Adding -fPIC with optimization level > 0 resulting a busy hang in my program

[bharath.appali at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91232

--- Comment #9 from bharath appali <bharath.appali at gmail dot com> ---
(In reply to Richard Biener from comment #5)
> It's the 0 - src computation that invokes undefined behavior and things go
> downhill from there.  Use 0 - (uint32_t)src here.

Can I please have any pointers which could explain why that particular
computation is invoking an undefined behaviour ? and also I'm interested to
know why this kind of behaviour is not seen when compiled with earlier gcc
versions.

Thanks in advance