minimal backport of 8182299 build on OSX 10 + Xcode 8

[Andrew Haley]

On 7/4/19 2:22 PM, Simon Tooke wrote:
> In fact, I'd rather address runtime undefined behaviours first; fixing
> these often fixes compile-time warnings too.

Which reminds me: I'm hoping to raise the subject of Undefined
Behaviour in HotSpot at the OpenJDK Contributors' Meeting this
year. I'd like to have a blanket policy that all of it has to
go. There are a couple of exceptions for things that are undefined in
Standard C but defined in GNU C: these are OK, I believe.

-- 
Andrew Haley  (he/him)
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
https://keybase.io/andrewhaley
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