ld warning on Mac OS X

[Josef Sachs]

When I build julia on Mac OS X, I get the following.

ld: warning: object file (/Users/sachs/src/julia-master/usr/lib/julia/sys.o) was built for newer OSX version (15.5) than being linked (10.7)

What explains this, and is there a way that I can eliminate it?
I am running El Capitan (10.11.5), Darwin Kernel Version 15.5.0.
(You can probably tell that I do not compile a lot of things on Mac OS X.)

Thanks.

[Yichao Yu]

https://github.com/JuliaLang/julia/issues/14182
It's a upstream bug in llvm according to Jameson.

>
> Thanks.