10.13 ntp build failure (undefined symbols)

[Rainer Müller]

On 2017-10-03 22:26, Joshua Root wrote:
> Apparently Apple's linker doesn't recognise common symbols in static
> libraries as being defined. Workaround would be to initialise the
> variables somewhere or use -fno-common. Ideally don't use common linkage
> at all, have one file that each global actually lives in and have all
> other declarations be extern.

I remember this as a long-standing issue. I filed rdar://problem/9870713
for this in 2011, but never got a response from Apple. As a workaround
you could apply 'ranlib -c libntp.a' before linking.

I am a bit puzzled why this problem only occurs on 10.13 High Sierra,
which I could reproduce. However, ntp just builds fine on 10.12 Sierra,
with both systems running Xcode 9. Seems like a regression to me.

Rainer