* Tom Callaway:
So, R links with rt if this configure check succeeds:
AC_CHECK_LIB(rt, clock_gettime)
Sure enough, on aarch64 and ppc64le, there is no clock_gettime in
librt.so.1. I'm not sure _why_, but there is probably a good reason.
Hah!
We moved clock_gettime to libc.so.6 in glibc 2.17, so that it is
available without -lrt as well. But we forgot to turn the legacy
definitions into compatibility symbols, so they are still being picked
up with -lrt. This should be easy enough to fix.
Thanks,
Florian