There are new failures in some of the extensions starting from Oct 19 (sorry, I noticed just now). We did not change the extensions code in that period of time, so it must be due to some Slicer changes.
Specifically, DCMQI and PkModeling started to fail (both are superbuild-style extensions).
@jcfr I did not test, but on the surface at least (the error happens in the fixup_extension step, the specific failure is about not being able to locate the extension dir, the error happens in the superbuild extensions) it looks like this commit is to blame:
Also, Slicer extension build system has been improved to help extension developer diagnose the problem at configuration time. An configure like the following will now be reported:
NameOfExtension: Variable CPACK_INSTALL_CMAKE_PROJECTS is expected to be set.