CMS Pull requests tests failed when we try to use ROOT head of v6-14-00-patches or master branch. CMSSW build fails when we dry to load CMS plugins during the build. Memory consumption is very high and build process failed with error [a] (bad allocation)
With help of Yuka, we think that https://github.com/root-project/root/commit/4653997fff48ea41a5fba1af7f4caa40bef1bc05 might be causing this. Root v6-14-00-patches branch without this fix ( i.e. https://github.com/cms-sw/root/commits/cms/v6-14-00-patches/0f67104 ) works fine.
Root v6-16-00-patches branch also works as [TCling][
ROOT-9660 is not in v6-16 branch.