G++5 ABI + TMVA - which branch to compile?

First of all: I like bleeding edge versions :smiley:

According to sft.its.cern.ch/jira/browse/ROOT-7947 “The new llvm with GCC5 ABI support has arrived in the master” -> thus I thought I could try the new root version on an operating system with gcc5. Compiling git master seemed to work so far.

However, I ran into a problem with TMVA: the TMVA::Factory does not have AddVariable/AddTarget/AddSpectator functions any more, seems to work via a DataSet(?) - I couldn’t find any documentation on this. As this change is already in master for a longer time (introduced with commit f009d8e, Nov 2015) and there have been other releases like 6.06.* after that date that don’t contain these changes, I am asking which branch I need to compile.

master -> TMVA seems to use a new mechanism to add variables
v6-06-00-patches -> GCC ABI issues

So can I get both?
Q: is there updated documentation for the TMVA in master? Is the new interface stable and ready for use?
Q: is there some v6-* branch which contains an updated llvm but not the interface breaking TMVA updates?

Hi,

you can find the tutorials of TMVA here: root.cern.ch/doc/master/group__ … _tmva.html . You can certainly start from there to see the new, stable interface in action.
Since you like bleeding edge versions, you can try the one of yesterday: commit e7cec4 :slight_smile:
For what concerns release planning, we are preparing to release ROOT 6.08 in the next few weeks.

Cheers,
Danilo

PS
To complete your correct observations:
o The refactoring of TMVA entered the code base from 6.07 development releases onwards: 6.06 releases have the old interface.
o The new ABI support entered the release after the 6.06 release too.