Problem with memory resident tree

Hallo everyone,

I have problem when I want to create a root file from another root file, it work but before finishing turning I see these comments in terminal (see below). Noting that I created my Tfile before TTree.

Finally, I create a root file but I’m afraid that I’m losing some data in this file.

Have you an idea about that, please?

Thank you very much in advance,

example:
Error in TTree::Fill: Failed filling branch:T.ft, nbytes=-1, entry=56428467
This error is symptomatic of a Tree created as a memory-resident Tree
Instead of doing:
TTree *T = new TTree(…)
TFile *f = new TFile(…)
you should do:
TFile *f = new TFile(…)
TTree *T = new TTree(…)
Error in TTree::Fill: Failed filling branch:T.ft_d, nbytes=-1, entry=56428467
This error is symptomatic of a Tree created as a memory-resident Tree
Instead of doing:
TTree *T = new TTree(…)
TFile *f = new TFile(…)
you should do:
TFile *f = new TFile(…)
TTree *T = new TTree(…)
Error in TTree::Fill: Failed filling branch:T.ft_n, nbytes=-1, entry=56428467
Error in TTree::Fill: Failed filling branch:T.phi, nbytes=-1, entry=56428467

Can you share the code you use to create the output TFile and the TTree?