Randomly a segmentation fault for uninitialized TTree

[Wile_E_Coyote]

Try with the AddressSanitizer, e.g.:

`root-config --cxx --cflags` -O0 -g -fno-omit-frame-pointer -fsanitize=address -Wall -Wextra -o a.out *.cpp -lasan `root-config --libs`
ASAN_OPTIONS="verbosity=1:abort_on_error=0" ./a.out