I’ve just stumbled upon a strange behaviour in ROOT 6.20. If I create a simple C function in a file, for example this:
spec_test.C (113 Bytes)
Then in ROOT shell do
- .L spec_func.C++
- exit root
- run root again
On ROOT 6.20 I am getting
root  test_fun() /home/lewhoo/opt/root-6.20.00/bin/root.exe: symbol lookup error: /home/lewhoo/workspace/root_problems/spec_test_C.so: undefined symbol: _ZN6TGraphC1Ev
If I do the same on ROOT 6.18 everything seems to be fine:
root  test_fun() (TGraph *) 0x2d28dd0
This is not a TGraph issue, as I discovered it first with TSpectrum in a completely different function, called from python.
The same problem occurs at the current master. I am running Fedora 31.