TStreamerInfo.cxx:1110:29: warning: ‘this’ pointer is null

[utkarsh-2000]

Hi all,
I was trying to build root from the source and then suddenly saw this warning. Can someone please explain its effects and resolution?

_ROOT Version:6.24.04
_Platform: Ubuntu 22.04
_Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0

---

 1110 |                      Warning("BuildCheck", "\n\
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~
 1111 |    The StreamerInfo from %s does not match existing one (%s:%d)\n\
      |    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 1112 |    The existing one has not been used yet and will be discarded.\n\
      |    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 1113 |    Reading should work properly, however writing object of\n\
      |    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 1114 |    type %s will not work properly.  Most likely the version number\n\
      |    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 1115 |    of the class was not properly updated [See ClassDef(%s,%d)].",
      |    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 1116 |                              file->GetName(), GetName(), fClassVersion, GetName(), GetName(), fClassVersion);
      |                              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Thanks a lot !

[moneta]

Are you trying to build a ROOT version downloaded from the ROOT Web site? When are you seeing the warning? For which class ?
@pcanal might be able to help you more on this

Lorenzo

[utkarsh-2000]

Thanks Lorenzo,
I installed the latest stable release using git clone hopefully it will work fine.
Yes, I was trying to build the source file downloaded from ROOT release.

I am not sure, as I have not saved the verbose, but I think it was ROOTIO or something related to input-output.