Python bindings work only with sources present.

[vvolkl]

When building LCIO and removing the sources, all python imports fail with many error messages of the type:

Error in <TClass::LoadClassInfo>: no interpreter information for class IMPL::TrackImpl is available even though it has a TClass initialization routine.
IMPL dictionary payload:5:10: fatal error: 'include/IMPL/AccessChecked.h' file not found
#include "include/IMPL/AccessChecked.h"

This is a bit reminiscent of AIDASoft/DD4hep#565. @andresailer, maybe your fix works here as well?

[andresailer]

The fix there was to have all the files available.

[rete]

@andresailer @vvolkl Is this fixed by now?

[tmadlener]

Potentially related: #136

[tmadlener]

This still seems to be an issue if one actually tries to use the python bindings

from pyLCIO import IOIMPL

reader = IOIMPL.LCFactory.getInstance().createLCReader()

fails with the following error

In file included from IOIMPL dictionary payload:9:
/cvmfs/sw.hsf.org/spackages/linux-centos7-x86_64/gcc-8.3.0/lcio-2.16.1-nqt55lk5fmwwer334skcjgjcihnbghmr/include/IOIMPL/LCEventLazyImpl.h:6:10: fatal error: 'SIO/SIOHandlerMgr.h' file not found
#include "SIO/SIOHandlerMgr.h"
         ^~~~~~~~~~~~~~~~~~~~~
Error in <TInterpreter::AutoParse>: Error parsing payload code for class IOIMPL::LCFactory with content:

[...]

This only seems to happen with out of source installations (i.e. spack). Installations with iLCSoft do not have this problem, although the <install-prefix>/include/SIO directory is empty in both cases.

[tmadlener]

I have checked that this also happens without spack and it does (if the sources from which LCIO is built are (re)moved). The two headers: SIOHandlerMgr.h and SIOObjectHandler.h need to be present in <install-prefix>/include/SIO for the above example to work.

Should we try and fix these installation issues in LCIO rather than in the spack recipe for LCIO?