[Development] Qt5.8/Linux : -version `Qt_5' not found error running lrelease building qttranslations

[Thiago Macieira]

On quarta-feira, 18 de janeiro de 2017 18:46:53 PST René J. V. Bertin wrote:
> Thiago Macieira wrote:
> > Can you confirm whether the problem is
> > 
> >  a) that _ZN9QtPrivate16QStringList_joinERK11QStringList13QLatin1String
> >  isn't> 
> > present in QtCore at all; or
> 
> The symbol is present in the 5.8.0 version in the build tree, but not in the
> installed version.

I see that the QStringList::join(QLatin1String) overload was added in 5.8. 
Does t mean that the installed version is 5.7 or earlier?

> NB: it's only lrelease that fails, all other build steps complete just fine.
> I presume other executables must be called that also require new
> ABIs/symbols from QtCore . Setting LD_LIBRARY_PATH and QT_PLUGIN_PATH by
> hand I can also run just about any existing binary against Qt 5.8 .

So what's different with lrelease? Did the wrapper not set the correct 
LD_LIBRARY_PATH?

> >> %> ldd /path/to/build/qttools/bin/lrelease
> >> 
> >>         linux-vdso.so.1 =>  (0x00007ffdae338000)
> >>         libQt5Xml.so.5 => /opt/local/libexec/qt5/lib/libQt5Xml.so.5
> >>         (0x00007f148dac3000) libQt5Core.so.5 =>
> >>         /opt/local/libexec/qt5/lib/libQt5Core.so.5 (0x00007f148d3dc000)
> > 
> > Was that the correct QtCore?
> 
> That's the installed library, not the one it should be using as long as
> 5.8.0 has not been installed.

Ok, so that is the problem. The question is why LD_LIBRARY_PATH was not 
properly set. Or...

You mentioned:
> I have configured using -rpath

Check the lrelease binary with objdump -p: do you set RPATH? Do you see 
RUNPATH?

If you see the former but not the latter, then LD_LIBRARY_PATH has no effect. 
That would also explain this behaviour:

> Something is different between lrelease and other executables: ldd's output
> doesn't change for it when I set LD_LIBRARY_PATH as it does for qtdiag, for
> instance. Both result from the same build:

-- 
Thiago Macieira - thiago.macieira (AT) intel.com
  Software Architect - Intel Open Source Technology Center