Как установить qBittorrent из tarball?

Источник Тарбол. Я начал с инструкций, найденных в файле «INSTALL», найденном в извлеченном tarball, и после того, как я набрал ./configure, после чего получил ошибку:

Configuring qbittorrent ...
Verifying Qt 4 build environment ... fail

Reason: There was an error compiling 'conf'.  See conf.log for details.

Be sure you have a proper Qt 4.0 build environment set up.  This means not
just Qt, but also a C++ compiler, a make tool, and any other packages
necessary for compiling C++ programs.

If you are certain everything is installed, then it could be that Qt 4 is not
being recognized or that a different version of Qt is being detected by
mistake (for example, this could happen if $QTDIR is pointing to a Qt 3
installation).  At least one of the following conditions must be satisfied:

 1) --qtdir is set to the location of Qt
 2) $QTDIR is set to the location of Qt
 3) QtCore is in the pkg-config database
 4) qmake is in the $PATH

This script will use the first one it finds to be true, checked in the above
order.  #3 and #4 are the recommended options.  #1 and #2 are mainly for
overriding the system configuration.