Bug#823145: Qt4-using packages fail to build with gcc6

[Rene Engelhard <rene@debian.org>]

On Sun, May 08, 2016 at 01:05:47PM +0200, Rene Engelhard wrote:
> > By the way, is there any particular reason why LibreOffice buildsystem uses
> > -isystem /usr/include?
> 
> Probably some bug where it just adds whatever -I it finds (and be it
> /usr/include, which shouldn't be specificied but..) and then turns that into
> a -isystem...

>From configure:

checking for Qt4 headers... /usr/include/qt4
checking for qmake-qt4... /usr/bin/qmake-qt4
checking for Qt4 libraries... /usr/lib/aarch64-linux-gnu
checking for moc-qt4... /usr/bin/moc-qt4
checking for KDE4 headers... /usr/include
checking for KDE4 libraries... /usr/lib
checking for QT4... yes
checking whether KDE is >= 4.2... yes
checking for KDE_GLIB... yes
checking whether Qt has fixed ExcludeSocketNotifiers... no
configure: WARNING: native KDE4 file pickers will be disabled at runtime
tput: No value for $TERM and no -T specified
./configure: line 5038: test: -ge: unary operator expected
checking whether Qt avoids QClipboard recursion caused by posted events... no
configure: WARNING: native KDE4 file pickers will be disabled at runtime

Jup. See "checking for KDE4 headers... /usr/include". Which ends up as

export KDE4_CFLAGS=$(gb_SPACE)-isystem /usr/include -DQT_SHARED -isystem /usr/include/qt4 -isystem /usr/include/qt4/QtNetwork -isystem /usr/include/qt4 -isystem /usr/include/qt4/QtGui -isystem /usr/include/qt4 -isystem /usr/include/qt4/QtCore -DQT_CLEAN_NAMESPACE -DQT_THREAD_SUPPORT

Regards,
 
Rene