Bug#1122881: qt6-base-dev: Installed mkspecs/ must not include qt_lib_*_private.pri files

[Johannes Kauffmann <johanneskauffmann@hotmail.com>]

Package: qt6-base-dev
Version: 6.4.2+dfsg-21.1build5
Severity: normal
X-Debbugs-Cc: johanneskauffmann@hotmail.com

Dear Maintainer,

The qt6-base-dev package includes, for all Qt modules shipped by qt6-base-dev:
1. qt_lib_${module}.pri files
2. qt_lib_${module}_private.pri files
They reside in the mkspecs/modules/ folder.

Because the qt_lib_${module}_private.pri files are packaged by qt6-base-dev instead of
qt6-base-private-dev, QMake's qtHaveModule() function thinks that private headers are installed,
even when qt6-base-private-dev is not installed. As such the following appears to work:

  qtHaveModule(gui-private) {
      QT += gui-private
      DEFINES += HAVE_GUI_PRIVATE
  }

... but it breaks because the header just isn't there but QMake thinks it is:

  #if defined HAVE_GUI_PRIVATE
  # include <QtGui/qpa/qplatformwindow.h>
  #endif

Moving the mkspecs/modules/qt_lib_${module}_private.pri files to qt6-base-private-dev should be
enough to fix the issue.

For reference, this is resulting from: https://code.videolan.org/videolan/vlc/-/issues/29409

Kind regards,
Johannes Kauffmann

-- System Information:
Debian Release: trixie/sid
  APT prefers noble-updates
  APT policy: (500, 'noble-updates'), (500, 'noble-security'), (500, 'noble-proposed'), (500, 'noble'), (100, 'noble-backports')
Architecture: amd64 (x86_64)

Kernel: Linux 6.6.87.2-microsoft-standard-WSL2 (SMP w/8 CPU threads; PREEMPT)
Locale: LANG=C.UTF-8, LC_CTYPE=C.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages qt6-base-dev depends on:
ii  libgl-dev                1.7.0-1build1
ii  libglx-dev               1.7.0-1build1
ii  libopengl-dev            1.7.0-1build1
ii  libqt6concurrent6t64     6.4.2+dfsg-21.1build5
ii  libqt6core6t64           6.4.2+dfsg-21.1build5
ii  libqt6dbus6t64           6.4.2+dfsg-21.1build5
ii  libqt6gui6t64            6.4.2+dfsg-21.1build5
ii  libqt6network6t64        6.4.2+dfsg-21.1build5
ii  libqt6openglwidgets6t64  6.4.2+dfsg-21.1build5
ii  libqt6printsupport6t64   6.4.2+dfsg-21.1build5
ii  libqt6sql6t64            6.4.2+dfsg-21.1build5
ii  libqt6test6t64           6.4.2+dfsg-21.1build5
ii  libqt6widgets6t64        6.4.2+dfsg-21.1build5
ii  libqt6xml6t64            6.4.2+dfsg-21.1build5
ii  libvulkan-dev            1.3.275.0-1build1
ii  qmake6                   6.4.2+dfsg-21.1build5
ii  qt6-base-dev-tools       6.4.2+dfsg-21.1build5
ii  qt6-qpa-plugins          6.4.2+dfsg-21.1build5

qt6-base-dev recommends no packages.

qt6-base-dev suggests no packages.

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