Navit FTBFS - cmake fix needed to work with newer pango

[Christian Ehrhardt ]

## Cmake ##

A change in Pango [1] broke builds using GTK2 as the pango source will include hb.h but miss the proper include paths.

A fix was brought up in [2] and should be added to cmake in Focal to allow things to build with the new pango.

Focal currently is at cmake 3.15.4-1 and [3] is a backport of that change to the 3.15 series.

Note: after that is resolved navit will need a no change rebuild to pick up libgpsd25 which got me initially to find this issue.

[1]: https://gitlab.gnome.org/GNOME/pango/commit/a7b17aa2bad77c485943c860a20aedc2b2b115ff
[2]: https://gitlab.kitware.com/cmake/cmake/issues/19531
[3]: https://gitlab.kitware.com/cmake/cmake/commit/e4b1b79abb2b6e1ad07d36d4734554972c9ce4a9

--- original report ---

## Navit ##

In file included from /usr/include/pango-1.0/pango/pango-font.h:25,
                 from /usr/include/pango-1.0/pango/pango-attributes.h:25,
                 from /usr/include/pango-1.0/pango/pango.h:25,
                 from /usr/include/gtk-2.0/gdk/gdktypes.h:37,
                 from /usr/include/gtk-2.0/gdk/gdkscreen.h:32,
                 from /usr/include/gtk-2.0/gdk/gdkapplaunchcontext.h:31,
                 from /usr/include/gtk-2.0/gdk/gdk.h:32,
                 from /usr/include/gtk-2.0/gtk/gtk.h:32,
                 from /<<BUILDDIR>>/navit-0.5.3+dfsg.1/navit/graphics/gtk_drawing_area/graphics_gtk_drawing_area.c:26:
/usr/include/pango-1.0/pango/pango-coverage.h:28:10: fatal error: hb.h: No such file or directory
   28 | #include <hb.h>
      | ^~~~~~
compilation terminated.

In file included from /usr/include/pango-1.0/pango/pango-font.h:25,
                 from /usr/include/pango-1.0/pango/pango-attributes.h:25,
                 from /usr/include/pango-1.0/pango/pango.h:25,
                 from /usr/include/gtk-2.0/gdk/gdktypes.h:37,
                 from /usr/include/gtk-2.0/gdk/gdkscreen.h:32,
                 from /usr/include/gtk-2.0/gdk/gdkapplaunchcontext.h:31,
                 from /usr/include/gtk-2.0/gdk/gdk.h:32,
                 from /usr/include/gtk-2.0/gtk/gtk.h:32,
                 from /<<BUILDDIR>>/navit-0.5.3+dfsg.1/navit/gui/gtk/datawindow.c:24:
/usr/include/pango-1.0/pango/pango-coverage.h:28:10: fatal error: hb.h: No such file or directory
   28 | #include <hb.h>
      | ^~~~~~
compilation terminated.

These are from no change rebuilds needed for libgps25, but something else made them break.

[Christian Ehrhardt  (paelzer)]

navit actually just naively includes <gtk/gtk.h> and the error pups up much below that.

It has #define GDK_ENABLE_BROKEN might that be related?

Build dep is:
  libgtk2.0-dev
Which brings in:
 libpango1.0-dev | 1.44.7-1 | focal | amd64, arm64, armhf, i386, ppc64el, s390x

And that has the failing include:
grep -Hn hb.h /usr/include/pango-1.0/pango/pango-coverage.h
/usr/include/pango-1.0/pango/pango-coverage.h:28:#include <hb.h>

The only occurrence of that is in:
$ apt-file search 'hb.h' | grep -e '/hb\.h$'
libharfbuzz-dev: /usr/include/harfbuzz/hb.h
thunderbird-dev: /usr/include/thunderbird/harfbuzz/hb.h

Odd, did it really want that one ...?

[Christian Ehrhardt  (paelzer)]

Added a pango1.0 task for awareness

[Christian Ehrhardt  (paelzer)]

navit last time built fine in Eoan on 2019-09-10

Comparing the environments between late Eoan and Focal...

The Eoan version of pango-coverage.h doesn't have the include that is failing me.

[Christian Ehrhardt  (paelzer)]

#ubuntu-desktop was helpful:

[11:29] <seb128> cpaelzer, hey, it's https://gitlab.kitware.com/cmake/cmake/issues/19531
[11:29] <seb128> RikMills, ^
[11:29] <seb128> cpaelzer, we talked about it on friday on #ubuntu-release, we should backport that patch to cmake

[Christian Ehrhardt  (paelzer)]

I'm preparing an interim fix for navit to get out of the way of this and less dependent on the cmake fix. We can revert that once cmake is up to date.

But sooner or later this should probably be fixed in cmake either with a backport or a move to the 3.16 version that has the change anyway.

[Launchpad Janitor (janitor)]

This bug was fixed in the package navit - 0.5.3+dfsg.1-2ubuntu1

---------------
navit (0.5.3+dfsg.1-2ubuntu1) focal; urgency=medium

  * d/rules: until resolved in cmake append the harfbuzz include directory
    directly to fix FTBFS (LP: #1855993)

 -- Christian Ehrhardt <email address hidden> Wed, 11 Dec 2019 12:03:05 +0100