qt6-graphs fails to cross build from source, because QT_HOST_PATH is not
passed. I'm attaching the obvious patch for your convenience.

Helmut

We believe that the bug you reported is fixed in the latest version of
qt6-graphs, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1113858@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Patrick Franz <deltaone@debian.org> (supplier of updated qt6-graphs package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Wed, 03 Sep 2025 18:25:10 +0200
Source: qt6-graphs
Architecture: source
Version: 6.9.1-4
Distribution: experimental
Urgency: medium
Maintainer: Debian Qt/KDE Maintainers <debian-qt-kde@lists.debian.org>
Changed-By: Patrick Franz <deltaone@debian.org>
Closes: 1113858
Changes:
 qt6-graphs (6.9.1-4) experimental; urgency=medium
 .
   [ Patrick Franz ]
   * Fix FTCBFS: Pass QT_HOST_PATH, thx to Helmut Grohne (Closes:
     #1113858).
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