"Project ERROR: Library 'assimp' is not defined" when building Qt 5.15.6

[Creaperdown]

Hey, when building Qt 5.15.5 I am getting this error:

cd assimp/ && ( test -e Makefile || /home/creapermann/Programming/qt-5.15.6/qtbase/bin/qmake -o Makefile /home/creapermann/Programming/qt-5.15.6/qtquick3d/src/plugins/assetimporters/assimp/assimp.pro ) && make -f Makefile install
Project ERROR: Library 'assimp' is not defined.
make[4]: *** [Makefile:85: sub-assimp-install_subtargets] Error 3
make[4]: Leaving directory '/home/creapermann/Programming/qt-5.15.6/qtquick3d/src/plugins/assetimporters'
make[3]: *** [Makefile:59: sub-assetimporters-install_subtargets] Error 2
make[3]: Leaving directory '/home/creapermann/Programming/qt-5.15.6/qtquick3d/src/plugins'
make[2]: *** [Makefile:206: sub-plugins-install_subtargets-ordered] Error 2
make[2]: Leaving directory '/home/creapermann/Programming/qt-5.15.6/qtquick3d/src'
make[1]: *** [Makefile:62: sub-src-install_subtargets] Error 2
make[1]: Leaving directory '/home/creapermann/Programming/qt-5.15.6/qtquick3d'
make: *** [Makefile:377: module-qtquick3d-install_subtargets] Error 2

Does anyone have an idea why?

[Paul Colby]

Hi @Creaperdown,

Looks like you might have run into QTBUG-84037?

My read of that bug report is that it happens when using some particular versions of libassimp. Seems it was fixed in a later versions of that library, but the workaround (if you can't get a more recent libassimp version) is to tweak the assimp.pro file. Have a read, and see if that makes sense / works for you.

Cheers.

[Creaperdown]

@Paul-Colby Thanks, this works!