FindOpenSceneGraph.cmake fails to get the version from OpenSceneGraph 3.6

[dmbaturin]

I'm trying to build using OpenSceneGraph branch 3.6 that I built from their git repository, and the CMake module fails in the following way:

[ FindOpenSceneGraph.cmake:157 ] Failed to parse version number, please report this as a bug
-- Found osgDB: /home/dmbaturin/opt/openmw/osg-openmw/lib/libosgDB.so  
-- Found osgViewer: /home/dmbaturin/opt/openmw/osg-openmw/lib/libosgViewer.so  
-- Found osgText: /home/dmbaturin/opt/openmw/osg-openmw/lib/libosgText.so  
-- Found osgGA: /home/dmbaturin/opt/openmw/osg-openmw/lib/libosgGA.so  
-- Found osgParticle: /home/dmbaturin/opt/openmw/osg-openmw/lib/libosgParticle.so  
-- Found osgUtil: /home/dmbaturin/opt/openmw/osg-openmw/lib/libosgUtil.so  
-- Found osgFX: /home/dmbaturin/opt/openmw/osg-openmw/lib/libosgFX.so  
-- Found osgShadow: /home/dmbaturin/opt/openmw/osg-openmw/lib/libosgShadow.so  
-- Found osgAnimation: /home/dmbaturin/opt/openmw/osg-openmw/lib/libosgAnimation.so  
-- Found osg: /home/dmbaturin/opt/openmw/osg-openmw/lib/libosg.so  
-- Found OpenThreads: /home/dmbaturin/opt/openmw/osg-openmw/lib/libOpenThreads.so  
CMake Error at /usr/share/cmake/Modules/FindOpenSceneGraph.cmake:226 (message):
  ERROR: Version 3.3.4 or higher of the OSG is required.  Version ..  was
  found.
Call Stack (most recent call first):
  CMakeLists.txt:358 (find_package)

I'm ready to do any additional testing if required.

The include/osg/Version file looks fine.

#ifndef OSG_VERSION
#define OSG_VERSION 1

#include <osg/Export>

extern "C" {

#define OPENSCENEGRAPH_MAJOR_VERSION    3
#define OPENSCENEGRAPH_MINOR_VERSION    6
#define OPENSCENEGRAPH_PATCH_VERSION    5
#define OPENSCENEGRAPH_SOVERSION        162

[dmbaturin]

Sorry, I forgot. My CMake version is 3.19.7