OTB 6.6-rc1 fails to build with GCC 8

Description

OTB 6.6-rc1 has been built with GCC 8 to test if Debian Bug #897830 was resolved now that ITK4 no longer fails to build with GCC 8.

Unfortunately OTB still fails to build:

In file included from /build/otb-6.6.0~rc1+dfsg/Modules/Adapters/GdalAdapters/include/otbGeometriesSet.h:27,
                 from /build/otb-6.6.0~rc1+dfsg/Modules/Adapters/GdalAdapters/src/otbGeometriesSet.cxx:25:
/build/otb-6.6.0~rc1+dfsg/Modules/Adapters/GdalAdapters/include/otbImageReference.h: In member function 'void otb::ogr::ImageReference<TPrecision>::TransformPointToPhysicalPoint(const PointType&) const':
/build/otb-6.6.0~rc1+dfsg/Modules/Adapters/GdalAdapters/include/otbImageReference.h:147:12: error: return-statement with a value, in function returning 'void' [-fpermissive]
     return physicalPoint;
            ^~~~~~~~~~~~~

Steps to reproduce

Build OTB with the gcc-8 & g++-8 packages from Debian unstable.

export CC=gcc-8
export CXX=g++-8

Configuration information

Debian unstable, OTB 6.6-rc1.