5.2.0 build fails on big endian archs

[krop]

The assimp 5.2.0 build fails on both ppc64 (be) and s390x:

[  794s] [ 24%] Building CXX object code/CMakeFiles/assimp.dir/AssetLib/IQM/IQMImporter.cpp.o
[  794s] cd /home/abuild/rpmbuild/BUILD/assimp-5.2.0/build/code && /usr/bin/c++ -DASSIMP_BUILD_DLL_EXPORT -DASSIMP_BUILD_NO_C4D_IMPORTER -DASSIMP_BUILD_NO_M3D_EXPORTER -DASSIMP_BUILD_NO_M3D_IMPORTER -DASSIMP_BUILD_NO_OWN_ZLIB -DASSIMP_IMPORTER_GLTF_USE_OPEN3DGC=1 -DMINIZ_USE_UNALIGNED_LOADS_AND_STORES=0 -DOPENDDLPARSER_BUILD -DRAPIDJSON_HAS_STDSTRING=1 -DRAPIDJSON_NOMEMBERITERATORCLASS -Dassimp_EXPORTS -I/home/abuild/rpmbuild/BUILD/assimp-5.2.0/build/include -I/home/abuild/rpmbuild/BUILD/assimp-5.2.0/build -I/home/abuild/rpmbuild/BUILD/assimp-5.2.0/include -I/home/abuild/rpmbuild/BUILD/assimp-5.2.0/code -I/home/abuild/rpmbuild/BUILD/assimp-5.2.0/. -I/home/abuild/rpmbuild/BUILD/assimp-5.2.0/code/../contrib/pugixml/src -I/home/abuild/rpmbuild/BUILD/assimp-5.2.0/code/../contrib/rapidjson/include -I/home/abuild/rpmbuild/BUILD/assimp-5.2.0/code/../contrib -I/home/abuild/rpmbuild/BUILD/assimp-5.2.0/code/../contrib/openddlparser/include -I/home/abuild/rpmbuild/BUILD/assimp-5.2.0/code/../include -I/home/abuild/rpmbuild/BUILD/assimp-5.2.0/build/code/../include -I/usr/include/minizip -fvisibility=hidden -fno-strict-aliasing -Wall -O2 -g -m64 -fmessage-length=0 -D_FORTIFY_SOURCE=2 -fstack-protector -funwind-tables -fasynchronous-unwind-tables -DNDEBUG -O2 -g -DNDEBUG -fPIC -Werror -std=gnu++11 -MD -MT code/CMakeFiles/assimp.dir/AssetLib/IQM/IQMImporter.cpp.o -MF CMakeFiles/assimp.dir/AssetLib/IQM/IQMImporter.cpp.o.d -o CMakeFiles/assimp.dir/AssetLib/IQM/IQMImporter.cpp.o -c /home/abuild/rpmbuild/BUILD/assimp-5.2.0/code/AssetLib/IQM/IQMImporter.cpp
[  794s] In file included from /home/abuild/rpmbuild/BUILD/assimp-5.2.0/code/AssetLib/IQM/IQMImporter.cpp:51:
[  794s] /home/abuild/rpmbuild/BUILD/assimp-5.2.0/code/AssetLib/IQM/IQMImporter.cpp: In function 'void swap_block(uint32_t*, size_t)':
[  794s] /home/abuild/rpmbuild/BUILD/assimp-5.2.0/code/AssetLib/IQM/IQMImporter.cpp:67:9: error: 'ByteSwap' has not been declared
[  794s]    67 |         AI_SWAP4( block[ i ] );
[  794s]       |         ^~~~~~~~
[  794s] make[2]: *** [code/CMakeFiles/assimp.dir/build.make:1297: code/CMakeFiles/assimp.dir/AssetLib/IQM/IQMImporter.cpp.o] Error 1

[umlaeute]

i was just going to report this :-)

isn't the proper fix to use fully qualified namespaces in the AI_SWAP4 macro?

that is, rather than

assimp/include/assimp/ByteSwapper.h

Line 223 in a214b08

# define AI_SWAP4(p) ByteSwap::Swap4(&(p))

it should read

#   define AI_SWAP4(p) Assimp::ByteSwap::Swap4(&(p)) 

(same for the other macros of coruse)