does not allow access declarations - Rebuild of the Debian archive with clang

"does not allow access declarations" build failure(s)
clang 13.0.0

Versions: 2.9 - 3.0 - 3.1 - 3.2 - 3.3 - 3.4 - 3.4.2 - 3.5.0 - 3.6.0 - 3.8.1 - 3.9.1 - 4.0.1 - 5.0 - 6.0 - 8.0.1 - 9.0.1 - 10.0.0 - 11.0.0 - 12.0.1 - 13.0.0

Package	Version	Supposed error message	Full log
bigint	2010.04.30-2	:/<>/BigUnsigned.hh/<>/BigUnsigned.hh23:::232324:::2424 ::error: ISO C++11 does not allow access declarations; use using declarations insteaderror: error:	Log
opensp	1.5.2-13	../include/Ptr.h:72:11: error: ISO C++11 does not allow access declarations; use using declarations instead	Log
vdr-plugin-osdserver	0.1.3-20	./osdobjects.h:59:19: error: ISO C++11 does not allow access declarations; use using declarations instead	Log

3 errors

Debian Package rebuild