When you use BuildRoot the directory isn't created and the process stop with an error. It breaks spec files that worked perfectly in previous versions. Version in question is rpm-3.0.3-0.32.i386.rpm
Seems like bug#4097 is related qua error message. Only on this system "/var/tmp" is not a symbolic link but on a different filesystem.
I do not know why you think #4097 is related to your problem. What directory is not created? $RPM_BUILD_ROOT? It has *always* been the responsibility of the packager to create that directory, usually with some variant of ... %install rm -rf $RPM_BUILD_ROOT mkdir -p $RPM_BUILD_ROOT/usr/whatever ... %clean rm -rf $RPM_BUILD_ROOT