These commits removed the 'NEEDED*' vars which were added so that CXX*
and LDFLAGS could be specified at build time. By doing away with these
and using solely CXXFLAGS and LDFLAGS, special flags cannot be added.
Indeed, specifying your own CXXFLAGS would cause the build to fail. We
want the build flags to be APPENDED, not overwritten.
Move old LDFLAGS variable to LDLIBS. By doing ths, a user can set their
own LDFLAGS without breaking the build. A case in which this can be
useful is hardening with debian, e.g.
$ dpkg-buildflags --get LDFLAGS
-Wl,-z,relro
