If you update a build of R-devel or R-patched from an SVN checkout you will need to ensure that 'methods' is rebuilt (rm -r library/methods/R suffices) once you see today's updates to src/library/base/R/formals.R. The reason is the long-standing infelicity that when you create an S4 generic for a function, it _copies_ the existing function as the default method rather than create a call to the existing function. This happens for body<- in the methods package itself, which in a vanilla session will mask the bug-fixed version in base. 'make check' will fail in R-devel but not in R-patched if 'methods' is not rebuilt. A clean build, including one from a tarball, will not have the problem.
Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595