I see this in warning spew during builds. The compiler is throwing up warning D9025 because we are passing both -GR- and -GR on the same command line. The latter is overriding the former.
That's done on purpose, because ICU *does* need RTTI.
Fair enough. Any chance we could get rid of the -GR- so that it doesn't raise a false alarm? Obviously to the untrained eye it looks like a build system bug, even thought that was intentional.
Not without large changes to the python code driving moz.build.