https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94973
--- Comment #16 from DB <db0451 at gmail dot com> --- > -fno-ms-extensions will allow you to compile it, as long as you aren't > relying on any of the other MSVC compatibility quirks. That indeed fixes the problem, as well as squashing lots of other spurious warnings (some of which default to errors!) from libsigc++ in the same project that were Windows-specific. Thanks!
