[Bug c/70297] [5 Regression] GCC Segfaults when using -g3

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70297

--- Comment #12 from Richard Biener <rguenth at gcc dot gnu.org> ---
On the branch also needs

2015-11-11  Jason Merrill  <jason@redhat.com>

        * decl.c (duplicate_decls): When combining typedefs, remove the
        new type from the variants list.