https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65072
--- Comment #7 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Here, we SEGV in build_class_member_access_expr, called recursively:
tree anonymous_union;
anonymous_union = lookup_anon_field (TREE_TYPE (object),
DECL_CONTEXT (member));
object = build_class_member_access_expr (object,
anonymous_union, [...]
anonymous_union is NULL and build_class_member_access_expr is not prepared to
handle that. anonymous_union is NULL because lookup_anon_field returned NULL:
it tried to look for a "struct ._0" type in "const struct C" -- and found
nothing. That is because "const struct C" doesn't have any fields! But if I
change the testcase so that C is not const, it passes, because "struct C" then
has fields and lookup_anon_field is able to find a FIELD_DECL.
So the question is why "const struct C" doesn't have any fields. I couldn't
figure that out yet :(.
