[Bug c++/79420] [7 Regression] ICE on invalid C++ code on x86_64-linux-gnu: in tsubst_copy, at cp/pt.c:14573

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79420

--- Comment #4 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
A similar testcase:

struct S;
extern S s;
template<int> int f ()
{ 
  return s.x;
}

void g ()
{ 
  f<0> ();
}