[Bug c/96540] gcc fails to build on Darwin 19.6.0

[juergen.reuter at desy dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96540

--- Comment #2 from Jürgen Reuter <juergen.reuter at desy dot de> ---
Most likely this was that commit:
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 150)   template
<unsigned X> friend void gt_ggc_mx (int_range<X> *);
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 151)   template
<unsigned X> friend void gt_pch_nx (int_range<X> *);
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 152)   template
<unsigned X> friend void gt_pch_nx (int_range<X> *,
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 153)                 
                       gt_pointer_operator, void *);
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 154)   // ??
hash-traits.h has its own extern for these, which is causing
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 155)   // them to
never be picked up by the templates.  For now, define
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 156)   // elsewhere.
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 157)  
//template<unsigned X> friend void gt_ggc_mx (int_range<X> *&);
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 158)  
//template<unsigned X> friend void gt_pch_nx (int_range<X> *&);
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 159)   friend void
gt_ggc_mx (int_range<1> *&);
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 160)   friend void
gt_pch_nx (int_range<1> *&);
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 161) 
4ba9fb0a3e65 (Aldy Hernandez    2020-07-30 11:30:18 +0200 162)   tree
m_ranges[N*2];