https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80766
--- Comment #5 from janus at gcc dot gnu.org ---
I have investigated a bit on the origin of the problem, and it seems that it is
related to the vtype symbols not being resolved properly (and the TBP component
having the type BT_UNKNOWN although it's a REAL function).
This rather simple patch fixes the ICE on trunk:
Index: gcc/fortran/resolve.c
===================================================================
--- gcc/fortran/resolve.c (revision 247818)
+++ gcc/fortran/resolve.c (working copy)
@@ -13833,6 +13833,9 @@ resolve_fl_derived (gfc_symbol *sym)
gcc_assert (vtab);
vptr->ts.u.derived = vtab->ts.u.derived;
}
+
+ if (!resolve_fl_derived0 (vptr->ts.u.derived))
+ return false;
}
if (!resolve_fl_derived0 (sym))
