------- Comment #4 from burnus at gcc dot gnu dot org 2010-07-13 12:04 ------- Thus: The derived type needs to be BIND(C) - but then it cannot be extended (as it is not extensible) - nor can the extended type be BIND(C) (per C1503). And without BIND(C) it is not interoperable - besides that polymorphic types are ruled out explicitly.
F2008 FDIS: "4.5.7.1 Concepts A derived type that does not have the BIND attribute or the SEQUENCE attribute is an extensible type." "15.2.3.6 C_LOC (X) [...] X shall have either the POINTER or TARGET attribute. It shall not be a coindexed object. It shall either be a variable with interoperable type and kind type parameters, or be a scalar, nonpolymorphic variable with no length type parameters. [...]" "15.3.4 Interoperability of derived types and C struct types A Fortran derived type is interoperable if it has the BIND attribute. C1501 (R425) A derived type with the BIND attribute shall not have the SEQUENCE attribute. C1502 (R425) A derived type with the BIND attribute shall not have type parameters. C1503 (R425) A derived type with the BIND attribute shall not have the EXTENDS attribute. C1504 (R425) A derived type with the BIND attribute shall not have a type-bound-procedure-part. C1505 (R425) Each component of a derived type with the BIND attribute shall be a nonpointer, nonallocatable data component with interoperable type and type parameters." -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44925
