[patch, fortran] Separate READ from WRITE

[Tobias Burnus]

  Thomas Koenig wrote:
> Well, feedback seems to have been positive, so here is the formal patch
> with a proper changelog entry.

No review yet but:

    iocall[IOCALL_X_LOGICAL] = gfc_build_library_function_decl_with_spec (
  	get_identifier (PREFIX("transfer_logical")), ".wW",
  	void_type_node, 3, dt_parm_type, pvoid_type_node, gfc_int4_type_node);

+  iocall[IOCALL_X_LOGICAL_WRITE] = gfc_build_library_function_decl_with_spec (
+	get_identifier (PREFIX("transfer_logical_write")), ".rW",
+	void_type_node, 3, dt_parm_type, pvoid_type_node, gfc_int4_type_node);
+


I think one also needs to update the "fn spec" for "transfer_logical" 
besides adding "transfer_logical_write". I am also a bit lost whether 
".rW" is correct - I always get confused which argument is for what and 
whether some status is also updated in dtp or whether it only contains 
the internal-I/O string and the format string. I had expected that the 
fn-spec should be ".wR" for WRITE, i.e. that the dtp might be written to 
(for internal I/O) but that the second argument is only read from (R). 
While for READ, I would expect the ".rW" which your patch has for 
transfer_logical_write (assuming that no status is returned via dtp 
during a transfer call).

Tobias