re PR fortran/49630 ([OOP] ICE on obsolescent deferred-length type bound character function)

2018-06-21  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/49630
	* resolve.c (resolve_contained_fntype): Change standard ref.
	from F95 to F2003: C418. Correct a spelling error in a comment.
	It is an error for an abstract interface to have an assumed
	character length result.
	* trans-expr.c (gfc_conv_procedure_call): Likewise change the
	standard reference.

2018-06-21  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/49630
	* gfortran.dg/assumed_charlen_function_7.f90: New test.

From-SVN: r261868

1 files changed, 15 insertions, 3 deletions

diff --git a/gcc/fortran/resolve.c b/gcc/fortran/resolve.c
index 1cc3165..4104054 100644
--- a/gcc/fortran/resolve.c
+++ b/gcc/fortran/resolve.c
@@ -601,9 +601,10 @@ resolve_contained_fntype (gfc_symbol *sym, gfc_namespace *ns)
 	}
     }
 
-  /* Fortran 95 Draft Standard, page 51, Section 5.1.1.5, on the Character
+  /* Fortran 2003 Draft Standard, page 535, C418, on type-param-value
      type, lists the only ways a character length value of * can be used:
-     dummy arguments of procedures, named constants, and function results
+     dummy arguments of procedures, named constants, function results and
+     in allocate statements if the allocate_object is an assumed length dummy
      in external functions.  Internal function results and results of module
      procedures are not on this list, ergo, not permitted.  */
 
@@ -3103,7 +3104,7 @@ resolve_function (gfc_expr *expr)
       return false;
     }
 
-  /* If this ia a deferred TBP with an abstract interface (which may
+  /* If this is a deferred TBP with an abstract interface (which may
      of course be referenced), expr->value.function.esym will be set.  */
   if (sym && sym->attr.abstract && !expr->value.function.esym)
     {
@@ -3112,6 +3113,17 @@ resolve_function (gfc_expr *expr)
       return false;
     }
 
+  /* If this is a deferred TBP with an abstract interface, its result
+     cannot be an assumed length character (F2003: C418).  */
+  if (sym && sym->attr.abstract && sym->attr.function
+      && sym->result->ts.u.cl->length == NULL)
+    {
+      gfc_error ("ABSTRACT INTERFACE %qs at %L must not have an assumed "
+		 "character length result (F2003: C418)", sym->name,
+		 &sym->declared_at);
+      return false;
+    }
+
   /* Switch off assumed size checking and do this again for certain kinds
      of procedure, once the procedure itself is resolved.  */
   need_full_assumed_size++;