[Patch, Fortran, F03] PR 40882: infinite recursion in gfc_get_derived_type with PPC returning derived type

[Janus Weil <janus at gcc dot gnu dot org>]

Hi all,

this is fixing a small problem with procedure pointer components
returning a derived type. If the result type is the same as the type
which contains the PPC, gfc_get_derived_type would enter an infinite
recursion loop. The patch handles this case in a similar fashion as
for pointer components, i.e. first making sure all the backend_decl's
of derived types are there, and then using those backend_decl's
instead of recursing to gfc_get_derived_type.

Regtested on x86_64-unknown-linux-gnu. Ok for trunk?

Cheers,
Janus


2009-07-28  Janus Weil  <janus@gcc.gnu.org>

	PR fortran/40882
	* trans-types.c (gfc_get_ppc_type): For derived types, directly use the
	backend_decl, instead of calling gfc_typenode_for_spec, to avoid
	infinte loop.
	(gfc_get_derived_type): Correctly handle PPCs returning derived types,
	avoiding infinite recursion.


2009-07-28  Janus Weil  <janus@gcc.gnu.org>

	PR fortran/40882
	* gfortran.dg/proc_ptr_comp_13.f90: New.

Index: gcc/fortran/trans-types.c
===================================================================
--- gcc/fortran/trans-types.c	(revision 150133)
+++ gcc/fortran/trans-types.c	(working copy)
@@ -1894,7 +1894,12 @@ gfc_get_ppc_type (gfc_component* c)
 {
   tree t;
   if (c->attr.function && !c->attr.dimension)
-    t = gfc_typenode_for_spec (&c->ts);
+    {
+      if (c->ts.type == BT_DERIVED)
+	t = c->ts.derived->backend_decl;
+      else
+	t = gfc_typenode_for_spec (&c->ts);
+    }
   else
     t = void_type_node;
   /* TODO: Build argument list.  */
@@ -1974,7 +1979,8 @@ gfc_get_derived_type (gfc_symbol * deriv
       if (c->ts.type != BT_DERIVED)
 	continue;
 
-      if (!c->attr.pointer || c->ts.derived->backend_decl == NULL)
+      if ((!c->attr.pointer && !c->attr.proc_pointer)
+	  || c->ts.derived->backend_decl == NULL)
 	c->ts.derived->backend_decl = gfc_get_derived_type (c->ts.derived);
 
       if (c->ts.derived && c->ts.derived->attr.is_iso_c)
@@ -2003,10 +2009,10 @@ gfc_get_derived_type (gfc_symbol * deriv
   fieldlist = NULL_TREE;
   for (c = derived->components; c; c = c->next)
     {
-      if (c->ts.type == BT_DERIVED)
-        field_type = c->ts.derived->backend_decl;
-      else if (c->attr.proc_pointer)
+      if (c->attr.proc_pointer)
 	field_type = gfc_get_ppc_type (c);
+      else if (c->ts.type == BT_DERIVED)
+        field_type = c->ts.derived->backend_decl;
       else
 	{
 	  if (c->ts.type == BT_CHARACTER)

Attachment: proc_ptr_comp_13.f90
Description: Binary data