[PATCH 3/4] Fix some aspects of python lazy string handling: scheme addition

[Doug Evans <dje at google dot com>]

Hi. This is a simple internal addition to the scheme support.

I separated it out for myself, as it helped to keep the python and scheme
sides comparable.

2016-11-06  Doug Evans  <dje@google.com>

	* guile/guile-internal.h (tyscm_scm_to_type): Declare.
	* guile/scm-type.c (tyscm_scm_to_type): New function.

diff --git a/gdb/guile/guile-internal.h b/gdb/guile/guile-internal.h
index 5f819b8..3597706 100644
--- a/gdb/guile/guile-internal.h
+++ b/gdb/guile/guile-internal.h
@@ -561,6 +561,8 @@ extern SCM tyscm_scm_from_type (struct type *type);
 extern type_smob *tyscm_get_type_smob_arg_unsafe (SCM type_scm, int  
arg_pos,
 						  const char *func_name);

+extern struct type *tyscm_scm_to_type (SCM t_scm);
+
 extern struct type *tyscm_type_smob_type (type_smob *t_smob);

 extern SCM tyscm_scm_from_field (SCM type_scm, int field_num);
diff --git a/gdb/guile/scm-type.c b/gdb/guile/scm-type.c
index 2acdfad..35d6588 100644
--- a/gdb/guile/scm-type.c
+++ b/gdb/guile/scm-type.c
@@ -347,6 +347,19 @@ tyscm_get_type_smob_arg_unsafe (SCM self, int arg_pos,  
const char *func_name)
   return t_smob;
 }

+/* Return the type field of T_SCM, an object of type <gdb:type>.
+   This exists so that we don't have to export the struct's contents.  */
+
+struct type *
+tyscm_scm_to_type (SCM t_scm)
+{
+  type_smob *t_smob;
+
+  gdb_assert (tyscm_is_type (t_scm));
+  t_smob = (type_smob *) SCM_SMOB_DATA (t_scm);
+  return t_smob->type;
+}
+
 /* Helper function for save_objfile_types to make a deep copy of the  
type.  */

 static int