Eliminate remaining gdb/guile cleanups

The remaining gdb/guile cleanups all handle the memory returned by
gdbscm_scm_to_c_string.

This commit makes gdbscm_scm_to_c_string return a
gdb::unique_xmalloc_ptr instead of a naked pointer, and eliminates the
remaining cleanups.

gdb/ChangeLog:
2018-07-19  Pedro Alves  <palves@redhat.com>

	* guile/guile-internal.h (gdbscm_scm_to_c_string): Now returns a
	gdb::unique_xmalloc_ptr.
	* guile/scm-breakpoint.c (gdbscm_set_breakpoint_condition_x):
	Adjust to use dbscm_wrap and gdb::unique_xmalloc_ptr.
	* guile/scm-exception.c (gdbscm_exception_message_to_string): Use
	copy-initialization.
	* guile/scm-pretty-print.c (ppscm_print_children): Use
	gdb::unique_xmalloc_ptr instead of cleanups.
	(gdbscm_apply_val_pretty_printer): Remove cleanups.
	* guile/scm-string.c (gdbscm_scm_to_c_string): Now returns a
	gdb::unique_xmalloc_ptr.
	* guile/scm-type.c (gdbscm_type_field, gdbscm_type_has_field_p):
	Adjust to use gdb::unique_xmalloc_ptr.
	* guile/scm-utils.c (extract_arg): Adjust.
	* guile/scm-value.c (gdbscm_value_field): Adjust to use
	gdb::unique_xmalloc_ptr instead of a cleanup.

1 files changed, 3 insertions, 9 deletions

diff --git a/gdb/guile/scm-value.c b/gdb/guile/scm-value.c
index 8d42d93..43f8001 100644
--- a/gdb/guile/scm-value.c
+++ b/gdb/guile/scm-value.c
@@ -619,20 +619,14 @@ gdbscm_value_field (SCM self, SCM field_scm)
     {
       scoped_value_mark free_values;
 
-      char *field = gdbscm_scm_to_c_string (field_scm);
-
-      struct cleanup *cleanups = make_cleanup (xfree, field);
+      gdb::unique_xmalloc_ptr<char> field = gdbscm_scm_to_c_string (field_scm);
 
       struct value *tmp = v_smob->value;
 
-      struct value *res_val = value_struct_elt (&tmp, NULL, field, NULL,
+      struct value *res_val = value_struct_elt (&tmp, NULL, field.get (), NULL,
 						"struct/class/union");
 
-      SCM result = vlscm_scm_from_value (res_val);
-
-      do_cleanups (cleanups);
-
-      return result;
+      return vlscm_scm_from_value (res_val);
     });
 }