Fix memory corruption in Guile command interface

Re-registering a command will delete previous commands of the same name,
running the destroyer for the command object.  The Guile destroyer
incorrectly tried to xfree the name and other strings, which is invalid
as they are on the GC heap.

gdb/ChangeLog:

	* guile/scm-cmd.c (cmdscm_destroyer): Don't xfree the name and
	other strings, as these are on the GC'd heap, and will be
	collected along with the smob.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 38d3005..4066a79 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,11 @@
 2015-03-11  Andy Wingo  <wingo@igalia.com>
 
+       * guile/scm-cmd.c (cmdscm_destroyer): Don't xfree the name and
+       other strings, as these are on the GC'd heap, and will be
+       collected along with the smob.
+
+2015-03-11  Andy Wingo  <wingo@igalia.com>
+
        * guile/scm-objfile.c (gdbscm_objfile_progspace): New function.
        (objfile_functions): Bind gdbscm_objfile_progspace to
        objfile-progspace.

diff --git a/gdb/guile/scm-cmd.c b/gdb/guile/scm-cmd.c
index c870fcc..202721b 100644 (file)
--- a/gdb/guile/scm-cmd.c
+++ b/gdb/guile/scm-cmd.c
@@ -286,11 +286,6 @@ cmdscm_destroyer (struct cmd_list_element *self, void *context)
   command_smob *c_smob = (command_smob *) context;
 
   cmdscm_release_command (c_smob);
-
-  /* We allocated the name, doc string, and perhaps the prefix name.  */
-  xfree ((char *) self->name);
-  xfree ((char *) self->doc);
-  xfree ((char *) self->prefixname);
 }
 
 /* Called by gdb to invoke the command.  */