Fix:
 * crashes on memory allocation failure found with failmalloc
 * memory leaks found with valgrind
 * compiler warnings in opt mode which would lead to invalid memory reads
 * problem using wrong name in decimal module reported by pychecker

Update the valgrind suppressions file with new leaks that are small/one-time
leaks we don't care about (ie, they are too hard to fix).

TBR=barry
TESTED=./python -E -tt ./Lib/test/regrtest.py -uall (both debug and opt modes)
  in opt mode:
  valgrind -q --leak-check=yes --suppressions=Misc/valgrind-python.supp \
    ./python -E -tt ./Lib/test/regrtest.py -uall,-bsddb,-compiler \
                        -x test_logging test_ssl test_multiprocessing
  valgrind -q --leak-check=yes --suppressions=Misc/valgrind-python.supp \
    ./python -E -tt ./Lib/test/regrtest.py test_multiprocessing
  for i in `seq 1 4000` ; do
    LD_PRELOAD=~/local/lib/libfailmalloc.so FAILMALLOC_INTERVAL=$i \
        ./python -c pass
  done

At least some of these fixes should probably be backported to 2.5.
diff --git a/Objects/stringlib/formatter.h b/Objects/stringlib/formatter.h
index b964435..aa99123 100644
--- a/Objects/stringlib/formatter.h
+++ b/Objects/stringlib/formatter.h
@@ -641,7 +641,10 @@
 	    /* We know this can't fail, since we've already
 	       reserved enough space. */
 	    STRINGLIB_CHAR *pstart = p + n_leading_chars;
-	    int r = STRINGLIB_GROUPING(pstart, n_digits, n_digits,
+#ifndef NDEBUG
+	    int r =
+#endif
+		STRINGLIB_GROUPING(pstart, n_digits, n_digits,
 			   spec.n_total+n_grouping_chars-n_leading_chars,
 			   NULL, 0);
 	    assert(r);
diff --git a/Objects/structseq.c b/Objects/structseq.c
index b6126ba..ad246a1 100644
--- a/Objects/structseq.c
+++ b/Objects/structseq.c
@@ -32,6 +32,8 @@
 	PyStructSequence *obj;
 
 	obj = PyObject_New(PyStructSequence, type);
+	if (obj == NULL)
+		return NULL;
 	Py_SIZE(obj) = VISIBLE_SIZE_TP(type);
 
 	return (PyObject*) obj;
@@ -522,10 +524,16 @@
 	Py_INCREF(type);
 
 	dict = type->tp_dict;
-	PyDict_SetItemString(dict, visible_length_key, 
-		       PyInt_FromLong((long) desc->n_in_sequence));
-	PyDict_SetItemString(dict, real_length_key, 
-		       PyInt_FromLong((long) n_members));
-	PyDict_SetItemString(dict, unnamed_fields_key, 
-		       PyInt_FromLong((long) n_unnamed_members));
+#define SET_DICT_FROM_INT(key, value)				\
+	do {							\
+		PyObject *v = PyInt_FromLong((long) value);	\
+		if (v != NULL) {				\
+			PyDict_SetItemString(dict, key, v);	\
+			Py_DECREF(v);				\
+		}						\
+	} while (0)
+
+	SET_DICT_FROM_INT(visible_length_key, desc->n_in_sequence);
+	SET_DICT_FROM_INT(real_length_key, n_members);
+	SET_DICT_FROM_INT(unnamed_fields_key, n_unnamed_members);
 }