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.

Objects/stringlib/formatter.h

@@ -641,7 +641,10 @@ format_int_or_long_internal(PyObject *value, const InternalFormatSpec *format,
 	    /* 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);