157 files changed, 862 insertions, 491 deletions
diff --git a/Demo/tkinter/guido/brownian2.py b/Demo/tkinter/guido/brownian2.py
new file mode 100644
index 0000000..281a645
--- /dev/null
+++ b/Demo/tkinter/guido/brownian2.py
@@ -0,0 +1,55 @@
+# Brownian motion -- an example of a NON multi-threaded Tkinter program ;)
+# By Michele Simoniato, inspired by brownian.py
+
+from Tkinter import *
+import random
+import sys
+
+WIDTH = 400
+HEIGHT = 300
+SIGMA = 10
+BUZZ = 2
+RADIUS = 2
+LAMBDA = 10
+FILL = 'red'
+
+stop = 0                                # Set when main loop exits
+root = None                             # main window
+
+def particle(canvas):                   # particle = iterator over the moves
+    r = RADIUS
+    x = random.gauss(WIDTH/2.0, SIGMA)
+    y = random.gauss(HEIGHT/2.0, SIGMA)
+    p = canvas.create_oval(x-r, y-r, x+r, y+r, fill=FILL)
+    while not stop:
+        dx = random.gauss(0, BUZZ)
+        dy = random.gauss(0, BUZZ)
+        try:
+            canvas.move(p, dx, dy)
+        except TclError:
+            break
+        else:
+            yield None
+
+def move(particle): # move the particle at random time
+    particle.next()
+    dt = random.expovariate(LAMBDA)
+    root.after(int(dt*1000), move, particle)
+
+def main():
+    global root, stop
+    root = Tk()
+    canvas = Canvas(root, width=WIDTH, height=HEIGHT)
+    canvas.pack(fill='both', expand=1)
+    np = 30
+    if sys.argv[1:]:
+        np = int(sys.argv[1])
+    for i in range(np):                  # start the dance
+        move(particle(canvas))
+    try:
+        root.mainloop()
+    finally:
+        stop = 1
+
+if __name__ == '__main__':
+    main()
diff --git a/Doc/library/os.rst b/Doc/library/os.rst
index a550739..0436244 100644
--- a/Doc/library/os.rst
+++ b/Doc/library/os.rst
@@ -597,14 +597,7 @@ platforms.  For descriptions of their availability and use, consult
 
 
 .. data:: O_BINARY
-
-   Option for the *flag* argument to the :func:`open` function. This can be
-   bit-wise OR'd together with those listed above. Availability: Windows.
-
-   .. % XXX need to check on the availability of this one.
-
-
-.. data:: O_NOINHERIT
+          O_NOINHERIT
           O_SHORT_LIVED
           O_TEMPORARY
           O_RANDOM
@@ -615,6 +608,15 @@ platforms.  For descriptions of their availability and use, consult
    bit-wise OR'd together. Availability: Windows.
 
 
+.. data:: O_DIRECT
+          O_DIRECTORY
+          O_NOFOLLOW
+          O_NOATIME
+
+   Options for the *flag* argument to the :func:`open` function. These are
+   GNU extensions and not present if they are not defined by the C library.
+
+
 .. data:: SEEK_SET
           SEEK_CUR
           SEEK_END
diff --git a/Doc/library/subprocess.rst b/Doc/library/subprocess.rst
index 5ac32df..d260473 100644
--- a/Doc/library/subprocess.rst
+++ b/Doc/library/subprocess.rst
@@ -189,7 +189,12 @@ Instances of the :class:`Popen` class have the following methods:
 
    communicate() returns a tuple (stdout, stderr).
 
-   .. note::
+   Note that if you want to send data to the process's stdin, you need to create
+   the Popen object with ``stdin=PIPE``.  Similarly, to get anything other than
+   ``None`` in the result tuple, you need to give ``stdout=PIPE`` and/or
+   ``stderr=PIPE`` too.
+
+.. note::
 
       The data read is buffered in memory, so do not use this method if the data size
       is large or unlimited.
diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst
index b1315c0..7703ad9 100644
--- a/Doc/library/unittest.rst
+++ b/Doc/library/unittest.rst
@@ -804,8 +804,9 @@ tools which support interactive reporting while tests are being run.
    Called when the test case *test* raises an unexpected exception *err* is a tuple
    of the form returned by :func:`sys.exc_info`: ``(type, value, traceback)``.
 
-   The default implementation appends ``(test, err)`` to the instance's ``errors``
-   attribute.
+   The default implementation appends a tuple ``(test, formatted_err)`` to the
+   instance's ``errors`` attribute, where *formatted_err* is a formatted
+   traceback derived from *err*.
 
 
 .. method:: TestResult.addFailure(test, err)
@@ -813,8 +814,9 @@ tools which support interactive reporting while tests are being run.
    Called when the test case *test* signals a failure. *err* is a tuple of the form
    returned by :func:`sys.exc_info`:  ``(type, value, traceback)``.
 
-   The default implementation appends ``(test, err)`` to the instance's
-   ``failures`` attribute.
+   The default implementation appends a tuple ``(test, formatted_err)`` to the
+   instance's ``failures`` attribute, where *formatted_err* is a formatted
+   traceback derived from *err*.
 
 
 .. method:: TestResult.addSuccess(test)
diff --git a/Doc/library/xml.dom.rst b/Doc/library/xml.dom.rst
index e13999c..d75db2c 100644
--- a/Doc/library/xml.dom.rst
+++ b/Doc/library/xml.dom.rst
@@ -29,11 +29,14 @@ representation for XML data.
 
 The Document Object Model is being defined by the W3C in stages, or "levels" in
 their terminology.  The Python mapping of the API is substantially based on the
-DOM Level 2 recommendation.  The mapping of the Level 3 specification, currently
-only available in draft form, is being developed by the `Python XML Special
-Interest Group <http://www.python.org/sigs/xml-sig/>`_ as part of the `PyXML
-package <http://pyxml.sourceforge.net/>`_.  Refer to the documentation bundled
-with that package for information on the current state of DOM Level 3 support.
+DOM Level 2 recommendation.
+
+.. XXX PyXML is dead...
+.. The mapping of the Level 3 specification, currently
+   only available in draft form, is being developed by the `Python XML Special
+   Interest Group <http://www.python.org/sigs/xml-sig/>`_ as part of the `PyXML
+   package <http://pyxml.sourceforge.net/>`_.  Refer to the documentation bundled
+   with that package for information on the current state of DOM Level 3 support.
 
 .. % What if your needs are somewhere between SAX and the DOM?  Perhaps
 .. % you cannot afford to load the entire tree in memory but you find the
@@ -74,10 +77,6 @@ implementations are free to support the strict mapping from IDL).  See section
    `Document Object Model (DOM) Level 1 Specification <http://www.w3.org/TR/REC-DOM-Level-1/>`_
       The W3C recommendation for the DOM supported by :mod:`xml.dom.minidom`.
 
-   `PyXML <http://pyxml.sourceforge.net>`_
-      Users that require a full-featured implementation of DOM should use the PyXML
-      package.
-
    `Python Language Mapping Specification <http://www.omg.org/docs/formal/02-11-05.pdf>`_
       This specifies the mapping from OMG IDL to Python.
 
@@ -364,8 +363,9 @@ All of the components of an XML document are subclasses of :class:`Node`.
 
 .. method:: Node.appendChild(newChild)
 
-   Add a new child node to this node at the end of the list of children, returning
-   *newChild*.
+   Add a new child node to this node at the end of the list of
+   children, returning *newChild*. If the node was already in
+   in the tree, it is removed first.
 
 
 .. method:: Node.insertBefore(newChild, refChild)
diff --git a/Doc/whatsnew/2.6.rst b/Doc/whatsnew/2.6.rst
index 4d52716..3415c1b 100644
--- a/Doc/whatsnew/2.6.rst
+++ b/Doc/whatsnew/2.6.rst
@@ -872,6 +872,10 @@ Build and C API Changes
 
 Changes to Python's build process and to the C API include:
 
+* Python 2.6 can be built with Microsoft Visual Studio 2008.
+  See the :file:`PCbuild9` directory for the build files.
+  (Implemented by Christian Heimes.)
+
 * The BerkeleyDB module now has a C API object, available as 
   ``bsddb.db.api``.   This object can be used by other C extensions
   that wish to use the :mod:`bsddb` module for their own purposes.
diff --git a/Lib/decimal.py b/Lib/decimal.py
index faf9bf7..7842cb2 100644
--- a/Lib/decimal.py
+++ b/Lib/decimal.py
@@ -214,10 +214,10 @@ class InvalidOperation(DecimalException):
     def handle(self, context, *args):
         if args:
             if args[0] == 1:  # sNaN, must drop 's' but keep diagnostics
-                ans = Decimal((args[1]._sign, args[1]._int, 'n'))
+                ans = _dec_from_triple(args[1]._sign, args[1]._int, 'n', True)
                 return ans._fix_nan(context)
             elif args[0] == 2:
-                return Decimal( (args[1], args[2], 'n') )
+                return _dec_from_triple(args[1], args[2], 'n', True)
         return NaN
 
 
@@ -350,13 +350,13 @@ class Overflow(Inexact, Rounded):
         if sign == 0:
             if context.rounding == ROUND_CEILING:
                 return Infsign[sign]
-            return Decimal((sign, (9,)*context.prec,
-                            context.Emax-context.prec+1))
+            return _dec_from_triple(sign, '9'*context.prec,
+                            context.Emax-context.prec+1)
         if sign == 1:
             if context.rounding == ROUND_FLOOR:
                 return Infsign[sign]
-            return Decimal( (sign, (9,)*context.prec,
-                             context.Emax-context.prec+1))
+            return _dec_from_triple(sign, '9'*context.prec,
+                             context.Emax-context.prec+1)
 
 
 class Underflow(Inexact, Rounded, Subnormal):
@@ -531,13 +531,21 @@ class Decimal(object):
         Decimal("314")
         """
 
+        # Note that the coefficient, self._int, is actually stored as
+        # a string rather than as a tuple of digits.  This speeds up
+        # the "digits to integer" and "integer to digits" conversions
+        # that are used in almost every arithmetic operation on
+        # Decimals.  This is an internal detail: the as_tuple function
+        # and the Decimal constructor still deal with tuples of
+        # digits.
+
         self = object.__new__(cls)
         self._is_special = False
 
         # From an internal working value
         if isinstance(value, _WorkRep):
             self._sign = value.sign
-            self._int = tuple(map(int, str(value.int)))
+            self._int = str(value.int)
             self._exp = int(value.exp)
             return self
 
@@ -556,7 +564,7 @@ class Decimal(object):
             else:
                 self._sign = 1
             self._exp = 0
-            self._int = tuple(map(int, str(abs(value))))
+            self._int = str(abs(value))
             return self
 
         # tuple/list conversion (possibly from as_tuple())
@@ -573,7 +581,7 @@ class Decimal(object):
             self._sign = value[0]
             if value[2] == 'F':
                 # infinity: value[1] is ignored
-                self._int = (0,)
+                self._int = '0'
                 self._exp = value[2]
                 self._is_special = True
             else:
@@ -590,12 +598,12 @@ class Decimal(object):
                                          "0 through 9.")
                 if value[2] in ('n', 'N'):
                     # NaN: digits form the diagnostic
-                    self._int = tuple(digits)
+                    self._int = ''.join(map(str, digits))
                     self._exp = value[2]
                     self._is_special = True
                 elif isinstance(value[2], int):
                     # finite number: digits give the coefficient
-                    self._int = tuple(digits or [0])
+                    self._int = ''.join(map(str, digits or [0]))
                     self._exp = value[2]
                     self._is_special = False
                 else:
@@ -608,38 +616,46 @@ class Decimal(object):
             raise TypeError("Cannot convert float to Decimal.  " +
                             "First convert the float to a string")
 
-        # Other argument types may require the context during interpretation
-        if context is None:
-            context = getcontext()
-
         # From a string
         # REs insist on real strings, so we can too.
         if isinstance(value, str):
-            if _isinfinity(value):
-                self._exp = 'F'
-                self._int = (0,)
-                self._is_special = True
-                if _isinfinity(value) == 1:
-                    self._sign = 0
+            m = _parser(value)
+            if m is None:
+                if context is None:
+                    context = getcontext()
+                return context._raise_error(ConversionSyntax,
+                                "Invalid literal for Decimal: %r" % value)
+
+            if m.group('sign') == "-":
+                self._sign = 1
+            else:
+                self._sign = 0
+            intpart = m.group('int')
+            if intpart is not None:
+                # finite number
+                fracpart = m.group('frac')
+                exp = int(m.group('exp') or '0')
+                if fracpart is not None:
+                    self._int = (intpart+fracpart).lstrip('0') or '0'
+                    self._exp = exp - len(fracpart)
                 else:
-                    self._sign = 1
-                return self
-            if _isnan(value):
-                sig, sign, diag = _isnan(value)
-                self._is_special = True
-                if sig == 1:
-                    self._exp = 'n'  # qNaN
-                else:  # sig == 2
-                    self._exp = 'N'  # sNaN
-                self._sign = sign
-                self._int = tuple(map(int, diag))  # Diagnostic info
-                return self
-            try:
-                self._sign, self._int, self._exp = _string2exact(value)
-            except ValueError:
+                    self._int = intpart.lstrip('0') or '0'
+                    self._exp = exp
+                self._is_special = False
+            else:
+                diag = m.group('diag')
+                if diag is not None:
+                    # NaN
+                    self._int = diag.lstrip('0')
+                    if m.group('signal'):
+                        self._exp = 'N'
+                    else:
+                        self._exp = 'n'
+                else:
+                    # infinity
+                    self._int = '0'
+                    self._exp = 'F'
                 self._is_special = True
-                return context._raise_error(ConversionSyntax,
-                                   "Invalid literal for Decimal: %r" % value)
             return self
 
         raise TypeError("Cannot convert %r to Decimal" % value)
@@ -709,7 +725,7 @@ class Decimal(object):
 
         NaNs and infinities are considered nonzero.
         """
-        return self._is_special or self._int[0] != 0
+        return self._is_special or self._int != '0'
 
     def __cmp__(self, other):
         other = _convert_other(other)
@@ -743,8 +759,8 @@ class Decimal(object):
         self_adjusted = self.adjusted()
         other_adjusted = other.adjusted()
         if self_adjusted == other_adjusted:
-            self_padded = self._int + (0,)*(self._exp - other._exp)
-            other_padded = other._int + (0,)*(other._exp - self._exp)
+            self_padded = self._int + '0'*(self._exp - other._exp)
+            other_padded = other._int + '0'*(other._exp - self._exp)
             return cmp(self_padded, other_padded) * (-1)**self._sign
         elif self_adjusted > other_adjusted:
             return (-1)**self._sign
@@ -827,7 +843,7 @@ class Decimal(object):
 
         To show the internals exactly as they are.
         """
-        return (self._sign, self._int, self._exp)
+        return (self._sign, tuple(map(int, self._int)), self._exp)
 
     def __repr__(self):
         """Represents the number as an instance of Decimal."""
@@ -843,10 +859,10 @@ class Decimal(object):
         if self._is_special:
             if self._isnan():
                 minus = '-'*self._sign
-                if self._int == (0,):
+                if self._int == '0':
                     info = ''
                 else:
-                    info = ''.join(map(str, self._int))
+                    info = self._int
                 if self._isnan() == 2:
                     return minus + 'sNaN' + info
                 return minus + 'NaN' + info
@@ -857,7 +873,7 @@ class Decimal(object):
         if context is None:
             context = getcontext()
 
-        tmp = list(map(str, self._int))
+        tmp = list(self._int)
         numdigits = len(self._int)
         leftdigits = self._exp + numdigits
         if eng and not self:  # self = 0eX wants 0[.0[0]]eY, not [[0]0]0eY
@@ -1030,7 +1046,7 @@ class Decimal(object):
             sign = min(self._sign, other._sign)
             if negativezero:
                 sign = 1
-            ans = Decimal( (sign, (0,), exp))
+            ans = _dec_from_triple(sign, '0', exp)
             if shouldround:
                 ans = ans._fix(context)
             return ans
@@ -1055,7 +1071,7 @@ class Decimal(object):
         if op1.sign != op2.sign:
             # Equal and opposite
             if op1.int == op2.int:
-                ans = Decimal((negativezero, (0,), exp))
+                ans = _dec_from_triple(negativezero, '0', exp)
                 if shouldround:
                     ans = ans._fix(context)
                 return ans
@@ -1121,7 +1137,7 @@ class Decimal(object):
         For example:
         Decimal('5.624e10')._increment() == Decimal('5.625e10')
         """
-        L = list(self._int)
+        L = list(map(int, self._int))
         L[-1] += 1
         spot = len(L)-1
         while L[spot] == 10:
@@ -1131,7 +1147,7 @@ class Decimal(object):
                 break
             L[spot-1] += 1
             spot -= 1
-        return Decimal((self._sign, L, self._exp))
+        return _dec_from_triple(self._sign, "".join(map(str, L)), self._exp)
 
     def __mul__(self, other, context=None):
         """Return self * other.
@@ -1167,20 +1183,20 @@ class Decimal(object):
 
         # Special case for multiplying by zero
         if not self or not other:
-            ans = Decimal((resultsign, (0,), resultexp))
+            ans = _dec_from_triple(resultsign, '0', resultexp)
             if shouldround:
                 # Fixing in case the exponent is out of bounds
                 ans = ans._fix(context)
             return ans
 
         # Special case for multiplying by power of 10
-        if self._int == (1,):
-            ans = Decimal((resultsign, other._int, resultexp))
+        if self._int == '1':
+            ans = _dec_from_triple(resultsign, other._int, resultexp)
             if shouldround:
                 ans = ans._fix(context)
             return ans
-        if other._int == (1,):
-            ans = Decimal((resultsign, self._int, resultexp))
+        if other._int == '1':
+            ans = _dec_from_triple(resultsign, self._int, resultexp)
             if shouldround:
                 ans = ans._fix(context)
             return ans
@@ -1188,9 +1204,7 @@ class Decimal(object):
         op1 = _WorkRep(self)
         op2 = _WorkRep(other)
 
-        ans = Decimal((resultsign,
-                       tuple(map(int, str(op1.int * op2.int))),
-                       resultexp))
+        ans = _dec_from_triple(resultsign, str(op1.int * op2.int), resultexp)
         if shouldround:
             ans = ans._fix(context)
 
@@ -1221,7 +1235,7 @@ class Decimal(object):
 
             if other._isinfinity():
                 context._raise_error(Clamped, 'Division by infinity')
-                return Decimal((sign, (0,), context.Etiny()))
+                return _dec_from_triple(sign, '0', context.Etiny())
 
         # Special cases for zeroes
         if not other:
@@ -1253,7 +1267,7 @@ class Decimal(object):
                     coeff //= 10
                     exp += 1
 
-        ans = Decimal((sign, list(map(int, str(coeff))), exp))
+        ans = _dec_from_triple(sign, str(coeff), exp)
         return ans._fix(context)
 
     def _divide(self, other, context):
@@ -1270,7 +1284,7 @@ class Decimal(object):
 
         expdiff = self.adjusted() - other.adjusted()
         if not self or other._isinfinity() or expdiff <= -2:
-            return (Decimal((sign, (0,), 0)),
+            return (_dec_from_triple(sign, '0', 0),
                     self._rescale(ideal_exp, context.rounding))
         if expdiff <= context.prec:
             op1 = _WorkRep(self)
@@ -1281,9 +1295,8 @@ class Decimal(object):
                 op2.int *= 10**(op2.exp - op1.exp)
             q, r = divmod(op1.int, op2.int)
             if q < 10**context.prec:
-                return (Decimal((sign, list(map(int, str(q))), 0)),
-                        Decimal((self._sign, list(map(int, str(r))),
-                                ideal_exp)))
+                return (_dec_from_triple(sign, str(q), 0),
+                        _dec_from_triple(self._sign, str(r), ideal_exp))
 
         # Here the quotient is too large to be representable
         ans = context._raise_error(DivisionImpossible,
@@ -1411,7 +1424,7 @@ class Decimal(object):
         # self = 0 -> remainder = self, with ideal exponent
         ideal_exponent = min(self._exp, other._exp)
         if not self:
-            ans = Decimal((self._sign, (0,), ideal_exponent))
+            ans = _dec_from_triple(self._sign, '0', ideal_exponent)
             return ans._fix(context)
 
         # catch most cases of large or small quotient
@@ -1448,7 +1461,7 @@ class Decimal(object):
             sign = 1-sign
             r = -r
 
-        ans = Decimal((sign, list(map(int, str(r))), ideal_exponent))
+        ans = _dec_from_triple(sign, str(r), ideal_exponent)
         return ans._fix(context)
 
     def __floordiv__(self, other, context=None):
@@ -1500,9 +1513,9 @@ class Decimal(object):
                 raise OverflowError("Cannot convert infinity to int")
         s = (-1)**self._sign
         if self._exp >= 0:
-            return s*int(''.join(map(str, self._int)))*10**self._exp
+            return s*int(self._int)*10**self._exp
         else:
-            return s*int(''.join(map(str, self._int))[:self._exp] or '0')
+            return s*int(self._int[:self._exp] or '0')
 
     def _fix_nan(self, context):
         """Decapitate the payload of a NaN to fit the context"""
@@ -1512,11 +1525,8 @@ class Decimal(object):
         # precision-1 if _clamp=1.
         max_payload_len = context.prec - context._clamp
         if len(payload) > max_payload_len:
-            pos = len(payload)-max_payload_len
-            while pos < len(payload) and payload[pos] == 0:
-                pos += 1
-            payload = payload[pos:]
-            return Decimal((self._sign, payload, self._exp))
+            payload = payload[len(payload)-max_payload_len:].lstrip('0')
+            return _dec_from_triple(self._sign, payload, self._exp, True)
         return Decimal(self)
 
     def _fix(self, context):
@@ -1549,7 +1559,7 @@ class Decimal(object):
             new_exp = min(max(self._exp, Etiny), exp_max)
             if new_exp != self._exp:
                 context._raise_error(Clamped)
-                return Decimal((self._sign, (0,), new_exp))
+                return _dec_from_triple(self._sign, '0', new_exp)
             else:
                 return Decimal(self)
 
@@ -1581,7 +1591,8 @@ class Decimal(object):
                     # we get here only if rescaling rounds the
                     # cofficient up to exactly 10**context.prec
                     if ans._exp < Etop:
-                        ans = Decimal((ans._sign, ans._int[:-1], ans._exp+1))
+                        ans = _dec_from_triple(ans._sign,
+                                                   ans._int[:-1], ans._exp+1)
                     else:
                         # Inexact and Rounded have already been raised
                         ans = context._raise_error(Overflow, 'above Emax',
@@ -1591,8 +1602,8 @@ class Decimal(object):
         # fold down if _clamp == 1 and self has too few digits
         if context._clamp == 1 and self._exp > Etop:
             context._raise_error(Clamped)
-            self_padded = self._int + (0,)*(self._exp - Etop)
-            return Decimal((self._sign, self_padded, Etop))
+            self_padded = self._int + '0'*(self._exp - Etop)
+            return _dec_from_triple(self._sign, self_padded, Etop)
 
         # here self was representable to begin with; return unchanged
         return Decimal(self)
@@ -1607,29 +1618,29 @@ class Decimal(object):
     def _round_down(self, prec):
         """Also known as round-towards-0, truncate."""
         newexp = self._exp + len(self._int) - prec
-        return Decimal((self._sign, self._int[:prec] or (0,), newexp))
+        return _dec_from_triple(self._sign, self._int[:prec] or '0', newexp)
 
     def _round_up(self, prec):
         """Rounds away from 0."""
         newexp = self._exp + len(self._int) - prec
-        tmp = Decimal((self._sign, self._int[:prec] or (0,), newexp))
+        tmp = _dec_from_triple(self._sign, self._int[:prec] or '0', newexp)
         for digit in self._int[prec:]:
-            if digit != 0:
+            if digit != '0':
                 return tmp._increment()
         return tmp
 
     def _round_half_up(self, prec):
         """Rounds 5 up (away from 0)"""
-        if self._int[prec] >= 5:
+        if self._int[prec] in '56789':
             return self._round_up(prec)
         else:
             return self._round_down(prec)
 
     def _round_half_down(self, prec):
         """Round 5 down"""
-        if self._int[prec] == 5:
+        if self._int[prec] == '5':
             for digit in self._int[prec+1:]:
-                if digit != 0:
+                if digit != '0':
                     break
             else:
                 return self._round_down(prec)
@@ -1637,7 +1648,7 @@ class Decimal(object):
 
     def _round_half_even(self, prec):
         """Round 5 to even, rest to nearest."""
-        if prec and self._int[prec-1] & 1:
+        if prec and self._int[prec-1] in '13579':
             return self._round_half_up(prec)
         else:
             return self._round_half_down(prec)
@@ -1658,7 +1669,7 @@ class Decimal(object):
 
     def _round_05up(self, prec):
         """Round down unless digit prec-1 is 0 or 5."""
-        if prec == 0 or self._int[prec-1] in (0, 5):
+        if prec == 0 or self._int[prec-1] in '05':
             return self._round_up(prec)
         else:
             return self._round_down(prec)
@@ -1776,7 +1787,7 @@ class Decimal(object):
             base = pow(base, 10, modulo)
         base = pow(base, exponent.int, modulo)
 
-        return Decimal((sign, list(map(int, str(base))), 0))
+        return _dec_from_triple(sign, str(base), 0)
 
     def _power_exact(self, other, p):
         """Attempt to compute self**other exactly.
@@ -1866,7 +1877,7 @@ class Decimal(object):
                 zeros = min(exponent-ideal_exponent, p-1)
             else:
                 zeros = 0
-            return Decimal((0, (1,) + (0,)*zeros, exponent-zeros))
+            return _dec_from_triple(0, '1' + '0'*zeros, exponent-zeros)
 
         # case where y is negative: xc must be either a power
         # of 2 or a power of 5.
@@ -1927,7 +1938,7 @@ class Decimal(object):
             if xc >= 10**p:
                 return None
             xe = -e-xe
-            return Decimal((0, list(map(int, str(xc))), xe))
+            return _dec_from_triple(0, str(xc), xe)
 
         # now y is positive; find m and n such that y = m/n
         if ye >= 0:
@@ -1989,7 +2000,7 @@ class Decimal(object):
             zeros = min(xe-ideal_exponent, p-len(str_xc))
         else:
             zeros = 0
-        return Decimal((0, list(map(int, str_xc))+[0,]*zeros, xe-zeros))
+        return _dec_from_triple(0, str_xc+'0'*zeros, xe-zeros)
 
     def __pow__(self, other, modulo=None, context=None):
         """Return self ** other [ % modulo].
@@ -2050,12 +2061,12 @@ class Decimal(object):
                     return context._raise_error(InvalidOperation,
                         'x ** y with x negative and y not an integer')
             # negate self, without doing any unwanted rounding
-            self = Decimal((0, self._int, self._exp))
+            self = self.copy_negate()
 
         # 0**(+ve or Inf)= 0; 0**(-ve or -Inf) = Infinity
         if not self:
             if other._sign == 0:
-                return Decimal((result_sign, (0,), 0))
+                return _dec_from_triple(result_sign, '0', 0)
             else:
                 return Infsign[result_sign]
 
@@ -2064,7 +2075,7 @@ class Decimal(object):
             if other._sign == 0:
                 return Infsign[result_sign]
             else:
-                return Decimal((result_sign, (0,), 0))
+                return _dec_from_triple(result_sign, '0', 0)
 
         # 1**other = 1, but the choice of exponent and the flags
         # depend on the exponent of self, and on whether other is a
@@ -2091,7 +2102,7 @@ class Decimal(object):
                 context._raise_error(Rounded)
                 exp = 1-context.prec
 
-            return Decimal((result_sign, (1,)+(0,)*-exp, exp))
+            return _dec_from_triple(result_sign, '1'+'0'*-exp, exp)
 
         # compute adjusted exponent of self
         self_adj = self.adjusted()
@@ -2100,7 +2111,7 @@ class Decimal(object):
         # self ** -infinity is infinity if self < 1, 0 if self > 1
         if other._isinfinity():
             if (other._sign == 0) == (self_adj < 0):
-                return Decimal((result_sign, (0,), 0))
+                return _dec_from_triple(result_sign, '0', 0)
             else:
                 return Infsign[result_sign]
 
@@ -2118,19 +2129,19 @@ class Decimal(object):
             # self > 1 and other +ve, or self < 1 and other -ve
             # possibility of overflow
             if bound >= len(str(context.Emax)):
-                ans = Decimal((result_sign, (1,), context.Emax+1))
+                ans = _dec_from_triple(result_sign, '1', context.Emax+1)
         else:
             # self > 1 and other -ve, or self < 1 and other +ve
             # possibility of underflow to 0
             Etiny = context.Etiny()
             if bound >= len(str(-Etiny)):
-                ans = Decimal((result_sign, (1,), Etiny-1))
+                ans = _dec_from_triple(result_sign, '1', Etiny-1)
 
         # try for an exact result with precision +1
         if ans is None:
             ans = self._power_exact(other, context.prec + 1)
             if ans is not None and result_sign == 1:
-                ans = Decimal((1, ans._int, ans._exp))
+                ans = _dec_from_triple(1, ans._int, ans._exp)
 
         # usual case: inexact result, x**y computed directly as exp(y*log(x))
         if ans is None:
@@ -2151,7 +2162,7 @@ class Decimal(object):
                     break
                 extra += 3
 
-            ans = Decimal((result_sign, list(map(int, str(coeff))), exp))
+            ans = _dec_from_triple(result_sign, str(coeff), exp)
 
         # the specification says that for non-integer other we need to
         # raise Inexact, even when the result is actually exact.  In
@@ -2163,7 +2174,8 @@ class Decimal(object):
             # pad with zeros up to length context.prec+1 if necessary
             if len(ans._int) <= context.prec:
                 expdiff = context.prec+1 - len(ans._int)
-                ans = Decimal((ans._sign, ans._int+(0,)*expdiff, ans._exp-expdiff))
+                ans = _dec_from_triple(ans._sign, ans._int+'0'*expdiff,
+                                       ans._exp-expdiff)
             if ans.adjusted() < context.Emin:
                 context._raise_error(Underflow)
 
@@ -2195,14 +2207,14 @@ class Decimal(object):
             return dup
 
         if not dup:
-            return Decimal( (dup._sign, (0,), 0) )
+            return _dec_from_triple(dup._sign, '0', 0)
         exp_max = [context.Emax, context.Etop()][context._clamp]
         end = len(dup._int)
         exp = dup._exp
-        while dup._int[end-1] == 0 and exp < exp_max:
+        while dup._int[end-1] == '0' and exp < exp_max:
             exp += 1
             end -= 1
-        return Decimal( (dup._sign, dup._int[:end], exp) )
+        return _dec_from_triple(dup._sign, dup._int[:end], exp)
 
     def quantize(self, exp, rounding=None, context=None, watchexp=True):
         """Quantize self so its exponent is the same as that of exp.
@@ -2243,7 +2255,7 @@ class Decimal(object):
                    'target exponent out of bounds in quantize')
 
         if not self:
-            ans = Decimal((self._sign, (0,), exp._exp))
+            ans = _dec_from_triple(self._sign, '0', exp._exp)
             return ans._fix(context)
 
         self_adjusted = self.adjusted()
@@ -2303,17 +2315,18 @@ class Decimal(object):
         if self._is_special:
             return Decimal(self)
         if not self:
-            return Decimal((self._sign, (0,), exp))
+            return _dec_from_triple(self._sign, '0', exp)
 
         if self._exp >= exp:
             # pad answer with zeros if necessary
-            return Decimal((self._sign, self._int + (0,)*(self._exp - exp), exp))
+            return _dec_from_triple(self._sign,
+                                        self._int + '0'*(self._exp - exp), exp)
 
         # too many digits; round and lose data.  If self.adjusted() <
         # exp-1, replace self by 10**(exp-1) before rounding
         digits = len(self._int) + self._exp - exp
         if digits < 0:
-            self = Decimal((self._sign, (1,), exp-1))
+            self = _dec_from_triple(self._sign, '1', exp-1)
             digits = 0
         this_function = getattr(self, self._pick_rounding_function[rounding])
         return this_function(digits)
@@ -2336,7 +2349,7 @@ class Decimal(object):
         if self._exp >= 0:
             return Decimal(self)
         if not self:
-            return Decimal((self._sign, (0,), 0))
+            return _dec_from_triple(self._sign, '0', 0)
         if context is None:
             context = getcontext()
         if rounding is None:
@@ -2378,7 +2391,7 @@ class Decimal(object):
 
         if not self:
             # exponent = self._exp // 2.  sqrt(-0) = -0
-            ans = Decimal((self._sign, (0,), self._exp // 2))
+            ans = _dec_from_triple(self._sign, '0', self._exp // 2)
             return ans._fix(context)
 
         if context is None:
@@ -2455,7 +2468,7 @@ class Decimal(object):
             if n % 5 == 0:
                 n += 1
 
-        ans = Decimal((0, list(map(int, str(n))), e))
+        ans = _dec_from_triple(0, str(n), e)
 
         # round, and fit to current context
         context = context._shallow_copy()
@@ -2552,13 +2565,13 @@ class Decimal(object):
         if self._exp >= 0:
             return True
         rest = self._int[self._exp:]
-        return rest == (0,)*len(rest)
+        return rest == '0'*len(rest)
 
     def _iseven(self):
         """Returns True if self is even.  Assumes self is an integer."""
         if not self or self._exp > 0:
             return True
-        return self._int[-1+self._exp] & 1 == 0
+        return self._int[-1+self._exp] in '02468'
 
     def adjusted(self):
         """Return the adjusted exponent of self"""
@@ -2680,18 +2693,19 @@ class Decimal(object):
 
     def copy_abs(self):
         """Returns a copy with the sign set to 0. """
-        return Decimal((0, self._int, self._exp))
+        return _dec_from_triple(0, self._int, self._exp, self._is_special)
 
     def copy_negate(self):
         """Returns a copy with the sign inverted."""
         if self._sign:
-            return Decimal((0, self._int, self._exp))
+            return _dec_from_triple(0, self._int, self._exp, self._is_special)
         else:
-            return Decimal((1, self._int, self._exp))
+            return _dec_from_triple(1, self._int, self._exp, self._is_special)
 
     def copy_sign(self, other):
         """Returns self with the sign of other."""
-        return Decimal((other._sign, self._int, self._exp))
+        return _dec_from_triple(other._sign, self._int,
+                                self._exp, self._is_special)
 
     def exp(self, context=None):
         """Returns e ** self."""
@@ -2730,16 +2744,16 @@ class Decimal(object):
         # larger exponent the result either overflows or underflows.
         if self._sign == 0 and adj > len(str((context.Emax+1)*3)):
             # overflow
-            ans = Decimal((0, (1,), context.Emax+1))
+            ans = _dec_from_triple(0, '1', context.Emax+1)
         elif self._sign == 1 and adj > len(str((-context.Etiny()+1)*3)):
             # underflow to 0
-            ans = Decimal((0, (1,), context.Etiny()-1))
+            ans = _dec_from_triple(0, '1', context.Etiny()-1)
         elif self._sign == 0 and adj < -p:
             # p+1 digits; final round will raise correct flags
-            ans = Decimal((0, (1,) + (0,)*(p-1) + (1,), -p))
+            ans = _dec_from_triple(0, '1' + '0'*(p-1) + '1', -p)
         elif self._sign == 1 and adj < -p-1:
             # p+1 digits; final round will raise correct flags
-            ans = Decimal((0, (9,)*(p+1), -p-1))
+            ans = _dec_from_triple(0, '9'*(p+1), -p-1)
         # general case
         else:
             op = _WorkRep(self)
@@ -2757,7 +2771,7 @@ class Decimal(object):
                     break
                 extra += 3
 
-            ans = Decimal((0, list(map(int, str(coeff))), exp))
+            ans = _dec_from_triple(0, str(coeff), exp)
 
         # at this stage, ans should round correctly with *any*
         # rounding mode, not just with ROUND_HALF_EVEN
@@ -2822,7 +2836,7 @@ class Decimal(object):
 
     def is_zero(self):
         """Return True if self is a zero; otherwise return False."""
-        return not self._is_special and self._int[0] == 0
+        return not self._is_special and self._int == '0'
 
     def _ln_exp_bound(self):
         """Compute a lower bound for the adjusted exponent of self.ln().
@@ -2891,7 +2905,7 @@ class Decimal(object):
             if coeff % (5*10**(len(str(abs(coeff)))-p-1)):
                 break
             places += 3
-        ans = Decimal((int(coeff<0), list(map(int, str(abs(coeff)))), -places))
+        ans = _dec_from_triple(int(coeff<0), str(abs(coeff)), -places)
 
         context = context._shallow_copy()
         rounding = context._set_rounding(ROUND_HALF_EVEN)
@@ -2954,7 +2968,7 @@ class Decimal(object):
                                         'log10 of a negative value')
 
         # log10(10**n) = n
-        if self._int[0] == 1 and self._int[1:] == (0,)*(len(self._int) - 1):
+        if self._int[0] == '1' and self._int[1:] == '0'*(len(self._int) - 1):
             # answer may need rounding
             ans = Decimal(self._exp + len(self._int) - 1)
         else:
@@ -2972,8 +2986,7 @@ class Decimal(object):
                 if coeff % (5*10**(len(str(abs(coeff)))-p-1)):
                     break
                 places += 3
-            ans = Decimal((int(coeff<0), list(map(int, str(abs(coeff)))),
-                          -places))
+            ans = _dec_from_triple(int(coeff<0), str(abs(coeff)), -places)
 
         context = context._shallow_copy()
         rounding = context._set_rounding(ROUND_HALF_EVEN)
@@ -3020,19 +3033,19 @@ class Decimal(object):
         if self._sign != 0 or self._exp != 0:
             return False
         for dig in self._int:
-            if dig not in (0, 1):
+            if dig not in '01':
                 return False
         return True
 
     def _fill_logical(self, context, opa, opb):
         dif = context.prec - len(opa)
         if dif > 0:
-            opa = (0,)*dif + opa
+            opa = '0'*dif + opa
         elif dif < 0:
             opa = opa[-context.prec:]
         dif = context.prec - len(opb)
         if dif > 0:
-            opb = (0,)*dif + opb
+            opb = '0'*dif + opb
         elif dif < 0:
             opb = opb[-context.prec:]
         return opa, opb
@@ -3048,22 +3061,15 @@ class Decimal(object):
         (opa, opb) = self._fill_logical(context, self._int, other._int)
 
         # make the operation, and clean starting zeroes
-        result = [a&b for a,b in zip(opa,opb)]
-        for i,d in enumerate(result):
-            if d == 1:
-                break
-        result = tuple(result[i:])
-
-        # if empty, we must have at least a zero
-        if not result:
-            result = (0,)
-        return Decimal((0, result, 0))
+        result = "".join([str(int(a)&int(b)) for a,b in zip(opa,opb)])
+        return _dec_from_triple(0, result.lstrip('0') or '0', 0)
 
     def logical_invert(self, context=None):
         """Invert all its digits."""
         if context is None:
             context = getcontext()
-        return self.logical_xor(Decimal((0,(1,)*context.prec,0)), context)
+        return self.logical_xor(_dec_from_triple(0,'1'*context.prec,0),
+                                context)
 
     def logical_or(self, other, context=None):
         """Applies an 'or' operation between self and other's digits."""
@@ -3076,16 +3082,8 @@ class Decimal(object):
         (opa, opb) = self._fill_logical(context, self._int, other._int)
 
         # make the operation, and clean starting zeroes
-        result = [a|b for a,b in zip(opa,opb)]
-        for i,d in enumerate(result):
-            if d == 1:
-                break
-        result = tuple(result[i:])
-
-        # if empty, we must have at least a zero
-        if not result:
-            result = (0,)
-        return Decimal((0, result, 0))
+        result = "".join(str(int(a)|int(b)) for a,b in zip(opa,opb))
+        return _dec_from_triple(0, result.lstrip('0') or '0', 0)
 
     def logical_xor(self, other, context=None):
         """Applies an 'xor' operation between self and other's digits."""
@@ -3098,16 +3096,8 @@ class Decimal(object):
         (opa, opb) = self._fill_logical(context, self._int, other._int)
 
         # make the operation, and clean starting zeroes
-        result = [a^b for a,b in zip(opa,opb)]
-        for i,d in enumerate(result):
-            if d == 1:
-                break
-        result = tuple(result[i:])
-
-        # if empty, we must have at least a zero
-        if not result:
-            result = (0,)
-        return Decimal((0, result, 0))
+        result = "".join(str(int(a)^int(b)) for a,b in zip(opa,opb))
+        return _dec_from_triple(0, result.lstrip('0') or '0', 0)
 
     def max_mag(self, other, context=None):
         """Compares the values numerically with their sign ignored."""
@@ -3185,7 +3175,7 @@ class Decimal(object):
         if self._isinfinity() == -1:
             return negInf
         if self._isinfinity() == 1:
-            return Decimal((0, (9,)*context.prec, context.Etop()))
+            return _dec_from_triple(0, '9'*context.prec, context.Etop())
 
         context = context.copy()
         context._set_rounding(ROUND_FLOOR)
@@ -3193,7 +3183,8 @@ class Decimal(object):
         new_self = self._fix(context)
         if new_self != self:
             return new_self
-        return self.__sub__(Decimal((0, (1,), context.Etiny()-1)), context)
+        return self.__sub__(_dec_from_triple(0, '1', context.Etiny()-1),
+                            context)
 
     def next_plus(self, context=None):
         """Returns the smallest representable number larger than itself."""
@@ -3207,7 +3198,7 @@ class Decimal(object):
         if self._isinfinity() == 1:
             return Inf
         if self._isinfinity() == -1:
-            return Decimal((1, (9,)*context.prec, context.Etop()))
+            return _dec_from_triple(1, '9'*context.prec, context.Etop())
 
         context = context.copy()
         context._set_rounding(ROUND_CEILING)
@@ -3215,7 +3206,8 @@ class Decimal(object):
         new_self = self._fix(context)
         if new_self != self:
             return new_self
-        return self.__add__(Decimal((0, (1,), context.Etiny()-1)), context)
+        return self.__add__(_dec_from_triple(0, '1', context.Etiny()-1),
+                            context)
 
     def next_toward(self, other, context=None):
         """Returns the number closest to self, in the direction towards other.
@@ -3237,7 +3229,7 @@ class Decimal(object):
 
         comparison = self.__cmp__(other)
         if comparison == 0:
-            return Decimal((other._sign, self._int, self._exp))
+            return self.copy_sign(other)
 
         if comparison == -1:
             ans = self.next_plus(context)
@@ -3331,19 +3323,12 @@ class Decimal(object):
         rotdig = self._int
         topad = context.prec - len(rotdig)
         if topad:
-            rotdig = ((0,)*topad) + rotdig
+            rotdig = '0'*topad + rotdig
 
         # let's rotate!
         rotated = rotdig[torot:] + rotdig[:torot]
-
-        # clean starting zeroes
-        for i,d in enumerate(rotated):
-            if d != 0:
-                break
-        rotated = rotated[i:]
-
-        return Decimal((self._sign, rotated, self._exp))
-
+        return _dec_from_triple(self._sign,
+                                rotated.lstrip('0') or '0', self._exp)
 
     def scaleb (self, other, context=None):
         """Returns self operand after adding the second value to its exp."""
@@ -3364,7 +3349,7 @@ class Decimal(object):
         if self._isinfinity():
             return Decimal(self)
 
-        d = Decimal((self._sign, self._int, self._exp + int(other)))
+        d = _dec_from_triple(self._sign, self._int, self._exp + int(other))
         d = d._fix(context)
         return d
 
@@ -3392,26 +3377,17 @@ class Decimal(object):
         rotdig = self._int
         topad = context.prec - len(rotdig)
         if topad:
-            rotdig = ((0,)*topad) + rotdig
+            rotdig = '0'*topad + rotdig
 
         # let's shift!
         if torot < 0:
             rotated = rotdig[:torot]
         else:
-            rotated = (rotdig + ((0,) * torot))
+            rotated = rotdig + '0'*torot
             rotated = rotated[-context.prec:]
 
-        # clean starting zeroes
-        if rotated:
-            for i,d in enumerate(rotated):
-                if d != 0:
-                    break
-            rotated = rotated[i:]
-        else:
-            rotated = (0,)
-
-        return Decimal((self._sign, rotated, self._exp))
-
+        return _dec_from_triple(self._sign,
+                                    rotated.lstrip('0') or '0', self._exp)
 
     # Support for pickling, copy, and deepcopy
     def __reduce__(self):
@@ -3427,6 +3403,22 @@ class Decimal(object):
             return self     # My components are also immutable
         return self.__class__(str(self))
 
+def _dec_from_triple(sign, coefficient, exponent, special=False):
+    """Create a decimal instance directly, without any validation,
+    normalization (e.g. removal of leading zeros) or argument
+    conversion.
+
+    This function is for *internal use only*.
+    """
+
+    self = object.__new__(Decimal)
+    self._sign = sign
+    self._int = coefficient
+    self._exp = exponent
+    self._is_special = special
+
+    return self
+
 ##### Context class #######################################################
 
 
@@ -4775,10 +4767,7 @@ class _WorkRep(object):
             self.exp = None
         elif isinstance(value, Decimal):
             self.sign = value._sign
-            cum = 0
-            for digit  in value._int:
-                cum = cum * 10 + digit
-            self.int = cum
+            self.int = int(value._int)
             self.exp = value._exp
         else:
             # assert isinstance(value, tuple)
@@ -5175,53 +5164,6 @@ def _convert_other(other, raiseit=False):
         raise TypeError("Unable to convert %s to Decimal" % other)
     return NotImplemented
 
-_infinity_map = {
-    'inf' : 1,
-    'infinity' : 1,
-    '+inf' : 1,
-    '+infinity' : 1,
-    '-inf' : -1,
-    '-infinity' : -1
-}
-
-def _isinfinity(num):
-    """Determines whether a string or float is infinity.
-
-    +1 for negative infinity; 0 for finite ; +1 for positive infinity
-    """
-    num = str(num).lower()
-    return _infinity_map.get(num, 0)
-
-def _isnan(num):
-    """Determines whether a string or float is NaN
-
-    (1, sign, diagnostic info as string) => NaN
-    (2, sign, diagnostic info as string) => sNaN
-    0 => not a NaN
-    """
-    num = str(num).lower()
-    if not num:
-        return 0
-
-    # Get the sign, get rid of trailing [+-]
-    sign = 0
-    if num[0] == '+':
-        num = num[1:]
-    elif num[0] == '-':  # elif avoids '+-nan'
-        num = num[1:]
-        sign = 1
-
-    if num.startswith('nan'):
-        if len(num) > 3 and not num[3:].isdigit():  # diagnostic info
-            return 0
-        return (1, sign, num[3:].lstrip('0'))
-    if num.startswith('snan'):
-        if len(num) > 4 and not num[4:].isdigit():
-            return 0
-        return (2, sign, num[4:].lstrip('0'))
-    return 0
-
-
 ##### Setup Specific Contexts ############################################
 
 # The default context prototype used by Context()
@@ -5255,91 +5197,62 @@ ExtendedContext = Context(
 )
 
 
-##### Useful Constants (internal use only) ################################
-
-# Reusable defaults
-Inf = Decimal('Inf')
-negInf = Decimal('-Inf')
-NaN = Decimal('NaN')
-Dec_0 = Decimal(0)
-Dec_p1 = Decimal(1)
-Dec_n1 = Decimal(-1)
-Dec_p2 = Decimal(2)
-Dec_n2 = Decimal(-2)
-
-# Infsign[sign] is infinity w/ that sign
-Infsign = (Inf, negInf)
-
-
 ##### crud for parsing strings #############################################
 import re
 
-# There's an optional sign at the start, and an optional exponent
-# at the end.  The exponent has an optional sign and at least one
-# digit.  In between, must have either at least one digit followed
-# by an optional fraction, or a decimal point followed by at least
-# one digit.  Yuck.
+# Regular expression used for parsing numeric strings.  Additional
+# comments:
+#
+# 1. Uncomment the two '\s*' lines to allow leading and/or trailing
+# whitespace.  But note that the specification disallows whitespace in
+# a numeric string.
+#
+# 2. For finite numbers (not infinities and NaNs) the body of the
+# number between the optional sign and the optional exponent must have
+# at least one decimal digit, possibly after the decimal point.  The
+# lookahead expression '(?=\d|\.\d)' checks this.
+#
+# As the flag UNICODE is not enabled here, we're explicitly avoiding any
+# other meaning for \d than the numbers [0-9].
 
-_parser = re.compile(r"""
+import re
+_parser = re.compile(r"""     # A numeric string consists of:
 #    \s*
-    (?P<sign>[-+])?
+    (?P<sign>[-+])?           # an optional sign, followed by either...
     (
-        (?P<int>\d+) (\. (?P<frac>\d*))?
+        (?=\d|\.\d)           # ...a number (with at least one digit)
+        (?P<int>\d*)          # consisting of a (possibly empty) integer part
+        (\.(?P<frac>\d*))?    # followed by an optional fractional part
+        (E(?P<exp>[-+]?\d+))? # followed by an optional exponent, or...
     |
-        \. (?P<onlyfrac>\d+)
+        Inf(inity)?           # ...an infinity, or...
+    |
+        (?P<signal>s)?        # ...an (optionally signaling)
+        NaN                   # NaN
+        (?P<diag>\d*)         # with (possibly empty) diagnostic information.
     )
-    ([eE](?P<exp>[-+]? \d+))?
 #    \s*
     $
-""", re.VERBOSE).match  # Uncomment the \s* to allow leading or trailing spaces.
+""", re.VERBOSE | re.IGNORECASE).match
 
 del re
 
-def _string2exact(s):
-    """Return sign, n, p s.t.
 
-    Float string value == -1**sign * n * 10**p exactly
-    """
-    m = _parser(s)
-    if m is None:
-        raise ValueError("invalid literal for Decimal: %r" % s)
+##### Useful Constants (internal use only) ################################
 
-    if m.group('sign') == "-":
-        sign = 1
-    else:
-        sign = 0
+# Reusable defaults
+Inf = Decimal('Inf')
+negInf = Decimal('-Inf')
+NaN = Decimal('NaN')
+Dec_0 = Decimal(0)
+Dec_p1 = Decimal(1)
+Dec_n1 = Decimal(-1)
+Dec_p2 = Decimal(2)
+Dec_n2 = Decimal(-2)
 
-    exp = m.group('exp')
-    if exp is None:
-        exp = 0
-    else:
-        exp = int(exp)
+# Infsign[sign] is infinity w/ that sign
+Infsign = (Inf, negInf)
 
-    intpart = m.group('int')
-    if intpart is None:
-        intpart = ""
-        fracpart = m.group('onlyfrac')
-    else:
-        fracpart = m.group('frac')
-        if fracpart is None:
-            fracpart = ""
-
-    exp -= len(fracpart)
-
-    mantissa = intpart + fracpart
-    tmp = list(map(int, mantissa))
-    backup = tmp
-    while tmp and tmp[0] == 0:
-        del tmp[0]
-
-    # It's a zero
-    if not tmp:
-        if backup:
-            return (sign, tuple(backup), exp)
-        return (sign, (0,), exp)
-    mantissa = tuple(tmp)
-
-    return (sign, mantissa, exp)
 
 
 if __name__ == '__main__':
diff --git a/Lib/doctest.py b/Lib/doctest.py
index eee2f51..5b18073 100644
--- a/Lib/doctest.py
+++ b/Lib/doctest.py
@@ -315,8 +315,21 @@ class _OutputRedirectingPdb(pdb.Pdb):
     """
     def __init__(self, out):
         self.__out = out
+        self.__debugger_used = False
         pdb.Pdb.__init__(self, stdout=out)
 
+    def set_trace(self, frame=None):
+        self.__debugger_used = True
+        if frame is None:
+            frame = sys._getframe().f_back
+        pdb.Pdb.set_trace(self, frame)
+
+    def set_continue(self):
+        # Calling set_continue unconditionally would break unit test
+        # coverage reporting, as Bdb.set_continue calls sys.settrace(None).
+        if self.__debugger_used:
+            pdb.Pdb.set_continue(self)
+
     def trace_dispatch(self, *args):
         # Redirect stdout to the given stream.
         save_stdout = sys.stdout
diff --git a/Lib/test/decimaltestdata/abs.decTest b/Lib/test/decimaltestdata/abs.decTest
index ed4c46e..39f2dca 100644
--- a/Lib/test/decimaltestdata/abs.decTest
+++ b/Lib/test/decimaltestdata/abs.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests primarily tests the existence of the operator.
 -- Additon, subtraction, rounding, and more overflows are tested
diff --git a/Lib/test/decimaltestdata/add.decTest b/Lib/test/decimaltestdata/add.decTest
index 3460aa4..8db222a 100644
--- a/Lib/test/decimaltestdata/add.decTest
+++ b/Lib/test/decimaltestdata/add.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   9
 rounding:    half_up
@@ -1122,6 +1122,15 @@ addx1116 add -1e-3 +1e-383   -> -0.0009999999999999999  Rounded Inexact
 addx1117 add -1e-4 +1e-383   -> -0.00009999999999999999  Rounded Inexact
 addx1118 add -1e-5 +1e-383   -> -0.000009999999999999999  Rounded Inexact
 addx1119 add -1e-6 +1e-383   -> -9.999999999999999E-7  Rounded Inexact
+addx1120 add +1e-383 -1e+2   -> -99.99999999999999 Rounded Inexact
+addx1121 add +1e-383 -1e+1   -> -9.999999999999999  Rounded Inexact
+addx1123 add +1e-383    -1   -> -0.9999999999999999  Rounded Inexact
+addx1124 add +1e-383 -1e-1   -> -0.09999999999999999  Rounded Inexact
+addx1125 add +1e-383 -1e-2   -> -0.009999999999999999  Rounded Inexact
+addx1126 add +1e-383 -1e-3   -> -0.0009999999999999999  Rounded Inexact
+addx1127 add +1e-383 -1e-4   -> -0.00009999999999999999  Rounded Inexact
+addx1128 add +1e-383 -1e-5   -> -0.000009999999999999999  Rounded Inexact
+addx1129 add +1e-383 -1e-6   -> -9.999999999999999E-7  Rounded Inexact
 
 rounding:     down
 precision:    7
@@ -1658,17 +1667,19 @@ addx6056 add '1.3' '-2.07' -> '-0.77'
 addx6057 add '1E+2' '1E+4' -> '1.01E+4'
 
 -- from above
-addx6061 add 1 '0.1' -> '1.1'
-addx6062 add 1 '0.01' -> '1.01'
-addx6063 add 1 '0.001' -> '1.001'
-addx6064 add 1 '0.0001' -> '1.0001'
-addx6065 add 1 '0.00001' -> '1.00001'
-addx6066 add 1 '0.000001' -> '1.000001'
-addx6067 add 1 '0.0000001' -> '1.0000001'
-addx6068 add 1 '0.00000001' -> '1.00000001'
+addx6060 add 1 '0.1' -> '1.1'
+addx6061 add 1 '0.01' -> '1.01'
+addx6062 add 1 '0.001' -> '1.001'
+addx6063 add 1 '0.0001' -> '1.0001'
+addx6064 add 1 '0.00001' -> '1.00001'
+addx6065 add 1 '0.000001' -> '1.000001'
+addx6066 add 1 '0.0000001' -> '1.0000001'
+addx6067 add 1 '0.00000001' -> '1.00000001'
 
 -- cancellation to integer
-addx6069 add 99999999999999123456789 -99999999999999E+9 -> 123456789
+addx6068 add 99999999999999123456789 -99999999999999E+9 -> 123456789
+-- similar from FMA fun
+addx6069 add "-1234567890123455.234567890123454" "1234567890123456" -> 0.765432109876546
 
 -- some funny zeros [in case of bad signum]
 addx6070 add 1  0    -> 1
diff --git a/Lib/test/decimaltestdata/and.decTest b/Lib/test/decimaltestdata/and.decTest
index 18ba881..90490a5 100644
--- a/Lib/test/decimaltestdata/and.decTest
+++ b/Lib/test/decimaltestdata/and.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/base.decTest b/Lib/test/decimaltestdata/base.decTest
index de0b813..58ce91c 100644
--- a/Lib/test/decimaltestdata/base.decTest
+++ b/Lib/test/decimaltestdata/base.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 extended:    1
 
 -- This file tests base conversions from string to a decimal number
diff --git a/Lib/test/decimaltestdata/clamp.decTest b/Lib/test/decimaltestdata/clamp.decTest
index eca0cfb..48e27c0 100644
--- a/Lib/test/decimaltestdata/clamp.decTest
+++ b/Lib/test/decimaltestdata/clamp.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests uses the same limits as the 8-byte concrete
 -- representation, but applies clamping without using format-specific
diff --git a/Lib/test/decimaltestdata/class.decTest b/Lib/test/decimaltestdata/class.decTest
index 77a22e3..61ad548 100644
--- a/Lib/test/decimaltestdata/class.decTest
+++ b/Lib/test/decimaltestdata/class.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- [New 2006.11.27]
 
diff --git a/Lib/test/decimaltestdata/compare.decTest b/Lib/test/decimaltestdata/compare.decTest
index 2d5e664..979cc52 100644
--- a/Lib/test/decimaltestdata/compare.decTest
+++ b/Lib/test/decimaltestdata/compare.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Note that we cannot assume add/subtract tests cover paths adequately,
 -- here, because the code might be quite different (comparison cannot
diff --git a/Lib/test/decimaltestdata/comparetotal.decTest b/Lib/test/decimaltestdata/comparetotal.decTest
index 737293f..ef2914f 100644
--- a/Lib/test/decimaltestdata/comparetotal.decTest
+++ b/Lib/test/decimaltestdata/comparetotal.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Note that we cannot assume add/subtract tests cover paths adequately,
 -- here, because the code might be quite different (comparison cannot
diff --git a/Lib/test/decimaltestdata/comparetotmag.decTest b/Lib/test/decimaltestdata/comparetotmag.decTest
index a12e614..4a51d7f 100644
--- a/Lib/test/decimaltestdata/comparetotmag.decTest
+++ b/Lib/test/decimaltestdata/comparetotmag.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Note that it cannot be assumed that add/subtract tests cover paths
 -- for this operation adequately, here, because the code might be
diff --git a/Lib/test/decimaltestdata/copy.decTest b/Lib/test/decimaltestdata/copy.decTest
index 5d4065d..e6edac5 100644
--- a/Lib/test/decimaltestdata/copy.decTest
+++ b/Lib/test/decimaltestdata/copy.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/copyabs.decTest b/Lib/test/decimaltestdata/copyabs.decTest
index 7457552..4479888 100644
--- a/Lib/test/decimaltestdata/copyabs.decTest
+++ b/Lib/test/decimaltestdata/copyabs.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/copynegate.decTest b/Lib/test/decimaltestdata/copynegate.decTest
index 3e502be..7cf124c 100644
--- a/Lib/test/decimaltestdata/copynegate.decTest
+++ b/Lib/test/decimaltestdata/copynegate.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/copysign.decTest b/Lib/test/decimaltestdata/copysign.decTest
index 6b20fda..ed60893 100644
--- a/Lib/test/decimaltestdata/copysign.decTest
+++ b/Lib/test/decimaltestdata/copysign.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/ddAbs.decTest b/Lib/test/decimaltestdata/ddAbs.decTest
index 4da662c..58b7902 100644
--- a/Lib/test/decimaltestdata/ddAbs.decTest
+++ b/Lib/test/decimaltestdata/ddAbs.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/ddAdd.decTest b/Lib/test/decimaltestdata/ddAdd.decTest
index 49d89d4..38d511b 100644
--- a/Lib/test/decimaltestdata/ddAdd.decTest
+++ b/Lib/test/decimaltestdata/ddAdd.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests are for decDoubles only; all arguments are
 -- representable in a decDouble
@@ -1029,6 +1029,16 @@ ddadd71706 add 130E-2   -12E-1  -> 0.10
 ddadd71707 add 130E-2   -1E0    -> 0.30
 ddadd71708 add 1E2      -1E4    -> -9.9E+3
 
+-- query from Vincent Kulandaisamy
+rounding: ceiling
+ddadd71801  add  7.8822773805862E+277    -5.1757503820663E-21 -> 7.882277380586200E+277 Inexact Rounded
+ddadd71802  add  7.882277380586200E+277  12.341               -> 7.882277380586201E+277 Inexact Rounded
+ddadd71803  add  7.882277380586201E+277  2.7270545046613E-31  -> 7.882277380586202E+277 Inexact Rounded
+
+ddadd71811  add                   12.341 -5.1757503820663E-21 -> 12.34100000000000      Inexact Rounded
+ddadd71812  add        12.34100000000000 2.7270545046613E-31  -> 12.34100000000001      Inexact Rounded
+ddadd71813  add        12.34100000000001 7.8822773805862E+277 -> 7.882277380586201E+277 Inexact Rounded
+
 -- Gappy coefficients; check residue handling even with full coefficient gap
 rounding: half_even
 
diff --git a/Lib/test/decimaltestdata/ddAnd.decTest b/Lib/test/decimaltestdata/ddAnd.decTest
index e5fa38d..850da17 100644
--- a/Lib/test/decimaltestdata/ddAnd.decTest
+++ b/Lib/test/decimaltestdata/ddAnd.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/ddBase.decTest b/Lib/test/decimaltestdata/ddBase.decTest
index 431bce1..ddc8185 100644
--- a/Lib/test/decimaltestdata/ddBase.decTest
+++ b/Lib/test/decimaltestdata/ddBase.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This file tests base conversions from string to a decimal number
 -- and back to a string (in Scientific form)
diff --git a/Lib/test/decimaltestdata/ddCanonical.decTest b/Lib/test/decimaltestdata/ddCanonical.decTest
index 308b9ff..4d659b0 100644
--- a/Lib/test/decimaltestdata/ddCanonical.decTest
+++ b/Lib/test/decimaltestdata/ddCanonical.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This file tests that copy operations leave uncanonical operands
 -- unchanged, and vice versa
diff --git a/Lib/test/decimaltestdata/ddClass.decTest b/Lib/test/decimaltestdata/ddClass.decTest
index 0b1d1f3..8a38f4a 100644
--- a/Lib/test/decimaltestdata/ddClass.decTest
+++ b/Lib/test/decimaltestdata/ddClass.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- [New 2006.11.27]
 precision:   16
diff --git a/Lib/test/decimaltestdata/ddCompare.decTest b/Lib/test/decimaltestdata/ddCompare.decTest
index b225d0d..5f6fba5 100644
--- a/Lib/test/decimaltestdata/ddCompare.decTest
+++ b/Lib/test/decimaltestdata/ddCompare.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Note that we cannot assume add/subtract tests cover paths adequately,
 -- here, because the code might be quite different (comparison cannot
diff --git a/Lib/test/decimaltestdata/ddCompareSig.decTest b/Lib/test/decimaltestdata/ddCompareSig.decTest
index 388a656..b4895da 100644
--- a/Lib/test/decimaltestdata/ddCompareSig.decTest
+++ b/Lib/test/decimaltestdata/ddCompareSig.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Note that we cannot assume add/subtract tests cover paths adequately,
 -- here, because the code might be quite different (comparison cannot
diff --git a/Lib/test/decimaltestdata/ddCompareTotal.decTest b/Lib/test/decimaltestdata/ddCompareTotal.decTest
index a8bf477..b86b8df 100644
--- a/Lib/test/decimaltestdata/ddCompareTotal.decTest
+++ b/Lib/test/decimaltestdata/ddCompareTotal.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Note that we cannot assume add/subtract tests cover paths adequately,
 -- here, because the code might be quite different (comparison cannot
diff --git a/Lib/test/decimaltestdata/ddCompareTotalMag.decTest b/Lib/test/decimaltestdata/ddCompareTotalMag.decTest
index b19cf64..e93a749 100644
--- a/Lib/test/decimaltestdata/ddCompareTotalMag.decTest
+++ b/Lib/test/decimaltestdata/ddCompareTotalMag.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Note that we cannot assume add/subtract tests cover paths adequately,
 -- here, because the code might be quite different (comparison cannot
diff --git a/Lib/test/decimaltestdata/ddCopy.decTest b/Lib/test/decimaltestdata/ddCopy.decTest
index 49c6824..9d82db7 100644
--- a/Lib/test/decimaltestdata/ddCopy.decTest
+++ b/Lib/test/decimaltestdata/ddCopy.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decDoubles.
 precision:   16
diff --git a/Lib/test/decimaltestdata/ddCopyAbs.decTest b/Lib/test/decimaltestdata/ddCopyAbs.decTest
index b65f063..c60cc38 100644
--- a/Lib/test/decimaltestdata/ddCopyAbs.decTest
+++ b/Lib/test/decimaltestdata/ddCopyAbs.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decDoubles.
 precision:   16
diff --git a/Lib/test/decimaltestdata/ddCopyNegate.decTest b/Lib/test/decimaltestdata/ddCopyNegate.decTest
index b111c9b..c2c6098 100644
--- a/Lib/test/decimaltestdata/ddCopyNegate.decTest
+++ b/Lib/test/decimaltestdata/ddCopyNegate.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decDoubles.
 precision:   16
diff --git a/Lib/test/decimaltestdata/ddCopySign.decTest b/Lib/test/decimaltestdata/ddCopySign.decTest
index 7c83416..36b060e 100644
--- a/Lib/test/decimaltestdata/ddCopySign.decTest
+++ b/Lib/test/decimaltestdata/ddCopySign.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decDoubles.
 precision:   16
diff --git a/Lib/test/decimaltestdata/ddDivide.decTest b/Lib/test/decimaltestdata/ddDivide.decTest
index 1a953f7..9069894 100644
--- a/Lib/test/decimaltestdata/ddDivide.decTest
+++ b/Lib/test/decimaltestdata/ddDivide.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/ddDivideInt.decTest b/Lib/test/decimaltestdata/ddDivideInt.decTest
index 782fe8d..7116841 100644
--- a/Lib/test/decimaltestdata/ddDivideInt.decTest
+++ b/Lib/test/decimaltestdata/ddDivideInt.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/ddEncode.decTest b/Lib/test/decimaltestdata/ddEncode.decTest
index 16264fc..3fa434c 100644
--- a/Lib/test/decimaltestdata/ddEncode.decTest
+++ b/Lib/test/decimaltestdata/ddEncode.decTest
@@ -18,7 +18,7 @@
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
 -- [Previously called decimal64.decTest]
-version: 2.56
+version: 2.57
 
 -- This set of tests is for the eight-byte concrete representation.
 -- Its characteristics are:
@@ -485,3 +485,6 @@ decd828 apply  #2238000115afb55a ->  4294967294
 decd829 apply  #2238000115afb55b ->  4294967295
 decd830 apply  #2238000115afb57a ->  4294967296
 decd831 apply  #2238000115afb57b ->  4294967297
+
+-- for narrowing
+decd840 apply  #2870000000000000 ->  2.000000000000000E-99
diff --git a/Lib/test/decimaltestdata/ddFMA.decTest b/Lib/test/decimaltestdata/ddFMA.decTest
index 946d680..bc44b6a 100644
--- a/Lib/test/decimaltestdata/ddFMA.decTest
+++ b/Lib/test/decimaltestdata/ddFMA.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
@@ -1663,6 +1663,34 @@ ddfma375087 fma  1  12345678 1E-33                   -> 12345678.00000001 Inexac
 ddfma375088 fma  1  12345678 1E-34                   -> 12345678.00000001 Inexact Rounded
 ddfma375089 fma  1  12345678 1E-35                   -> 12345678.00000001 Inexact Rounded
 
+-- desctructive subtraction (from remainder tests)
+
+-- +++ some of these will be off-by-one remainder vs remainderNear
+
+ddfma4000  fma  -1234567890123454   1.000000000000001    1234567890123456  ->  0.765432109876546
+ddfma4001  fma  -1234567890123443    1.00000000000001    1234567890123456  ->  0.65432109876557
+ddfma4002  fma  -1234567890123332     1.0000000000001    1234567890123456  ->  0.5432109876668
+ddfma4003  fma   -308641972530863   4.000000000000001    1234567890123455  ->  2.691358027469137
+ddfma4004  fma   -308641972530863   4.000000000000001    1234567890123456  ->  3.691358027469137
+ddfma4005  fma   -246913578024696     4.9999999999999    1234567890123456  ->  0.6913578024696
+ddfma4006  fma   -246913578024691    4.99999999999999    1234567890123456  ->  3.46913578024691
+ddfma4007  fma   -246913578024691   4.999999999999999    1234567890123456  ->  1.246913578024691
+ddfma4008  fma   -246913578024691   5.000000000000001    1234567890123456  ->  0.753086421975309
+ddfma4009  fma   -246913578024690    5.00000000000001    1234567890123456  ->  3.53086421975310
+ddfma4010  fma   -246913578024686     5.0000000000001    1234567890123456  ->  1.3086421975314
+ddfma4011  fma  -1234567890123455   1.000000000000001    1234567890123456  ->  -0.234567890123455
+ddfma4012  fma  -1234567890123444    1.00000000000001    1234567890123456  ->  -0.34567890123444
+ddfma4013  fma  -1234567890123333     1.0000000000001    1234567890123456  ->  -0.4567890123333
+ddfma4014  fma   -308641972530864   4.000000000000001    1234567890123455  ->  -1.308641972530864
+ddfma4015  fma   -308641972530864   4.000000000000001    1234567890123456  ->  -0.308641972530864
+ddfma4016  fma   -246913578024696     4.9999999999999    1234567890123456  ->  0.6913578024696
+ddfma4017  fma   -246913578024692    4.99999999999999    1234567890123456  ->  -1.53086421975308
+ddfma4018  fma   -246913578024691   4.999999999999999    1234567890123456  ->  1.246913578024691
+ddfma4019  fma   -246913578024691   5.000000000000001    1234567890123456  ->  0.753086421975309
+ddfma4020  fma   -246913578024691    5.00000000000001    1234567890123456  ->  -1.46913578024691
+ddfma4021  fma   -246913578024686     5.0000000000001    1234567890123456  ->  1.3086421975314
+
+
 -- Null tests
 ddfma39990 fma  1  10  # -> NaN Invalid_operation
 ddfma39991 fma  1   # 10 -> NaN Invalid_operation
diff --git a/Lib/test/decimaltestdata/ddInvert.decTest b/Lib/test/decimaltestdata/ddInvert.decTest
index 2697f59..b4ae744 100644
--- a/Lib/test/decimaltestdata/ddInvert.decTest
+++ b/Lib/test/decimaltestdata/ddInvert.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/ddLogB.decTest b/Lib/test/decimaltestdata/ddLogB.decTest
index f18fd5e..99a3843 100644
--- a/Lib/test/decimaltestdata/ddLogB.decTest
+++ b/Lib/test/decimaltestdata/ddLogB.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/ddMax.decTest b/Lib/test/decimaltestdata/ddMax.decTest
index 5fe600f..515f79a 100644
--- a/Lib/test/decimaltestdata/ddMax.decTest
+++ b/Lib/test/decimaltestdata/ddMax.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/ddMaxMag.decTest b/Lib/test/decimaltestdata/ddMaxMag.decTest
index dbabc99..c43c460 100644
--- a/Lib/test/decimaltestdata/ddMaxMag.decTest
+++ b/Lib/test/decimaltestdata/ddMaxMag.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/ddMin.decTest b/Lib/test/decimaltestdata/ddMin.decTest
index 4ba27f7..c77a71e 100644
--- a/Lib/test/decimaltestdata/ddMin.decTest
+++ b/Lib/test/decimaltestdata/ddMin.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/ddMinMag.decTest b/Lib/test/decimaltestdata/ddMinMag.decTest
index cc5ccec0..9291abc 100644
--- a/Lib/test/decimaltestdata/ddMinMag.decTest
+++ b/Lib/test/decimaltestdata/ddMinMag.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/ddMinus.decTest b/Lib/test/decimaltestdata/ddMinus.decTest
index 9fe196b..07dfa7a 100644
--- a/Lib/test/decimaltestdata/ddMinus.decTest
+++ b/Lib/test/decimaltestdata/ddMinus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decDoubles.
 precision:   16
diff --git a/Lib/test/decimaltestdata/ddMultiply.decTest b/Lib/test/decimaltestdata/ddMultiply.decTest
index 01e0ffe..f506ea2 100644
--- a/Lib/test/decimaltestdata/ddMultiply.decTest
+++ b/Lib/test/decimaltestdata/ddMultiply.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests are for decDoubles only; all arguments are
 -- representable in a decDouble
@@ -454,9 +454,92 @@ ddmul908 multiply  9.999999999999999E-383  0.09999999999999999     -> 1.00000000
 -- hugest
 ddmul909 multiply  9999999999999999 9999999999999999 -> 9.999999999999998E+31 Inexact Rounded
 
+-- power-of-ten edge cases
+ddmul1001 multiply  1      10               -> 10
+ddmul1002 multiply  1      100              -> 100
+ddmul1003 multiply  1      1000             -> 1000
+ddmul1004 multiply  1      10000            -> 10000
+ddmul1005 multiply  1      100000           -> 100000
+ddmul1006 multiply  1      1000000          -> 1000000
+ddmul1007 multiply  1      10000000         -> 10000000
+ddmul1008 multiply  1      100000000        -> 100000000
+ddmul1009 multiply  1      1000000000       -> 1000000000
+ddmul1010 multiply  1      10000000000      -> 10000000000
+ddmul1011 multiply  1      100000000000     -> 100000000000
+ddmul1012 multiply  1      1000000000000    -> 1000000000000
+ddmul1013 multiply  1      10000000000000   -> 10000000000000
+ddmul1014 multiply  1      100000000000000  -> 100000000000000
+ddmul1015 multiply  1      1000000000000000 -> 1000000000000000
+ddmul1021 multiply  10     1                -> 10
+ddmul1022 multiply  10     10               -> 100
+ddmul1023 multiply  10     100              -> 1000
+ddmul1024 multiply  10     1000             -> 10000
+ddmul1025 multiply  10     10000            -> 100000
+ddmul1026 multiply  10     100000           -> 1000000
+ddmul1027 multiply  10     1000000          -> 10000000
+ddmul1028 multiply  10     10000000         -> 100000000
+ddmul1029 multiply  10     100000000        -> 1000000000
+ddmul1030 multiply  10     1000000000       -> 10000000000
+ddmul1031 multiply  10     10000000000      -> 100000000000
+ddmul1032 multiply  10     100000000000     -> 1000000000000
+ddmul1033 multiply  10     1000000000000    -> 10000000000000
+ddmul1034 multiply  10     10000000000000   -> 100000000000000
+ddmul1035 multiply  10     100000000000000  -> 1000000000000000
+ddmul1041 multiply  100    0.1              -> 10.0
+ddmul1042 multiply  100    1                -> 100
+ddmul1043 multiply  100    10               -> 1000
+ddmul1044 multiply  100    100              -> 10000
+ddmul1045 multiply  100    1000             -> 100000
+ddmul1046 multiply  100    10000            -> 1000000
+ddmul1047 multiply  100    100000           -> 10000000
+ddmul1048 multiply  100    1000000          -> 100000000
+ddmul1049 multiply  100    10000000         -> 1000000000
+ddmul1050 multiply  100    100000000        -> 10000000000
+ddmul1051 multiply  100    1000000000       -> 100000000000
+ddmul1052 multiply  100    10000000000      -> 1000000000000
+ddmul1053 multiply  100    100000000000     -> 10000000000000
+ddmul1054 multiply  100    1000000000000    -> 100000000000000
+ddmul1055 multiply  100    10000000000000   -> 1000000000000000
+ddmul1061 multiply  1000   0.01             -> 10.00
+ddmul1062 multiply  1000   0.1              -> 100.0
+ddmul1063 multiply  1000   1                -> 1000
+ddmul1064 multiply  1000   10               -> 10000
+ddmul1065 multiply  1000   100              -> 100000
+ddmul1066 multiply  1000   1000             -> 1000000
+ddmul1067 multiply  1000   10000            -> 10000000
+ddmul1068 multiply  1000   100000           -> 100000000
+ddmul1069 multiply  1000   1000000          -> 1000000000
+ddmul1070 multiply  1000   10000000         -> 10000000000
+ddmul1071 multiply  1000   100000000        -> 100000000000
+ddmul1072 multiply  1000   1000000000       -> 1000000000000
+ddmul1073 multiply  1000   10000000000      -> 10000000000000
+ddmul1074 multiply  1000   100000000000     -> 100000000000000
+ddmul1075 multiply  1000   1000000000000    -> 1000000000000000
+ddmul1081 multiply  10000  0.001            -> 10.000
+ddmul1082 multiply  10000  0.01             -> 100.00
+ddmul1083 multiply  10000  0.1              -> 1000.0
+ddmul1084 multiply  10000  1                -> 10000
+ddmul1085 multiply  10000  10               -> 100000
+ddmul1086 multiply  10000  100              -> 1000000
+ddmul1087 multiply  10000  1000             -> 10000000
+ddmul1088 multiply  10000  10000            -> 100000000
+ddmul1089 multiply  10000  100000           -> 1000000000
+ddmul1090 multiply  10000  1000000          -> 10000000000
+ddmul1091 multiply  10000  10000000         -> 100000000000
+ddmul1092 multiply  10000  100000000        -> 1000000000000
+ddmul1093 multiply  10000  1000000000       -> 10000000000000
+ddmul1094 multiply  10000  10000000000      -> 100000000000000
+ddmul1095 multiply  10000  100000000000     -> 1000000000000000
+
+ddmul1097 multiply  10000   99999999999     ->  999999999990000
+ddmul1098 multiply  10000   99999999999     ->  999999999990000
+
+
+
+
 -- Null tests
-ddmul990 multiply 10  # -> NaN Invalid_operation
-ddmul991 multiply  # 10 -> NaN Invalid_operation
+ddmul9990 multiply 10  # -> NaN Invalid_operation
+ddmul9991 multiply  # 10 -> NaN Invalid_operation
 
 
 
diff --git a/Lib/test/decimaltestdata/ddNextMinus.decTest b/Lib/test/decimaltestdata/ddNextMinus.decTest
index 97c3b09..b9b0de5 100644
--- a/Lib/test/decimaltestdata/ddNextMinus.decTest
+++ b/Lib/test/decimaltestdata/ddNextMinus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decDoubles.
 precision:   16
diff --git a/Lib/test/decimaltestdata/ddNextPlus.decTest b/Lib/test/decimaltestdata/ddNextPlus.decTest
index d01f3c3..2bb2641 100644
--- a/Lib/test/decimaltestdata/ddNextPlus.decTest
+++ b/Lib/test/decimaltestdata/ddNextPlus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decDoubles.
 precision:   16
diff --git a/Lib/test/decimaltestdata/ddNextToward.decTest b/Lib/test/decimaltestdata/ddNextToward.decTest
index e00751b..80e4ac6 100644
--- a/Lib/test/decimaltestdata/ddNextToward.decTest
+++ b/Lib/test/decimaltestdata/ddNextToward.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decDoubles.
 precision:   16
diff --git a/Lib/test/decimaltestdata/ddOr.decTest b/Lib/test/decimaltestdata/ddOr.decTest
index 3a8cdd6..903ced0 100644
--- a/Lib/test/decimaltestdata/ddOr.decTest
+++ b/Lib/test/decimaltestdata/ddOr.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/ddPlus.decTest b/Lib/test/decimaltestdata/ddPlus.decTest
index 962a656..0a2b838 100644
--- a/Lib/test/decimaltestdata/ddPlus.decTest
+++ b/Lib/test/decimaltestdata/ddPlus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decDoubles.
 precision:   16
diff --git a/Lib/test/decimaltestdata/ddQuantize.decTest b/Lib/test/decimaltestdata/ddQuantize.decTest
index 234db92..8cd5287 100644
--- a/Lib/test/decimaltestdata/ddQuantize.decTest
+++ b/Lib/test/decimaltestdata/ddQuantize.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Most of the tests here assume a "regular pattern", where the
 -- sign and coefficient are +1.
diff --git a/Lib/test/decimaltestdata/ddReduce.decTest b/Lib/test/decimaltestdata/ddReduce.decTest
index 71c82e1..545beeb 100644
--- a/Lib/test/decimaltestdata/ddReduce.decTest
+++ b/Lib/test/decimaltestdata/ddReduce.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/ddRemainder.decTest b/Lib/test/decimaltestdata/ddRemainder.decTest
index c7ea762..d805a48 100644
--- a/Lib/test/decimaltestdata/ddRemainder.decTest
+++ b/Lib/test/decimaltestdata/ddRemainder.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
@@ -581,6 +581,19 @@ ddrem1056 remainder  1e-277 -1e+311 ->  1E-277
 ddrem1057 remainder -1e-277  1e+311 -> -1E-277
 ddrem1058 remainder -1e-277 -1e+311 -> -1E-277
 
+-- destructive subtract
+ddrem1101 remainder  1234567890123456  1.000000000000001  ->  0.765432109876546
+ddrem1102 remainder  1234567890123456   1.00000000000001  ->   0.65432109876557
+ddrem1103 remainder  1234567890123456    1.0000000000001  ->    0.5432109876668
+ddrem1104 remainder  1234567890123455  4.000000000000001  ->  2.691358027469137
+ddrem1105 remainder  1234567890123456  4.000000000000001  ->  3.691358027469137
+ddrem1106 remainder  1234567890123456    4.9999999999999  ->    0.6913578024696
+ddrem1107 remainder  1234567890123456   4.99999999999999  ->   3.46913578024691
+ddrem1108 remainder  1234567890123456  4.999999999999999  ->  1.246913578024691
+ddrem1109 remainder  1234567890123456  5.000000000000001  ->  0.753086421975309
+ddrem1110 remainder  1234567890123456   5.00000000000001  ->   3.53086421975310
+ddrem1111 remainder  1234567890123456    5.0000000000001  ->    1.3086421975314
+
 -- Null tests
 ddrem1000 remainder 10  # -> NaN Invalid_operation
 ddrem1001 remainder  # 10 -> NaN Invalid_operation
diff --git a/Lib/test/decimaltestdata/ddRemainderNear.decTest b/Lib/test/decimaltestdata/ddRemainderNear.decTest
index 1f3bafd..dfcd3eb 100644
--- a/Lib/test/decimaltestdata/ddRemainderNear.decTest
+++ b/Lib/test/decimaltestdata/ddRemainderNear.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
@@ -599,6 +599,7 @@ ddrmn969 remaindernear 123e1   9876543210987654 -> 1230
 
 ddrmn980 remaindernear 123e1 1000E299 -> 1.23E+3  -- 123E+1 internally
 
+
 -- overflow and underflow tests [from divide]
 ddrmn1051 remaindernear  1e+277  1e-311 ->  NaN Division_impossible
 ddrmn1052 remaindernear  1e+277 -1e-311 ->  NaN Division_impossible
@@ -609,6 +610,19 @@ ddrmn1056 remaindernear  1e-277 -1e+311 ->  1E-277
 ddrmn1057 remaindernear -1e-277  1e+311 -> -1E-277
 ddrmn1058 remaindernear -1e-277 -1e+311 -> -1E-277
 
+-- destructive subtract
+ddrmn1100 remainderNear  1234567890123456  1.000000000000001  ->  -0.234567890123455
+ddrmn1101 remainderNear  1234567890123456   1.00000000000001  ->   -0.34567890123444
+ddrmn1102 remainderNear  1234567890123456    1.0000000000001  ->    -0.4567890123333
+ddrmn1103 remainderNear  1234567890123455  4.000000000000001  ->  -1.308641972530864
+ddrmn1104 remainderNear  1234567890123456  4.000000000000001  ->  -0.308641972530864
+ddrmn1115 remainderNear  1234567890123456    4.9999999999999  ->     0.6913578024696
+ddrmn1116 remainderNear  1234567890123456   4.99999999999999  ->   -1.53086421975308
+ddrmn1117 remainderNear  1234567890123456  4.999999999999999  ->   1.246913578024691
+ddrmn1118 remainderNear  1234567890123456  5.000000000000001  ->   0.753086421975309
+ddrmn1119 remainderNear  1234567890123456   5.00000000000001  ->   -1.46913578024691
+ddrmn1110 remainderNear  1234567890123456    5.0000000000001  ->     1.3086421975314
+
 -- Null tests
 ddrmn1000 remaindernear 10  # -> NaN Invalid_operation
 ddrmn1001 remaindernear  # 10 -> NaN Invalid_operation
diff --git a/Lib/test/decimaltestdata/ddRotate.decTest b/Lib/test/decimaltestdata/ddRotate.decTest
index 473f2f6..e6294b3 100644
--- a/Lib/test/decimaltestdata/ddRotate.decTest
+++ b/Lib/test/decimaltestdata/ddRotate.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/ddSameQuantum.decTest b/Lib/test/decimaltestdata/ddSameQuantum.decTest
index a396cd1..6f7db15 100644
--- a/Lib/test/decimaltestdata/ddSameQuantum.decTest
+++ b/Lib/test/decimaltestdata/ddSameQuantum.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decDoubles.
 precision:   16
diff --git a/Lib/test/decimaltestdata/ddScaleB.decTest b/Lib/test/decimaltestdata/ddScaleB.decTest
index 4091f86..d0b92b5 100644
--- a/Lib/test/decimaltestdata/ddScaleB.decTest
+++ b/Lib/test/decimaltestdata/ddScaleB.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/ddShift.decTest b/Lib/test/decimaltestdata/ddShift.decTest
index 2cbe06a..f2e80b3 100644
--- a/Lib/test/decimaltestdata/ddShift.decTest
+++ b/Lib/test/decimaltestdata/ddShift.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/ddSubtract.decTest b/Lib/test/decimaltestdata/ddSubtract.decTest
index 89895e9..b10f5e4 100644
--- a/Lib/test/decimaltestdata/ddSubtract.decTest
+++ b/Lib/test/decimaltestdata/ddSubtract.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests are for decDoubles only; all arguments are
 -- representable in a decDouble
diff --git a/Lib/test/decimaltestdata/ddToIntegral.decTest b/Lib/test/decimaltestdata/ddToIntegral.decTest
index 1e3e573..438d347 100644
--- a/Lib/test/decimaltestdata/ddToIntegral.decTest
+++ b/Lib/test/decimaltestdata/ddToIntegral.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests tests the extended specification 'round-to-integral
 -- value-exact' operations (from IEEE 854, later modified in 754r).
diff --git a/Lib/test/decimaltestdata/ddXor.decTest b/Lib/test/decimaltestdata/ddXor.decTest
index 783fc2b..78e9750 100644
--- a/Lib/test/decimaltestdata/ddXor.decTest
+++ b/Lib/test/decimaltestdata/ddXor.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 precision:   16
 maxExponent: 384
diff --git a/Lib/test/decimaltestdata/decDouble.decTest b/Lib/test/decimaltestdata/decDouble.decTest
index d5205b7..bdbf678 100644
--- a/Lib/test/decimaltestdata/decDouble.decTest
+++ b/Lib/test/decimaltestdata/decDouble.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- decDouble tests
 dectest: ddAbs
diff --git a/Lib/test/decimaltestdata/decQuad.decTest b/Lib/test/decimaltestdata/decQuad.decTest
index 4d10069..e9ec663 100644
--- a/Lib/test/decimaltestdata/decQuad.decTest
+++ b/Lib/test/decimaltestdata/decQuad.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- decQuad tests
 dectest: dqAbs
diff --git a/Lib/test/decimaltestdata/decSingle.decTest b/Lib/test/decimaltestdata/decSingle.decTest
index c661fe4..aae9b37 100644
--- a/Lib/test/decimaltestdata/decSingle.decTest
+++ b/Lib/test/decimaltestdata/decSingle.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- decSingle tests
 dectest: dsBase
diff --git a/Lib/test/decimaltestdata/divide.decTest b/Lib/test/decimaltestdata/divide.decTest
index 1cb82b4..ae2bc08 100644
--- a/Lib/test/decimaltestdata/divide.decTest
+++ b/Lib/test/decimaltestdata/divide.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/divideint.decTest b/Lib/test/decimaltestdata/divideint.decTest
index dfa17ca..1c940f5 100644
--- a/Lib/test/decimaltestdata/divideint.decTest
+++ b/Lib/test/decimaltestdata/divideint.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/dqAbs.decTest b/Lib/test/decimaltestdata/dqAbs.decTest
index 01d1f30..df010ac 100644
--- a/Lib/test/decimaltestdata/dqAbs.decTest
+++ b/Lib/test/decimaltestdata/dqAbs.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dqAdd.decTest b/Lib/test/decimaltestdata/dqAdd.decTest
index 72238d3..256bc98 100644
--- a/Lib/test/decimaltestdata/dqAdd.decTest
+++ b/Lib/test/decimaltestdata/dqAdd.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests are for decQuads only; all arguments are
 -- representable in a decQuad
diff --git a/Lib/test/decimaltestdata/dqAnd.decTest b/Lib/test/decimaltestdata/dqAnd.decTest
index be3fb34..e00d44d 100644
--- a/Lib/test/decimaltestdata/dqAnd.decTest
+++ b/Lib/test/decimaltestdata/dqAnd.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dqBase.decTest b/Lib/test/decimaltestdata/dqBase.decTest
index 6cf2f7f..3f2569b 100644
--- a/Lib/test/decimaltestdata/dqBase.decTest
+++ b/Lib/test/decimaltestdata/dqBase.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This file tests base conversions from string to a decimal number
 -- and back to a string (in Scientific form)
diff --git a/Lib/test/decimaltestdata/dqCanonical.decTest b/Lib/test/decimaltestdata/dqCanonical.decTest
index a6b801a..e13c347 100644
--- a/Lib/test/decimaltestdata/dqCanonical.decTest
+++ b/Lib/test/decimaltestdata/dqCanonical.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This file tests that copy operations leave uncanonical operands
 -- unchanged, and vice versa
diff --git a/Lib/test/decimaltestdata/dqClass.decTest b/Lib/test/decimaltestdata/dqClass.decTest
index 185fbfc..a4703f7 100644
--- a/Lib/test/decimaltestdata/dqClass.decTest
+++ b/Lib/test/decimaltestdata/dqClass.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- [New 2006.11.27]
 
diff --git a/Lib/test/decimaltestdata/dqCompare.decTest b/Lib/test/decimaltestdata/dqCompare.decTest
index 8947280..7fccdf1 100644
--- a/Lib/test/decimaltestdata/dqCompare.decTest
+++ b/Lib/test/decimaltestdata/dqCompare.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Note that we cannot assume add/subtract tests cover paths adequately,
 -- here, because the code might be quite different (comparison cannot
diff --git a/Lib/test/decimaltestdata/dqCompareSig.decTest b/Lib/test/decimaltestdata/dqCompareSig.decTest
index 43833ea..36d5e9b 100644
--- a/Lib/test/decimaltestdata/dqCompareSig.decTest
+++ b/Lib/test/decimaltestdata/dqCompareSig.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Note that we cannot assume add/subtract tests cover paths adequately,
 -- here, because the code might be quite different (comparison cannot
diff --git a/Lib/test/decimaltestdata/dqCompareTotal.decTest b/Lib/test/decimaltestdata/dqCompareTotal.decTest
index d4a7c5a..f5cec06 100644
--- a/Lib/test/decimaltestdata/dqCompareTotal.decTest
+++ b/Lib/test/decimaltestdata/dqCompareTotal.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Note that we cannot assume add/subtract tests cover paths adequately,
 -- here, because the code might be quite different (comparison cannot
diff --git a/Lib/test/decimaltestdata/dqCompareTotalMag.decTest b/Lib/test/decimaltestdata/dqCompareTotalMag.decTest
index 9461d6b..76c1089 100644
--- a/Lib/test/decimaltestdata/dqCompareTotalMag.decTest
+++ b/Lib/test/decimaltestdata/dqCompareTotalMag.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Note that we cannot assume add/subtract tests cover paths adequately,
 -- here, because the code might be quite different (comparison cannot
diff --git a/Lib/test/decimaltestdata/dqCopy.decTest b/Lib/test/decimaltestdata/dqCopy.decTest
index b833776..b768801 100644
--- a/Lib/test/decimaltestdata/dqCopy.decTest
+++ b/Lib/test/decimaltestdata/dqCopy.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decQuads.
 extended:    1
diff --git a/Lib/test/decimaltestdata/dqCopyAbs.decTest b/Lib/test/decimaltestdata/dqCopyAbs.decTest
index 91f4a68..427e6dd 100644
--- a/Lib/test/decimaltestdata/dqCopyAbs.decTest
+++ b/Lib/test/decimaltestdata/dqCopyAbs.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decQuads.
 extended:    1
diff --git a/Lib/test/decimaltestdata/dqCopyNegate.decTest b/Lib/test/decimaltestdata/dqCopyNegate.decTest
index 22ac89c..34a6f3c 100644
--- a/Lib/test/decimaltestdata/dqCopyNegate.decTest
+++ b/Lib/test/decimaltestdata/dqCopyNegate.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decQuads.
 extended:    1
diff --git a/Lib/test/decimaltestdata/dqCopySign.decTest b/Lib/test/decimaltestdata/dqCopySign.decTest
index 8f275cd..902c937 100644
--- a/Lib/test/decimaltestdata/dqCopySign.decTest
+++ b/Lib/test/decimaltestdata/dqCopySign.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decQuads.
 extended:    1
diff --git a/Lib/test/decimaltestdata/dqDivide.decTest b/Lib/test/decimaltestdata/dqDivide.decTest
index a84e1d0..1ea6d31 100644
--- a/Lib/test/decimaltestdata/dqDivide.decTest
+++ b/Lib/test/decimaltestdata/dqDivide.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dqDivideInt.decTest b/Lib/test/decimaltestdata/dqDivideInt.decTest
index 953c1e0..b5eec63 100644
--- a/Lib/test/decimaltestdata/dqDivideInt.decTest
+++ b/Lib/test/decimaltestdata/dqDivideInt.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dqEncode.decTest b/Lib/test/decimaltestdata/dqEncode.decTest
index ed3f328..fcb512b 100644
--- a/Lib/test/decimaltestdata/dqEncode.decTest
+++ b/Lib/test/decimaltestdata/dqEncode.decTest
@@ -18,7 +18,7 @@
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
 -- [Previously called decimal128.decTest]
-version: 2.56
+version: 2.57
 
 -- This set of tests is for the sixteen-byte concrete representation.
 -- Its characteristics are:
@@ -468,3 +468,10 @@ decq828 apply  #22080000000000000000000115afb55a ->  4294967294
 decq829 apply  #22080000000000000000000115afb55b ->  4294967295
 decq830 apply  #22080000000000000000000115afb57a ->  4294967296
 decq831 apply  #22080000000000000000000115afb57b ->  4294967297
+
+-- VG testcase
+decq840 apply    #2080000000000000F294000000172636 -> 8.81125000000001349436E-1548
+decq841 apply    #20800000000000008000000000000000 -> 8.000000000000000000E-1550
+decq842 apply    #1EF98490000000010F6E4E0000000000 -> 7.049000000000010795488000000000000E-3097
+decq843 multiply #20800000000000008000000000000000 #2080000000000000F294000000172636 -> #1EF98490000000010F6E4E0000000000 Rounded
+
diff --git a/Lib/test/decimaltestdata/dqFMA.decTest b/Lib/test/decimaltestdata/dqFMA.decTest
index 37d7749..f68fdf9 100644
--- a/Lib/test/decimaltestdata/dqFMA.decTest
+++ b/Lib/test/decimaltestdata/dqFMA.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
@@ -1754,6 +1754,31 @@ dqadd375087 fma  1  12398765432112345678945678 1E-33                   -> 123987
 dqadd375088 fma  1  12398765432112345678945678 1E-34                   -> 12398765432112345678945678.00000001 Inexact Rounded
 dqadd375089 fma  1  12398765432112345678945678 1E-35                   -> 12398765432112345678945678.00000001 Inexact Rounded
 
+-- Destructive subtract (from remainder tests)
+
+-- +++ some of these will be off-by-one remainder vs remainderNear
+
+dqfma4000  fma  -1234567890123456789012345678901233   1.000000000000000000000000000000001    1234567890123456789012345678901234  ->  -0.234567890123456789012345678901233
+dqfma4001  fma  -1234567890123456789012345678901222    1.00000000000000000000000000000001    1234567890123456789012345678901234  ->  -0.34567890123456789012345678901222
+dqfma4002  fma  -1234567890123456789012345678901111     1.0000000000000000000000000000001    1234567890123456789012345678901234  ->  -0.4567890123456789012345678901111
+dqfma4003  fma   -308641972530864197253086419725314   4.000000000000000000000000000000001    1234567890123456789012345678901255  ->  -1.308641972530864197253086419725314
+dqfma4004  fma   -308641972530864197253086419725308   4.000000000000000000000000000000001    1234567890123456789012345678901234  ->  1.691358027469135802746913580274692
+dqfma4005  fma   -246913578024691357802469135780252     4.9999999999999999999999999999999    1234567890123456789012345678901234  ->  -1.3086421975308642197530864219748
+dqfma4006  fma   -246913578024691357802469135780247    4.99999999999999999999999999999999    1234567890123456789012345678901234  ->  1.46913578024691357802469135780247
+dqfma4007  fma   -246913578024691357802469135780247   4.999999999999999999999999999999999    1234567890123456789012345678901234  ->  -0.753086421975308642197530864219753
+dqfma4008  fma   -246913578024691357802469135780247   5.000000000000000000000000000000001    1234567890123456789012345678901234  ->  -1.246913578024691357802469135780247
+dqfma4009  fma   -246913578024691357802469135780246    5.00000000000000000000000000000001    1234567890123456789012345678901234  ->  1.53086421975308642197530864219754
+dqfma4010  fma   -246913578024691357802469135780242     5.0000000000000000000000000000001    1234567890123456789012345678901234  ->  -0.6913578024691357802469135780242
+dqfma4011  fma  -1234567890123456789012345678901232   1.000000000000000000000000000000001    1234567890123456789012345678901234  ->  0.765432109876543210987654321098768
+dqfma4012  fma  -1234567890123456789012345678901221    1.00000000000000000000000000000001    1234567890123456789012345678901234  ->  0.65432109876543210987654321098779
+dqfma4013  fma  -1234567890123456789012345678901110     1.0000000000000000000000000000001    1234567890123456789012345678901234  ->  0.5432109876543210987654321098890
+dqfma4014  fma   -308641972530864197253086419725313   4.000000000000000000000000000000001    1234567890123456789012345678901255  ->  2.691358027469135802746913580274687
+dqfma4015  fma   -308641972530864197253086419725308   4.000000000000000000000000000000001    1234567890123456789012345678901234  ->  1.691358027469135802746913580274692
+dqfma4016  fma   -246913578024691357802469135780251     4.9999999999999999999999999999999    1234567890123456789012345678901234  ->  3.6913578024691357802469135780251
+dqfma4017  fma   -246913578024691357802469135780247    4.99999999999999999999999999999999    1234567890123456789012345678901234  ->  1.46913578024691357802469135780247
+dqfma4018  fma   -246913578024691357802469135780246   4.999999999999999999999999999999999    1234567890123456789012345678901234  ->  4.246913578024691357802469135780246
+dqfma4019  fma   -246913578024691357802469135780241     5.0000000000000000000000000000001    1234567890123456789012345678901234  ->  4.3086421975308642197530864219759
+
 -- Null tests
 dqadd39990 fma  1  10  # -> NaN Invalid_operation
 dqadd39991 fma  1   # 10 -> NaN Invalid_operation
diff --git a/Lib/test/decimaltestdata/dqInvert.decTest b/Lib/test/decimaltestdata/dqInvert.decTest
index 94ba93c..19161c2 100644
--- a/Lib/test/decimaltestdata/dqInvert.decTest
+++ b/Lib/test/decimaltestdata/dqInvert.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dqLogB.decTest b/Lib/test/decimaltestdata/dqLogB.decTest
index baa6d1e..d6cf831 100644
--- a/Lib/test/decimaltestdata/dqLogB.decTest
+++ b/Lib/test/decimaltestdata/dqLogB.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dqMax.decTest b/Lib/test/decimaltestdata/dqMax.decTest
index a00ec1c..a3ba64c 100644
--- a/Lib/test/decimaltestdata/dqMax.decTest
+++ b/Lib/test/decimaltestdata/dqMax.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/dqMaxMag.decTest b/Lib/test/decimaltestdata/dqMaxMag.decTest
index 53eb82c..01b2793 100644
--- a/Lib/test/decimaltestdata/dqMaxMag.decTest
+++ b/Lib/test/decimaltestdata/dqMaxMag.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/dqMin.decTest b/Lib/test/decimaltestdata/dqMin.decTest
index 9e34694..1b82be2 100644
--- a/Lib/test/decimaltestdata/dqMin.decTest
+++ b/Lib/test/decimaltestdata/dqMin.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/dqMinMag.decTest b/Lib/test/decimaltestdata/dqMinMag.decTest
index 733acfd..6d5e4b5 100644
--- a/Lib/test/decimaltestdata/dqMinMag.decTest
+++ b/Lib/test/decimaltestdata/dqMinMag.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/dqMinus.decTest b/Lib/test/decimaltestdata/dqMinus.decTest
index 50ac85a..bf69938 100644
--- a/Lib/test/decimaltestdata/dqMinus.decTest
+++ b/Lib/test/decimaltestdata/dqMinus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decQuads.
 extended:    1
diff --git a/Lib/test/decimaltestdata/dqMultiply.decTest b/Lib/test/decimaltestdata/dqMultiply.decTest
index a6f85e0..c87cc8f 100644
--- a/Lib/test/decimaltestdata/dqMultiply.decTest
+++ b/Lib/test/decimaltestdata/dqMultiply.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests are for decQuads only; all arguments are
 -- representable in a decQuad
@@ -456,18 +456,134 @@ dqmul908 multiply  9.999999999999999999999999999999999E-6143  0.0999999999999999
 
 -- hugest
 dqmul909 multiply 9999999999999999999999999999999999 9999999999999999999999999999999999 -> 9.999999999999999999999999999999998E+67 Inexact Rounded
+-- VG case
+dqmul910 multiply 8.81125000000001349436E-1548 8.000000000000000000E-1550 -> 7.049000000000010795488000000000000E-3097 Rounded
 
 -- Examples from SQL proposal (Krishna Kulkarni)
 precision:   34
 rounding:    half_up
 maxExponent: 6144
 minExponent: -6143
-dqmul1001  multiply 130E-2  120E-2 -> 1.5600
-dqmul1002  multiply 130E-2  12E-1  -> 1.560
-dqmul1003  multiply 130E-2  1E0    -> 1.30
-dqmul1004  multiply 1E2     1E4    -> 1E+6
+dqmul911  multiply 130E-2  120E-2 -> 1.5600
+dqmul912  multiply 130E-2  12E-1  -> 1.560
+dqmul913  multiply 130E-2  1E0    -> 1.30
+dqmul914  multiply 1E2     1E4    -> 1E+6
+
+-- power-of-ten edge cases
+dqmul1001 multiply  1      10               -> 10
+dqmul1002 multiply  1      100              -> 100
+dqmul1003 multiply  1      1000             -> 1000
+dqmul1004 multiply  1      10000            -> 10000
+dqmul1005 multiply  1      100000           -> 100000
+dqmul1006 multiply  1      1000000          -> 1000000
+dqmul1007 multiply  1      10000000         -> 10000000
+dqmul1008 multiply  1      100000000        -> 100000000
+dqmul1009 multiply  1      1000000000       -> 1000000000
+dqmul1010 multiply  1      10000000000      -> 10000000000
+dqmul1011 multiply  1      100000000000     -> 100000000000
+dqmul1012 multiply  1      1000000000000    -> 1000000000000
+dqmul1013 multiply  1      10000000000000   -> 10000000000000
+dqmul1014 multiply  1      100000000000000  -> 100000000000000
+dqmul1015 multiply  1      1000000000000000 -> 1000000000000000
+
+dqmul1016 multiply  1      1000000000000000000 -> 1000000000000000000
+dqmul1017 multiply  1      100000000000000000000000000 -> 100000000000000000000000000
+dqmul1018 multiply  1      1000000000000000000000000000 -> 1000000000000000000000000000
+dqmul1019 multiply  1      10000000000000000000000000000 -> 10000000000000000000000000000
+dqmul1020 multiply  1      1000000000000000000000000000000000 -> 1000000000000000000000000000000000
+
+dqmul1021 multiply  10     1                -> 10
+dqmul1022 multiply  10     10               -> 100
+dqmul1023 multiply  10     100              -> 1000
+dqmul1024 multiply  10     1000             -> 10000
+dqmul1025 multiply  10     10000            -> 100000
+dqmul1026 multiply  10     100000           -> 1000000
+dqmul1027 multiply  10     1000000          -> 10000000
+dqmul1028 multiply  10     10000000         -> 100000000
+dqmul1029 multiply  10     100000000        -> 1000000000
+dqmul1030 multiply  10     1000000000       -> 10000000000
+dqmul1031 multiply  10     10000000000      -> 100000000000
+dqmul1032 multiply  10     100000000000     -> 1000000000000
+dqmul1033 multiply  10     1000000000000    -> 10000000000000
+dqmul1034 multiply  10     10000000000000   -> 100000000000000
+dqmul1035 multiply  10     100000000000000  -> 1000000000000000
+
+dqmul1036 multiply  10     100000000000000000 -> 1000000000000000000
+dqmul1037 multiply  10     10000000000000000000000000 -> 100000000000000000000000000
+dqmul1038 multiply  10     100000000000000000000000000 -> 1000000000000000000000000000
+dqmul1039 multiply  10     1000000000000000000000000000 -> 10000000000000000000000000000
+dqmul1040 multiply  10     100000000000000000000000000000000 -> 1000000000000000000000000000000000
+
+dqmul1041 multiply  100    0.1              -> 10.0
+dqmul1042 multiply  100    1                -> 100
+dqmul1043 multiply  100    10               -> 1000
+dqmul1044 multiply  100    100              -> 10000
+dqmul1045 multiply  100    1000             -> 100000
+dqmul1046 multiply  100    10000            -> 1000000
+dqmul1047 multiply  100    100000           -> 10000000
+dqmul1048 multiply  100    1000000          -> 100000000
+dqmul1049 multiply  100    10000000         -> 1000000000
+dqmul1050 multiply  100    100000000        -> 10000000000
+dqmul1051 multiply  100    1000000000       -> 100000000000
+dqmul1052 multiply  100    10000000000      -> 1000000000000
+dqmul1053 multiply  100    100000000000     -> 10000000000000
+dqmul1054 multiply  100    1000000000000    -> 100000000000000
+dqmul1055 multiply  100    10000000000000   -> 1000000000000000
+
+dqmul1056 multiply  100    10000000000000000 -> 1000000000000000000
+dqmul1057 multiply  100    1000000000000000000000000 -> 100000000000000000000000000
+dqmul1058 multiply  100    10000000000000000000000000 -> 1000000000000000000000000000
+dqmul1059 multiply  100    100000000000000000000000000 -> 10000000000000000000000000000
+dqmul1060 multiply  100    10000000000000000000000000000000 -> 1000000000000000000000000000000000
+
+dqmul1061 multiply  1000   0.01             -> 10.00
+dqmul1062 multiply  1000   0.1              -> 100.0
+dqmul1063 multiply  1000   1                -> 1000
+dqmul1064 multiply  1000   10               -> 10000
+dqmul1065 multiply  1000   100              -> 100000
+dqmul1066 multiply  1000   1000             -> 1000000
+dqmul1067 multiply  1000   10000            -> 10000000
+dqmul1068 multiply  1000   100000           -> 100000000
+dqmul1069 multiply  1000   1000000          -> 1000000000
+dqmul1070 multiply  1000   10000000         -> 10000000000
+dqmul1071 multiply  1000   100000000        -> 100000000000
+dqmul1072 multiply  1000   1000000000       -> 1000000000000
+dqmul1073 multiply  1000   10000000000      -> 10000000000000
+dqmul1074 multiply  1000   100000000000     -> 100000000000000
+dqmul1075 multiply  1000   1000000000000    -> 1000000000000000
+
+dqmul1076 multiply  1000   1000000000000000 -> 1000000000000000000
+dqmul1077 multiply  1000   100000000000000000000000 -> 100000000000000000000000000
+dqmul1078 multiply  1000   1000000000000000000000000 -> 1000000000000000000000000000
+dqmul1079 multiply  1000   10000000000000000000000000 -> 10000000000000000000000000000
+dqmul1080 multiply  1000   1000000000000000000000000000000 -> 1000000000000000000000000000000000
+
+dqmul1081 multiply  10000  0.001            -> 10.000
+dqmul1082 multiply  10000  0.01             -> 100.00
+dqmul1083 multiply  10000  0.1              -> 1000.0
+dqmul1084 multiply  10000  1                -> 10000
+dqmul1085 multiply  10000  10               -> 100000
+dqmul1086 multiply  10000  100              -> 1000000
+dqmul1087 multiply  10000  1000             -> 10000000
+dqmul1088 multiply  10000  10000            -> 100000000
+dqmul1089 multiply  10000  100000           -> 1000000000
+dqmul1090 multiply  10000  1000000          -> 10000000000
+dqmul1091 multiply  10000  10000000         -> 100000000000
+dqmul1092 multiply  10000  100000000        -> 1000000000000
+dqmul1093 multiply  10000  1000000000       -> 10000000000000
+dqmul1094 multiply  10000  10000000000      -> 100000000000000
+dqmul1095 multiply  10000  100000000000     -> 1000000000000000
+
+dqmul1096 multiply  10000  100000000000000 -> 1000000000000000000
+dqmul1097 multiply  10000  10000000000000000000000 -> 100000000000000000000000000
+dqmul1098 multiply  10000  100000000000000000000000 -> 1000000000000000000000000000
+dqmul1099 multiply  10000  1000000000000000000000000 -> 10000000000000000000000000000
+dqmul1100 multiply  10000  100000000000000000000000000000 -> 1000000000000000000000000000000000
+
+dqmul1107 multiply  10000   99999999999     ->  999999999990000
+dqmul1108 multiply  10000   99999999999     ->  999999999990000
 
 -- Null tests
-dqmul990 multiply 10  # -> NaN Invalid_operation
-dqmul991 multiply  # 10 -> NaN Invalid_operation
+dqmul9990 multiply 10  # -> NaN Invalid_operation
+dqmul9991 multiply  # 10 -> NaN Invalid_operation
 
diff --git a/Lib/test/decimaltestdata/dqNextMinus.decTest b/Lib/test/decimaltestdata/dqNextMinus.decTest
index 4880816..e1e3b06 100644
--- a/Lib/test/decimaltestdata/dqNextMinus.decTest
+++ b/Lib/test/decimaltestdata/dqNextMinus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decQuads.
 extended:    1
diff --git a/Lib/test/decimaltestdata/dqNextPlus.decTest b/Lib/test/decimaltestdata/dqNextPlus.decTest
index 8c0ac45..973c8eb 100644
--- a/Lib/test/decimaltestdata/dqNextPlus.decTest
+++ b/Lib/test/decimaltestdata/dqNextPlus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decQuads.
 extended:    1
diff --git a/Lib/test/decimaltestdata/dqNextToward.decTest b/Lib/test/decimaltestdata/dqNextToward.decTest
index e534951..0eb6770 100644
--- a/Lib/test/decimaltestdata/dqNextToward.decTest
+++ b/Lib/test/decimaltestdata/dqNextToward.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decQuads.
 extended:    1
diff --git a/Lib/test/decimaltestdata/dqOr.decTest b/Lib/test/decimaltestdata/dqOr.decTest
index 60470ea..093edcb 100644
--- a/Lib/test/decimaltestdata/dqOr.decTest
+++ b/Lib/test/decimaltestdata/dqOr.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dqPlus.decTest b/Lib/test/decimaltestdata/dqPlus.decTest
index 5dc5a68..ad5b7be 100644
--- a/Lib/test/decimaltestdata/dqPlus.decTest
+++ b/Lib/test/decimaltestdata/dqPlus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decQuads.
 extended:    1
diff --git a/Lib/test/decimaltestdata/dqQuantize.decTest b/Lib/test/decimaltestdata/dqQuantize.decTest
index aa8cf2e..4c3e1ea 100644
--- a/Lib/test/decimaltestdata/dqQuantize.decTest
+++ b/Lib/test/decimaltestdata/dqQuantize.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Most of the tests here assume a "regular pattern", where the
 -- sign and coefficient are +1.
diff --git a/Lib/test/decimaltestdata/dqReduce.decTest b/Lib/test/decimaltestdata/dqReduce.decTest
index 183e9dc..c069040 100644
--- a/Lib/test/decimaltestdata/dqReduce.decTest
+++ b/Lib/test/decimaltestdata/dqReduce.decTest
@@ -18,7 +18,7 @@
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
 
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dqRemainder.decTest b/Lib/test/decimaltestdata/dqRemainder.decTest
index e30fde7..14c358c 100644
--- a/Lib/test/decimaltestdata/dqRemainder.decTest
+++ b/Lib/test/decimaltestdata/dqRemainder.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
@@ -580,6 +580,17 @@ dqrem1058 remainder -1e-277 -1e+311 -> -1E-277
 -- Gyuris example
 dqrem1070 remainder 8.336804418094040989630006819881709E-6143 8.336804418094040989630006819889000E-6143 -> 8.336804418094040989630006819881709E-6143
 
+-- destructive subtract
+dqrem1120  remainder  1234567890123456789012345678901234  1.000000000000000000000000000000001  ->  0.765432109876543210987654321098768
+dqrem1121  remainder  1234567890123456789012345678901234   1.00000000000000000000000000000001  ->   0.65432109876543210987654321098779
+dqrem1122  remainder  1234567890123456789012345678901234    1.0000000000000000000000000000001  ->    0.5432109876543210987654321098890
+dqrem1123  remainder  1234567890123456789012345678901255  4.000000000000000000000000000000001  ->  2.691358027469135802746913580274687
+dqrem1124  remainder  1234567890123456789012345678901234  4.000000000000000000000000000000001  ->  1.691358027469135802746913580274692
+dqrem1125  remainder  1234567890123456789012345678901234    4.9999999999999999999999999999999  ->    3.6913578024691357802469135780251
+dqrem1126  remainder  1234567890123456789012345678901234   4.99999999999999999999999999999999  ->   1.46913578024691357802469135780247
+dqrem1127  remainder  1234567890123456789012345678901234  4.999999999999999999999999999999999  ->  4.246913578024691357802469135780246
+dqrem1128  remainder  1234567890123456789012345678901234    5.0000000000000000000000000000001  ->    4.3086421975308642197530864219759
+
 -- Null tests
 dqrem1000 remainder 10  # -> NaN Invalid_operation
 dqrem1001 remainder  # 10 -> NaN Invalid_operation
diff --git a/Lib/test/decimaltestdata/dqRemainderNear.decTest b/Lib/test/decimaltestdata/dqRemainderNear.decTest
index b62b79f..9074ec4 100644
--- a/Lib/test/decimaltestdata/dqRemainderNear.decTest
+++ b/Lib/test/decimaltestdata/dqRemainderNear.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
@@ -612,6 +612,19 @@ dqrmn1058 remaindernear -1e-277 -1e+311 -> -1E-277
 -- Gyuris example
 dqrmn1070 remainder 8.336804418094040989630006819881709E-6143 8.336804418094040989630006819889000E-6143 -> 8.336804418094040989630006819881709E-6143
 
+-- destructive subtract
+dqrmn1101  remaindernear  1234567890123456789012345678901234  1.000000000000000000000000000000001  ->  -0.234567890123456789012345678901233
+dqrmn1102  remaindernear  1234567890123456789012345678901234   1.00000000000000000000000000000001  ->   -0.34567890123456789012345678901222
+dqrmn1103  remaindernear  1234567890123456789012345678901234    1.0000000000000000000000000000001  ->    -0.4567890123456789012345678901111
+dqrmn1104  remaindernear  1234567890123456789012345678901255  4.000000000000000000000000000000001  ->  -1.308641972530864197253086419725314
+dqrmn1105  remaindernear  1234567890123456789012345678901234  4.000000000000000000000000000000001  ->   1.691358027469135802746913580274692
+dqrmn1106  remaindernear  1234567890123456789012345678901234    4.9999999999999999999999999999999  ->    -1.3086421975308642197530864219748
+dqrmn1107  remaindernear  1234567890123456789012345678901234   4.99999999999999999999999999999999  ->    1.46913578024691357802469135780247
+dqrmn1108  remaindernear  1234567890123456789012345678901234  4.999999999999999999999999999999999  ->  -0.753086421975308642197530864219753
+dqrmn1109  remaindernear  1234567890123456789012345678901234  5.000000000000000000000000000000001  ->  -1.246913578024691357802469135780247
+dqrmn1110  remaindernear  1234567890123456789012345678901234   5.00000000000000000000000000000001  ->    1.53086421975308642197530864219754
+dqrmn1111  remaindernear  1234567890123456789012345678901234    5.0000000000000000000000000000001  ->    -0.6913578024691357802469135780242
+
 -- Null tests
 dqrmn1000 remaindernear 10  # -> NaN Invalid_operation
 dqrmn1001 remaindernear  # 10 -> NaN Invalid_operation
diff --git a/Lib/test/decimaltestdata/dqRotate.decTest b/Lib/test/decimaltestdata/dqRotate.decTest
index f21813c..671cd95 100644
--- a/Lib/test/decimaltestdata/dqRotate.decTest
+++ b/Lib/test/decimaltestdata/dqRotate.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dqSameQuantum.decTest b/Lib/test/decimaltestdata/dqSameQuantum.decTest
index e7264cb..acf7266 100644
--- a/Lib/test/decimaltestdata/dqSameQuantum.decTest
+++ b/Lib/test/decimaltestdata/dqSameQuantum.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- All operands and results are decQuads.
 extended:    1
diff --git a/Lib/test/decimaltestdata/dqScaleB.decTest b/Lib/test/decimaltestdata/dqScaleB.decTest
index 88a3f9d..7355cf0 100644
--- a/Lib/test/decimaltestdata/dqScaleB.decTest
+++ b/Lib/test/decimaltestdata/dqScaleB.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dqShift.decTest b/Lib/test/decimaltestdata/dqShift.decTest
index e728ec5..33df91f 100644
--- a/Lib/test/decimaltestdata/dqShift.decTest
+++ b/Lib/test/decimaltestdata/dqShift.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dqSubtract.decTest b/Lib/test/decimaltestdata/dqSubtract.decTest
index 923742c..d2df184 100644
--- a/Lib/test/decimaltestdata/dqSubtract.decTest
+++ b/Lib/test/decimaltestdata/dqSubtract.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests are for decQuads only; all arguments are
 -- representable in a decQuad
diff --git a/Lib/test/decimaltestdata/dqToIntegral.decTest b/Lib/test/decimaltestdata/dqToIntegral.decTest
index ac50a4a..449dead 100644
--- a/Lib/test/decimaltestdata/dqToIntegral.decTest
+++ b/Lib/test/decimaltestdata/dqToIntegral.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests tests the extended specification 'round-to-integral
 -- value-exact' operations (from IEEE 854, later modified in 754r).
diff --git a/Lib/test/decimaltestdata/dqXor.decTest b/Lib/test/decimaltestdata/dqXor.decTest
index 61bdbe2..d9e9af6 100644
--- a/Lib/test/decimaltestdata/dqXor.decTest
+++ b/Lib/test/decimaltestdata/dqXor.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 clamp:       1
diff --git a/Lib/test/decimaltestdata/dsBase.decTest b/Lib/test/decimaltestdata/dsBase.decTest
index d0632fd..e2fb4ba 100644
--- a/Lib/test/decimaltestdata/dsBase.decTest
+++ b/Lib/test/decimaltestdata/dsBase.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This file tests base conversions from string to a decimal number
 -- and back to a string (in Scientific form)
@@ -1058,4 +1058,5 @@ dsbas1106 toSci +1E-398 ->  0E-101 Inexact Rounded Subnormal Underflow Clamped
 dsbas1107 toSci +1E-383 ->  0E-101 Inexact Rounded Subnormal Underflow Clamped
 dsbas1108 toSci +9.999999999999999E+384 ->  Infinity Overflow Inexact Rounded
 
-
+-- narrowing case
+dsbas1110 toSci 2.000000000000000E-99 -> 2.00E-99 Rounded Subnormal
diff --git a/Lib/test/decimaltestdata/dsEncode.decTest b/Lib/test/decimaltestdata/dsEncode.decTest
index 185ddc7..7e72d4b 100644
--- a/Lib/test/decimaltestdata/dsEncode.decTest
+++ b/Lib/test/decimaltestdata/dsEncode.decTest
@@ -18,7 +18,7 @@
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
 -- [Previously called decimal32.decTest]
-version: 2.56
+version: 2.57
 
 -- This set of tests is for the four-byte concrete representation.
 -- Its characteristics are:
@@ -367,3 +367,6 @@ decs785 apply   #225001ff       -> 999
 decs786 apply   #225002ff       -> 999
 decs787 apply   #225003ff       -> 999
 
+-- narrowing case
+decs790 apply 2.00E-99 -> #00000100 Subnormal
+decs791 apply #00000100 -> 2.00E-99 Subnormal
diff --git a/Lib/test/decimaltestdata/exp.decTest b/Lib/test/decimaltestdata/exp.decTest
index c07ed5a..97256e4 100644
--- a/Lib/test/decimaltestdata/exp.decTest
+++ b/Lib/test/decimaltestdata/exp.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Tests of the exponential funtion.  Currently all testcases here
 -- show results which are correctly rounded (within <= 0.5 ulp).
diff --git a/Lib/test/decimaltestdata/fma.decTest b/Lib/test/decimaltestdata/fma.decTest
index aa4c0ba..d7caa26 100644
--- a/Lib/test/decimaltestdata/fma.decTest
+++ b/Lib/test/decimaltestdata/fma.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/inexact.decTest b/Lib/test/decimaltestdata/inexact.decTest
index b61c85a..896e6c8 100644
--- a/Lib/test/decimaltestdata/inexact.decTest
+++ b/Lib/test/decimaltestdata/inexact.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/invert.decTest b/Lib/test/decimaltestdata/invert.decTest
index 19fdeeb..7bccb1f 100644
--- a/Lib/test/decimaltestdata/invert.decTest
+++ b/Lib/test/decimaltestdata/invert.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/ln.decTest b/Lib/test/decimaltestdata/ln.decTest
index 44ae4d2..16e247e 100644
--- a/Lib/test/decimaltestdata/ln.decTest
+++ b/Lib/test/decimaltestdata/ln.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   16
diff --git a/Lib/test/decimaltestdata/log10.decTest b/Lib/test/decimaltestdata/log10.decTest
index 9841acb..bb033a8 100644
--- a/Lib/test/decimaltestdata/log10.decTest
+++ b/Lib/test/decimaltestdata/log10.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This emphasises the testing of notable cases, as they will often
 -- have unusual paths (especially the 10**n results).
diff --git a/Lib/test/decimaltestdata/logb.decTest b/Lib/test/decimaltestdata/logb.decTest
index 577f7a4..a672206 100644
--- a/Lib/test/decimaltestdata/logb.decTest
+++ b/Lib/test/decimaltestdata/logb.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This emphasises the testing of notable cases, as they will often
 -- have unusual paths (especially the 10**n results).
diff --git a/Lib/test/decimaltestdata/max.decTest b/Lib/test/decimaltestdata/max.decTest
index 88d0b5e..d7a6a94 100644
--- a/Lib/test/decimaltestdata/max.decTest
+++ b/Lib/test/decimaltestdata/max.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/maxmag.decTest b/Lib/test/decimaltestdata/maxmag.decTest
index b14d015..0129766 100644
--- a/Lib/test/decimaltestdata/maxmag.decTest
+++ b/Lib/test/decimaltestdata/maxmag.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/min.decTest b/Lib/test/decimaltestdata/min.decTest
index 345e3eb..b695079 100644
--- a/Lib/test/decimaltestdata/min.decTest
+++ b/Lib/test/decimaltestdata/min.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/minmag.decTest b/Lib/test/decimaltestdata/minmag.decTest
index fa9d927..547ccff 100644
--- a/Lib/test/decimaltestdata/minmag.decTest
+++ b/Lib/test/decimaltestdata/minmag.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- we assume that base comparison is tested in compare.decTest, so
 -- these mainly cover special cases and rounding
diff --git a/Lib/test/decimaltestdata/minus.decTest b/Lib/test/decimaltestdata/minus.decTest
index e9afc3a..f911286 100644
--- a/Lib/test/decimaltestdata/minus.decTest
+++ b/Lib/test/decimaltestdata/minus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests primarily tests the existence of the operator.
 -- Subtraction, rounding, and more overflows are tested elsewhere.
diff --git a/Lib/test/decimaltestdata/multiply.decTest b/Lib/test/decimaltestdata/multiply.decTest
index 71f591a..a6c7ebe 100644
--- a/Lib/test/decimaltestdata/multiply.decTest
+++ b/Lib/test/decimaltestdata/multiply.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/nextminus.decTest b/Lib/test/decimaltestdata/nextminus.decTest
index 200580d..be33158 100644
--- a/Lib/test/decimaltestdata/nextminus.decTest
+++ b/Lib/test/decimaltestdata/nextminus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/nextplus.decTest b/Lib/test/decimaltestdata/nextplus.decTest
index 01815ee..6cee16a 100644
--- a/Lib/test/decimaltestdata/nextplus.decTest
+++ b/Lib/test/decimaltestdata/nextplus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/nexttoward.decTest b/Lib/test/decimaltestdata/nexttoward.decTest
index cb60f57..aa1891a 100644
--- a/Lib/test/decimaltestdata/nexttoward.decTest
+++ b/Lib/test/decimaltestdata/nexttoward.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/or.decTest b/Lib/test/decimaltestdata/or.decTest
index 928939e..ace901b 100644
--- a/Lib/test/decimaltestdata/or.decTest
+++ b/Lib/test/decimaltestdata/or.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/plus.decTest b/Lib/test/decimaltestdata/plus.decTest
index 9af4c0e..1df3dfe 100644
--- a/Lib/test/decimaltestdata/plus.decTest
+++ b/Lib/test/decimaltestdata/plus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests primarily tests the existence of the operator.
 -- Addition and rounding, and most overflows, are tested elsewhere.
diff --git a/Lib/test/decimaltestdata/power.decTest b/Lib/test/decimaltestdata/power.decTest
index 78c1e07..69e8644 100644
--- a/Lib/test/decimaltestdata/power.decTest
+++ b/Lib/test/decimaltestdata/power.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- In addition to the power operator testcases here, see also the file
 -- powersqrt.decTest which includes all the tests from
diff --git a/Lib/test/decimaltestdata/powersqrt.decTest b/Lib/test/decimaltestdata/powersqrt.decTest
index 36e5cbb..6f79f6c 100644
--- a/Lib/test/decimaltestdata/powersqrt.decTest
+++ b/Lib/test/decimaltestdata/powersqrt.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- These testcases are taken from squareroot.decTest but are
 -- evaluated using the power operator.  The differences in results
diff --git a/Lib/test/decimaltestdata/quantize.decTest b/Lib/test/decimaltestdata/quantize.decTest
index a60f1bf..1e5511f 100644
--- a/Lib/test/decimaltestdata/quantize.decTest
+++ b/Lib/test/decimaltestdata/quantize.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- Most of the tests here assume a "regular pattern", where the
 -- sign and coefficient are +1.
diff --git a/Lib/test/decimaltestdata/randomBound32.decTest b/Lib/test/decimaltestdata/randomBound32.decTest
index 7f115ad..0d5881d 100644
--- a/Lib/test/decimaltestdata/randomBound32.decTest
+++ b/Lib/test/decimaltestdata/randomBound32.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.55
+version: 2.57
 
 -- These testcases test calculations at precisions 31, 32, and 33, to
 -- exercise the boundaries around 2**5
diff --git a/Lib/test/decimaltestdata/randoms.decTest b/Lib/test/decimaltestdata/randoms.decTest
index 1529aec..a03b8d5 100644
--- a/Lib/test/decimaltestdata/randoms.decTest
+++ b/Lib/test/decimaltestdata/randoms.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 maxexponent: 999999999
diff --git a/Lib/test/decimaltestdata/reduce.decTest b/Lib/test/decimaltestdata/reduce.decTest
index ddce0c9..189a687 100644
--- a/Lib/test/decimaltestdata/reduce.decTest
+++ b/Lib/test/decimaltestdata/reduce.decTest
@@ -19,7 +19,7 @@
 ------------------------------------------------------------------------
 -- [This used to be called normalize.]
 
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/remainder.decTest b/Lib/test/decimaltestdata/remainder.decTest
index 4c92d0c..1a51c26 100644
--- a/Lib/test/decimaltestdata/remainder.decTest
+++ b/Lib/test/decimaltestdata/remainder.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/remainderNear.decTest b/Lib/test/decimaltestdata/remainderNear.decTest
index cfca91b..fdc1bd8 100644
--- a/Lib/test/decimaltestdata/remainderNear.decTest
+++ b/Lib/test/decimaltestdata/remainderNear.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.55
+version: 2.57
 
 extended:    1
 precision:   9
@@ -413,6 +413,18 @@ rmnx605 remaindernear   7.7 8  -> -0.3
 rmnx606 remaindernear  31.5 3  -> 1.5    -- i=10
 rmnx607 remaindernear  34.5 3  -> -1.5   -- i=11
 
+-- zero signs
+rmnx650 remaindernear  1  1 ->  0
+rmnx651 remaindernear -1  1 -> -0
+rmnx652 remaindernear  1 -1 ->  0
+rmnx653 remaindernear -1 -1 -> -0
+rmnx654 remaindernear  0  1 ->  0
+rmnx655 remaindernear -0  1 -> -0
+rmnx656 remaindernear  0 -1 ->  0
+rmnx657 remaindernear -0 -1 -> -0
+rmnx658 remaindernear  0.00  1  ->  0.00
+rmnx659 remaindernear -0.00  1  -> -0.00
+
 -- Specials
 rmnx680 remaindernear  Inf  -Inf   ->  NaN Invalid_operation
 rmnx681 remaindernear  Inf  -1000  ->  NaN Invalid_operation
diff --git a/Lib/test/decimaltestdata/rescale.decTest b/Lib/test/decimaltestdata/rescale.decTest
index 30597db..882f570 100644
--- a/Lib/test/decimaltestdata/rescale.decTest
+++ b/Lib/test/decimaltestdata/rescale.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- [obsolete]   Quantize.decTest has the improved version
 
diff --git a/Lib/test/decimaltestdata/rotate.decTest b/Lib/test/decimaltestdata/rotate.decTest
index c5ced59..32dbd53 100644
--- a/Lib/test/decimaltestdata/rotate.decTest
+++ b/Lib/test/decimaltestdata/rotate.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/rounding.decTest b/Lib/test/decimaltestdata/rounding.decTest
index d24fbfb..82ca1b0 100644
--- a/Lib/test/decimaltestdata/rounding.decTest
+++ b/Lib/test/decimaltestdata/rounding.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- These tests require that implementations take account of residues in
 -- order to get correct results for some rounding modes.  Rather than
diff --git a/Lib/test/decimaltestdata/samequantum.decTest b/Lib/test/decimaltestdata/samequantum.decTest
index 0b1efff..3fa6cff 100644
--- a/Lib/test/decimaltestdata/samequantum.decTest
+++ b/Lib/test/decimaltestdata/samequantum.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/scaleb.decTest b/Lib/test/decimaltestdata/scaleb.decTest
index 0761dea..e77d938 100644
--- a/Lib/test/decimaltestdata/scaleb.decTest
+++ b/Lib/test/decimaltestdata/scaleb.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/shift.decTest b/Lib/test/decimaltestdata/shift.decTest
index c2a40cc..397024e 100644
--- a/Lib/test/decimaltestdata/shift.decTest
+++ b/Lib/test/decimaltestdata/shift.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/squareroot.decTest b/Lib/test/decimaltestdata/squareroot.decTest
index 2ccff5a..8d7b26e 100644
--- a/Lib/test/decimaltestdata/squareroot.decTest
+++ b/Lib/test/decimaltestdata/squareroot.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/subtract.decTest b/Lib/test/decimaltestdata/subtract.decTest
index 338a09c..a1eca31 100644
--- a/Lib/test/decimaltestdata/subtract.decTest
+++ b/Lib/test/decimaltestdata/subtract.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/decimaltestdata/testall.decTest b/Lib/test/decimaltestdata/testall.decTest
index 1cbc20e..673aaa4 100644
--- a/Lib/test/decimaltestdata/testall.decTest
+++ b/Lib/test/decimaltestdata/testall.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- core tests (using Extended: 1) --------------------------------------
 dectest: base
diff --git a/Lib/test/decimaltestdata/tointegral.decTest b/Lib/test/decimaltestdata/tointegral.decTest
index ad25e6b..340515c 100644
--- a/Lib/test/decimaltestdata/tointegral.decTest
+++ b/Lib/test/decimaltestdata/tointegral.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests tests the extended specification 'round-to-integral
 -- value' operation (from IEEE 854, later modified in 754r).
diff --git a/Lib/test/decimaltestdata/tointegralx.decTest b/Lib/test/decimaltestdata/tointegralx.decTest
index d9bc9f3..381216d 100644
--- a/Lib/test/decimaltestdata/tointegralx.decTest
+++ b/Lib/test/decimaltestdata/tointegralx.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- This set of tests tests the extended specification 'round-to-integral
 -- value' operation (from IEEE 854, later modified in 754r).
diff --git a/Lib/test/decimaltestdata/xor.decTest b/Lib/test/decimaltestdata/xor.decTest
index 2ac1b37..1f3b03b 100644
--- a/Lib/test/decimaltestdata/xor.decTest
+++ b/Lib/test/decimaltestdata/xor.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 extended:    1
 precision:   9
diff --git a/Lib/test/test_decimal.py b/Lib/test/test_decimal.py
index 98b9479..3c64e64 100644
--- a/Lib/test/test_decimal.py
+++ b/Lib/test/test_decimal.py
@@ -464,6 +464,7 @@ class DecimalExplicitConstructionTest(unittest.TestCase):
         self.assertRaises(ValueError, Decimal, (1, (4, 3, 4, None, 1), 2) )
         self.assertRaises(ValueError, Decimal, (1, (4, -3, 4, 9, 1), 2) )
         self.assertRaises(ValueError, Decimal, (1, (4, 10, 4, 9, 1), 2) )
+        self.assertRaises(ValueError, Decimal, (1, (4, 3, 4, 'a', 1), 2) )
 
     def test_explicit_from_Decimal(self):
 
diff --git a/Lib/test/test_doctest.py b/Lib/test/test_doctest.py
index 3b89097..02034b4 100644
--- a/Lib/test/test_doctest.py
+++ b/Lib/test/test_doctest.py
@@ -1916,6 +1916,7 @@ def test_DocFileSuite():
        provided.
 
          >>> import unittest, pkgutil, test
+         >>> added_loader = False
          >>> if not hasattr(test, '__loader__'):
          ...     test.__loader__ = pkgutil.get_loader(test)
          ...     added_loader = True
diff --git a/Lib/test/test_funcattrs.py b/Lib/test/test_funcattrs.py
index bd9caff..b9b2e6e 100644
--- a/Lib/test/test_funcattrs.py
+++ b/Lib/test/test_funcattrs.py
@@ -215,6 +215,17 @@ def test_func_closure():
     verify(c[0].__class__.__name__ == "cell") # don't have a type object handy
     cantset(f, "__closure__", c)
 
+def test_empty_cell():
+    def f(): print(a)
+    try:
+        f.__closure__[0].cell_contents
+    except ValueError:
+        pass
+    else:
+        raise TestFailed("shouldn't be able to read an empty cell")
+
+    a = 12
+
 def test_func_doc():
     def f(): pass
     verify(f.__doc__ is None)
@@ -339,6 +350,7 @@ def test_im_name():
 
 def testmore():
     test_func_closure()
+    test_empty_cell()
     test_func_doc()
     test_func_globals()
     test_func_name()
diff --git a/Lib/trace.py b/Lib/trace.py
index 645517a..f6da026 100644
--- a/Lib/trace.py
+++ b/Lib/trace.py
@@ -282,6 +282,8 @@ class CoverageResults:
             # skip some "files" we don't care about...
             if filename == "<string>":
                 continue
+            if filename.startswith("<doctest "):
+                continue
 
             if filename.endswith((".pyc", ".pyo")):
                 filename = filename[:-1]
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 55ea3b9..018d68c 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -7117,6 +7117,10 @@ all_ins(PyObject *d)
         /* Do not follow links.	 */
         if (ins(d, "O_NOFOLLOW", (long)O_NOFOLLOW)) return -1;
 #endif
+#ifdef O_NOATIME
+	/* Do not update the access time. */
+	if (ins(d, "O_NOATIME", (long)O_NOATIME)) return -1;
+#endif
 
 	/* These come from sysexits.h */
 #ifdef EX_OK
diff --git a/Objects/cellobject.c b/Objects/cellobject.c
index 6794ff3..4984366 100644
--- a/Objects/cellobject.c
+++ b/Objects/cellobject.c
@@ -77,7 +77,12 @@ cell_clear(PyCellObject *op)
 static PyObject *
 cell_get_contents(PyCellObject *op, void *closure)
 {
-	Py_XINCREF(op->ob_ref);
+	if (op->ob_ref == NULL)
+	{
+		PyErr_SetString(PyExc_ValueError, "Cell is empty");
+		return NULL;
+	}
+	Py_INCREF(op->ob_ref);
 	return op->ob_ref;
 }
 
diff --git a/Python/ast.c b/Python/ast.c
index f3a2828..da75975 100644
--- a/Python/ast.c
+++ b/Python/ast.c
@@ -19,6 +19,7 @@
 struct compiling {
     char *c_encoding; /* source encoding */
     PyArena *c_arena; /* arena for allocating memeory */
+    const char *c_filename; /* filename */
 };
 
 static asdl_seq *seq_for_testlist(struct compiling *, const node *);
@@ -226,6 +227,7 @@ PyAST_FromNode(const node *n, PyCompilerFlags *flags, const char *filename,
         c.c_encoding = "utf-8";
     }
     c.c_arena = arena;
+    c.c_filename = filename;
 
     k = 0;
     switch (TYPE(n)) {