Merge pull request #2 from SCons/master

Fast forward master

31 files changed, 907 insertions, 1539 deletions

diff --git a/src/engine/SCons/CacheDir.py b/src/engine/SCons/CacheDir.py
index 704b9a5..10c088d 100644
--- a/src/engine/SCons/CacheDir.py
+++ b/src/engine/SCons/CacheDir.py
@@ -33,6 +33,7 @@ import os
 import stat
 import sys
 
+import SCons
 import SCons.Action
 import SCons.Warnings
 from SCons.Util import PY3
@@ -185,7 +186,7 @@ class CacheDir(object):
             pass
         except OSError:
             msg = "Failed to create cache directory " + path
-            raise SCons.Errors.EnvironmentError(msg)
+            raise SCons.Errors.SConsEnvironmentError(msg)
 
         try:
             with open(config_file, 'x') as config:
@@ -194,14 +195,14 @@ class CacheDir(object):
                     json.dump(self.config, config)
                 except Exception:
                     msg = "Failed to write cache configuration for " + path
-                    raise SCons.Errors.EnvironmentError(msg)
+                    raise SCons.Errors.SConsEnvironmentError(msg)
         except FileExistsError:
             try:
                 with open(config_file) as config:
                     self.config = json.load(config)
             except ValueError:
                 msg = "Failed to read cache configuration for " + path
-                raise SCons.Errors.EnvironmentError(msg)
+                raise SCons.Errors.SConsEnvironmentError(msg)
 
 
     def _readconfig2(self, path):
diff --git a/src/engine/SCons/CacheDirTests.py b/src/engine/SCons/CacheDirTests.py
index ef87746..07c32b4 100644
--- a/src/engine/SCons/CacheDirTests.py
+++ b/src/engine/SCons/CacheDirTests.py
@@ -27,10 +27,13 @@ import os.path
 import shutil
 import sys
 import unittest
+import tempfile
+import stat
 
 from TestCmd import TestCmd
 
 import SCons.CacheDir
+from SCons.Util import PY3
 
 built_it = None
 
@@ -112,6 +115,84 @@ class CacheDirTestCase(BaseTestCase):
         finally:
             SCons.Util.MD5collect = save_collect
 
+class ExceptionTestCase(unittest.TestCase):
+    """Test that the correct exceptions are thrown by CacheDir."""
+
+    # Don't inherit from BaseTestCase, we're by definition trying to
+    # break things so we really want a clean slate for each test.
+    def setUp(self):
+        self.tmpdir = tempfile.mkdtemp()
+        self._CacheDir = SCons.CacheDir.CacheDir(self.tmpdir)
+
+    def tearDown(self):
+        shutil.rmtree(self.tmpdir)
+
+    @unittest.skipIf(sys.platform.startswith("win"), "This fixture will not trigger an OSError on Windows")
+    def test_throws_correct_on_OSError(self):
+        """Test that the correct error is thrown when cache directory cannot be created."""
+        privileged_dir = os.path.join(os.getcwd(), "privileged")
+        try:
+            os.mkdir(privileged_dir)
+            os.chmod(privileged_dir, stat.S_IREAD)
+            cd = SCons.CacheDir.CacheDir(os.path.join(privileged_dir, "cache"))
+            assert False, "Should have raised exception and did not"
+        except SCons.Errors.SConsEnvironmentError as e:
+            assert str(e) == "Failed to create cache directory {}".format(os.path.join(privileged_dir, "cache"))
+        finally:
+            os.chmod(privileged_dir, stat.S_IWRITE | stat.S_IEXEC | stat.S_IREAD)
+            shutil.rmtree(privileged_dir)
+
+
+    def test_throws_correct_when_failed_to_write_configfile(self):
+        class Unserializable:
+            """A class which the JSON should not be able to serialize"""
+
+            def __init__(self, oldconfig):
+                self.something = 1 # Make the object unserializable
+                # Pretend to be the old config just enough
+                self.__dict__["prefix_len"] = oldconfig["prefix_len"]
+
+            def __getitem__(self, name, default=None):
+                if name == "prefix_len":
+                    return self.__dict__["prefix_len"]
+                else:
+                    return None
+
+            def __setitem__(self, name, value):
+                self.__dict__[name] = value
+
+        oldconfig = self._CacheDir.config
+        self._CacheDir.config = Unserializable(oldconfig)
+        # Remove the config file that got created on object creation
+        # so that _readconfig* will try to rewrite it
+        old_config = os.path.join(self._CacheDir.path, "config")
+        os.remove(old_config)
+        
+        try:
+            if PY3:
+                self._CacheDir._readconfig3(self._CacheDir.path)
+            else:
+                self._CacheDir._readconfig2(self._CacheDir.path)
+            assert False, "Should have raised exception and did not"
+        except SCons.Errors.SConsEnvironmentError as e:
+            assert str(e) == "Failed to write cache configuration for {}".format(self._CacheDir.path)
+
+    def test_raise_environment_error_on_invalid_json(self):
+        config_file = os.path.join(self._CacheDir.path, "config")
+        with open(config_file, "r") as cfg:
+            content = cfg.read()
+        # This will make JSON load raise a ValueError
+        content += "{}"
+        with open(config_file, "w") as cfg:
+            cfg.write(content)
+
+        try:
+            # Construct a new cache dir that will try to read the invalid config
+            new_cache_dir = SCons.CacheDir.CacheDir(self._CacheDir.path)
+            assert False, "Should have raised exception and did not"
+        except SCons.Errors.SConsEnvironmentError as e:
+            assert str(e) == "Failed to read cache configuration for {}".format(self._CacheDir.path)
+
 class FileTestCase(BaseTestCase):
     """
     Test calling CacheDir code through Node.FS.File interfaces.
diff --git a/src/engine/SCons/Conftest.py b/src/engine/SCons/Conftest.py
index 1163aa3..c24adf8 100644
--- a/src/engine/SCons/Conftest.py
+++ b/src/engine/SCons/Conftest.py
@@ -290,6 +290,10 @@ char %s();""" % function_name
 #include <assert.h>
 %(hdr)s
 
+#if _MSC_VER && !__INTEL_COMPILER
+    #pragma function(%(name)s)
+#endif
+
 int main(void) {
 #if defined (__stub_%(name)s) || defined (__stub___%(name)s)
   fail fail fail
diff --git a/src/engine/SCons/Environment.py b/src/engine/SCons/Environment.py
index 8d06af7..0e1102e 100644
--- a/src/engine/SCons/Environment.py
+++ b/src/engine/SCons/Environment.py
@@ -46,7 +46,7 @@ import SCons.Builder
 import SCons.Debug
 from SCons.Debug import logInstanceCreation
 import SCons.Defaults
-import SCons.Errors
+from SCons.Errors import UserError, BuildError
 import SCons.Memoize
 import SCons.Node
 import SCons.Node.Alias
@@ -75,11 +75,6 @@ CalculatorArgs = {}
 semi_deepcopy = SCons.Util.semi_deepcopy
 semi_deepcopy_dict = SCons.Util.semi_deepcopy_dict
 
-# Pull UserError into the global name space for the benefit of
-# Environment().SourceSignatures(), which has some import statements
-# which seem to mess up its ability to reference SCons directly.
-UserError = SCons.Errors.UserError
-
 def alias_builder(env, target, source):
     pass
 
@@ -154,7 +149,7 @@ def _set_BUILDERS(env, key, value):
         env._dict[key] = bd
     for k, v in value.items():
         if not SCons.Builder.is_a_Builder(v):
-            raise SCons.Errors.UserError('%s is not a Builder.' % repr(v))
+            raise UserError('%s is not a Builder.' % repr(v))
     bd.update(value)
 
 def _del_SCANNERS(env, key):
@@ -431,7 +426,7 @@ class SubstitutionEnvironment(object):
             # efficient than calling another function or a method.
             if key not in self._dict \
                and not _is_valid_var.match(key):
-                    raise SCons.Errors.UserError("Illegal construction variable `%s'" % key)
+                    raise UserError("Illegal construction variable `%s'" % key)
             self._dict[key] = value
 
     def get(self, key, default=None):
@@ -783,13 +778,14 @@ class SubstitutionEnvironment(object):
                 elif arg in ['-mno-cygwin',
                              '-pthread',
                              '-openmp',
+                             '-fmerge-all-constants',
                              '-fopenmp']:
                     dict['CCFLAGS'].append(arg)
                     dict['LINKFLAGS'].append(arg)
                 elif arg == '-mwindows':
                     dict['LINKFLAGS'].append(arg)
                 elif arg[:5] == '-std=':
-                    if arg[5:].find('++')!=-1:
+                    if '++' in arg[5:]:
                         key='CXXFLAGS'
                     else:
                         key='CFLAGS'
@@ -1492,8 +1488,14 @@ class Base(SubstitutionEnvironment):
 
         self.copy_from_cache = copy_function
 
+
     def Detect(self, progs):
         """Return the first available program in progs.
+
+        :param progs: one or more command names to check for
+        :type progs: str or list
+        :returns str: first name from progs that can be found.
+
         """
         if not SCons.Util.is_List(progs):
             progs = [ progs ]
@@ -1502,7 +1504,17 @@ class Base(SubstitutionEnvironment):
             if path: return prog
         return None
 
+
     def Dictionary(self, *args):
+        """Return construction variables from an environment.
+
+        :param *args: (optional) variable names to look up
+        :returns: if args omitted, the dictionary of all constr. vars.
+            If one arg, the corresponding value is returned.
+            If more than one arg, a list of values is returned.
+        :raises KeyError: if any of *args is not in the construction env.
+
+        """
         if not args:
             return self._dict
         dlist = [self._dict[x] for x in args]
@@ -1510,23 +1522,28 @@ class Base(SubstitutionEnvironment):
             dlist = dlist[0]
         return dlist
 
-    def Dump(self, key = None):
-        """
-        Using the standard Python pretty printer, return the contents of the
-        scons build environment as a string.
 
-        If the key passed in is anything other than None, then that will
-        be used as an index into the build environment dictionary and
-        whatever is found there will be fed into the pretty printer. Note
-        that this key is case sensitive.
+    def Dump(self, key=None):
+        """ Return pretty-printed string of construction variables.
+
+        :param key: if None, format the whole dict of variables.
+            Else look up and format just the value for key.
+
         """
         import pprint
         pp = pprint.PrettyPrinter(indent=2)
         if key:
-            dict = self.Dictionary(key)
+            cvars = self.Dictionary(key)
         else:
-            dict = self.Dictionary()
-        return pp.pformat(dict)
+            cvars = self.Dictionary()
+
+        # TODO: pprint doesn't do a nice job on path-style values
+        # if the paths contain spaces (i.e. Windows), because the
+        # algorithm tries to break lines on spaces, while breaking
+        # on the path-separator would be more "natural". Is there
+        # a better way to format those?
+        return pp.pformat(cvars)
+
 
     def FindIxes(self, paths, prefix, suffix):
         """
@@ -1599,7 +1616,7 @@ class Base(SubstitutionEnvironment):
             for td in tdlist:
                 targets.extend(td[0])
             if len(targets) > 1:
-                raise SCons.Errors.UserError(
+                raise UserError(
                             "More than one dependency target found in `%s':  %s"
                                             % (filename, targets))
         for target, depends in tdlist:
@@ -2038,7 +2055,7 @@ class Base(SubstitutionEnvironment):
         """
         action = self.Action(action, *args, **kw)
         result = action([], [], self)
-        if isinstance(result, SCons.Errors.BuildError):
+        if isinstance(result, BuildError):
             errstr = result.errstr
             if result.filename:
                 errstr = result.filename + ': ' + errstr
@@ -2158,7 +2175,7 @@ class Base(SubstitutionEnvironment):
 
         for side_effect in side_effects:
             if side_effect.multiple_side_effect_has_builder():
-                raise SCons.Errors.UserError("Multiple ways to build the same target were specified for: %s" % str(side_effect))
+                raise UserError("Multiple ways to build the same target were specified for: %s" % str(side_effect))
             side_effect.add_source(targets)
             side_effect.side_effect = 1
             self.Precious(side_effect)
@@ -2176,24 +2193,6 @@ class Base(SubstitutionEnvironment):
             entry.set_src_builder(builder)
         return entries
 
-    def SourceSignatures(self, type):
-        global _warn_source_signatures_deprecated
-        if _warn_source_signatures_deprecated:
-            msg = "The env.SourceSignatures() method is deprecated;\n" + \
-                  "\tconvert your build to use the env.Decider() method instead."
-            SCons.Warnings.warn(SCons.Warnings.DeprecatedSourceSignaturesWarning, msg)
-            _warn_source_signatures_deprecated = False
-        type = self.subst(type)
-        self.src_sig_type = type
-        if type == 'MD5':
-            if not SCons.Util.md5:
-                raise UserError("MD5 signatures are not available in this version of Python.")
-            self.decide_source = self._changed_content
-        elif type == 'timestamp':
-            self.decide_source = self._changed_timestamp_match
-        else:
-            raise UserError("Unknown source signature type '%s'" % type)
-
     def Split(self, arg):
         """This function converts a string or list into a list of strings
         or Nodes.  This makes things easier for users by allowing files to
@@ -2215,28 +2214,6 @@ class Base(SubstitutionEnvironment):
         else:
             return [self.subst(arg)]
 
-    def TargetSignatures(self, type):
-        global _warn_target_signatures_deprecated
-        if _warn_target_signatures_deprecated:
-            msg = "The env.TargetSignatures() method is deprecated;\n" + \
-                  "\tconvert your build to use the env.Decider() method instead."
-            SCons.Warnings.warn(SCons.Warnings.DeprecatedTargetSignaturesWarning, msg)
-            _warn_target_signatures_deprecated = False
-        type = self.subst(type)
-        self.tgt_sig_type = type
-        if type in ('MD5', 'content'):
-            if not SCons.Util.md5:
-                raise UserError("MD5 signatures are not available in this version of Python.")
-            self.decide_target = self._changed_content
-        elif type == 'timestamp':
-            self.decide_target = self._changed_timestamp_match
-        elif type == 'build':
-            self.decide_target = self._changed_build
-        elif type == 'source':
-            self.decide_target = self._changed_source
-        else:
-            raise UserError("Unknown target signature type '%s'"%type)
-
     def Value(self, value, built_value=None):
         """
         """
@@ -2321,7 +2298,7 @@ class OverrideEnvironment(Base):
             return attr.clone(self)
         else:
             return attr
-        
+
     def __setattr__(self, name, value):
         setattr(self.__dict__['__subject'], name, value)
 
@@ -2333,7 +2310,7 @@ class OverrideEnvironment(Base):
             return self.__dict__['__subject'].__getitem__(key)
     def __setitem__(self, key, value):
         if not is_valid_construction_var(key):
-            raise SCons.Errors.UserError("Illegal construction variable `%s'" % key)
+            raise UserError("Illegal construction variable `%s'" % key)
         self.__dict__['overrides'][key] = value
     def __delitem__(self, key):
         try:
diff --git a/src/engine/SCons/Environment.xml b/src/engine/SCons/Environment.xml
index 1b0a04c..829bf12 100644
--- a/src/engine/SCons/Environment.xml
+++ b/src/engine/SCons/Environment.xml
@@ -148,9 +148,9 @@ appending to this list,
 although the more flexible approach
 is to associate scanners
 with a specific Builder.
-See the sections "Builder Objects"
-and "Scanner Objects,"
-below, for more information.
+See the manpage sections "Builder Objects"
+and "Scanner Objects"
+for more information.
 </para>
 </summary>
 </cvar>
@@ -160,7 +160,8 @@ below, for more information.
 <para>
 A reserved variable name
 that may not be set or used in a construction environment.
-(See "Variable Substitution," below.)
+(See the manpage section "Variable Substitution"
+for more information).
 </para>
 </summary>
 </cvar>
@@ -170,7 +171,8 @@ that may not be set or used in a construction environment.
 <para>
 A reserved variable name
 that may not be set or used in a construction environment.
-(See "Variable Substitution," below.)
+(See the manpage section "Variable Substitution"
+for more information).
 </para>
 </summary>
 </cvar>
@@ -180,7 +182,8 @@ that may not be set or used in a construction environment.
 <para>
 A reserved variable name
 that may not be set or used in a construction environment.
-(See "Variable Substitution," below.)
+(See the manpage section "Variable Substitution"
+for more information).
 </para>
 </summary>
 </cvar>
@@ -190,7 +193,8 @@ that may not be set or used in a construction environment.
 <para>
 A reserved variable name
 that may not be set or used in a construction environment.
-(See "Variable Substitution," below.)
+(See the manpage section "Variable Substitution"
+for more information).
 </para>
 </summary>
 </cvar>
@@ -200,7 +204,8 @@ that may not be set or used in a construction environment.
 <para>
 A reserved variable name
 that may not be set or used in a construction environment.
-(See "Variable Substitution," below.)
+(See the manpage section "Variable Substitution"
+for more information).
 </para>
 </summary>
 </cvar>
@@ -210,7 +215,8 @@ that may not be set or used in a construction environment.
 <para>
 A reserved variable name
 that may not be set or used in a construction environment.
-(See "Variable Substitution," below.)
+(See the manpage section "Variable Substitution"
+for more information).
 </para>
 </summary>
 </cvar>
@@ -220,7 +226,8 @@ that may not be set or used in a construction environment.
 <para>
 A reserved variable name
 that may not be set or used in a construction environment.
-(See "Variable Substitution," below.)
+(See the manpage section "Variable Substitution"
+for more information).
 </para>
 </summary>
 </cvar>
@@ -230,7 +237,8 @@ that may not be set or used in a construction environment.
 <para>
 A reserved variable name
 that may not be set or used in a construction environment.
-(See "Variable Substitution," below.)
+(See the manpage section "Variable Substitution"
+for more information).
 </para>
 </summary>
 </cvar>
@@ -255,8 +263,8 @@ that are part of this construction environment.
 Creates an Action object for
 the specified
 <varname>action</varname>.
-See the section "Action Objects,"
-below, for a complete explanation of the arguments and behavior.
+See the manpage section "Action Objects"
+for a complete explanation of the arguments and behavior.
 </para>
 
 <para>
@@ -359,7 +367,8 @@ has been built.
 The specified action(s) may be
 an Action object, or anything that
 can be converted into an Action object
-(see below).
+See the manpage section "Action Objects"
+for a complete explanation.
 </para>
 
 <para>
@@ -386,7 +395,8 @@ is built.
 The specified action(s) may be
 an Action object, or anything that
 can be converted into an Action object
-(see below).
+See the manpage section "Action Objects"
+for a complete explanation.
 </para>
 
 <para>
@@ -512,7 +522,7 @@ Otherwise, the construction variable
 and the value of the keyword argument
 are both coerced to lists,
 and the lists are added together.
-(See also the Prepend method, below.)
+(See also the &Prepend; method).
 </para>
 
 <para>
@@ -634,8 +644,8 @@ or
 Creates a Builder object for
 the specified
 <varname>action</varname>.
-See the section "Builder Objects,"
-below, for a complete explanation of the arguments and behavior.
+See the manpage section "Builder Objects"
+for a complete explanation of the arguments and behavior.
 </para>
 
 <para>
@@ -898,11 +908,15 @@ wx_env = env.Clone(parse_flags='!wx-config --cflags --cxxflags')
 <builder name="Command">
 <summary>
 <para>
-The &b-Command; "Builder" is actually implemented
-as a function that looks like a Builder,
-but actually takes an additional argument of the action
-from which the Builder should be made.
-See the &f-link-Command; function description
+The &b-Command; "Builder" is actually
+a function that looks like a Builder,
+but takes a required third argument, which is the
+action to take to construct the target
+from the source, used for "one-off" builds
+where a full builder is not needed.
+Thus it does not follow the builder
+calling rules described at the start of this section.
+See instead the &f-link-Command; function description
 for the calling syntax and details.
 </para>
 </summary>
@@ -947,7 +961,7 @@ same-named existing construction variables.
 An action can be an external command,
 specified as a string,
 or a callable Python object;
-see "Action Objects," below,
+see the manpage section "Action Objects"
 for more complete information.
 Also note that a string specifying an external command
 may be preceded by an
@@ -971,7 +985,7 @@ env.Command('foo.out', 'foo.in',
 env.Command('bar.out', 'bar.in',
             ["rm -f $TARGET",
              "$BAR_BUILD &lt; $SOURCES &gt; $TARGET"],
-            ENV = {'PATH' : '/usr/local/bin/'})
+            ENV={'PATH': '/usr/local/bin/'})
 
 def rename(env, target, source):
     import os
@@ -979,7 +993,7 @@ def rename(env, target, source):
 
 env.Command('baz.out', 'baz.in',
             ["$BAZ_BUILD &lt; $SOURCES &gt; .tmp",
-	     rename ])
+	     rename])
 </example_commands>
 
 <para>
@@ -988,14 +1002,14 @@ Note that the
 function will usually assume, by default,
 that the specified targets and/or sources are Files,
 if no other part of the configuration
-identifies what type of entry it is.
+identifies what type of entries they are.
 If necessary, you can explicitly specify
 that targets or source nodes should
-be treated as directoriese
+be treated as directories
 by using the
 &f-link-Dir;
 or
-<function>env.Dir</function>()
+<function>env.Dir</function>
 functions.
 </para>
 
@@ -1011,9 +1025,9 @@ env.Command(env.Dir('$DISTDIR')), None, make_distdir)
 </example_commands>
 
 <para>
-(Also note that SCons will usually
+Also note that SCons will usually
 automatically create any directory necessary to hold a target file,
-so you normally don't need to create directories by hand.)
+so you normally don't need to create directories by hand.
 </para>
 </summary>
 </scons_function>
@@ -1029,8 +1043,8 @@ so you normally don't need to create directories by hand.)
 <para>
 Creates a Configure object for integrated
 functionality similar to GNU autoconf.
-See the section "Configure Contexts,"
-below, for a complete explanation of the arguments and behavior.
+See the manpage section "Configure Contexts"
+for a complete explanation of the arguments and behavior.
 </para>
 </summary>
 </scons_function>
@@ -1325,11 +1339,11 @@ env.Depends(bar, installed_lib)
 <summary>
 <para>
 Returns a dictionary object
-containing copies of all of the
-construction variables in the environment.
-If there are any variable names specified,
-only the specified construction
-variables are returned in the dictionary.
+containing the &consvars; in the &consenv;.
+If there are any arguments specified,
+the values of the specified &consvars;
+are returned as a string (if one
+argument) or as a list of strings.
 </para>
 
 <para>
@@ -1337,8 +1351,8 @@ Example:
 </para>
 
 <example_commands>
-dict = env.Dictionary()
-cc_dict = env.Dictionary('CC', 'CCFLAGS', 'CCCOM')
+cvars = env.Dictionary()
+cc_values = env.Dictionary('CC', 'CCFLAGS', 'CCCOM')
 </example_commands>
 </summary>
 </scons_function>
@@ -1375,7 +1389,8 @@ would supply a string as a directory name
 to a Builder method or function.
 Directory Nodes have attributes and methods
 that are useful in many situations;
-see "File and Directory Nodes," below.
+see manpage section "File and Directory Nodes"
+for more information.
 </para>
 </summary>
 </scons_function>
@@ -1458,8 +1473,8 @@ Executes an Action object.
 The specified
 <varname>action</varname>
 may be an Action object
-(see the section "Action Objects,"
-below, for a complete explanation of the arguments and behavior),
+(see manpage section "Action Objects"
+for a complete explanation of the arguments and behavior),
 or it may be a command-line string,
 list of commands,
 or executable Python function,
@@ -1532,7 +1547,8 @@ would supply a string as a file name
 to a Builder method or function.
 File Nodes have attributes and methods
 that are useful in many situations;
-see "File and Directory Nodes," below.
+see manpage section "File and Directory Nodes"
+for more information.
 </para>
 </summary>
 </scons_function>
@@ -2190,7 +2206,7 @@ and the construction variables they affect
 are as specified for the
 &f-link-env-ParseFlags;
 method (which this method calls).
-See that method's description, below,
+See that method's description
 for a table of options and construction variables.
 </para>
 </summary>
@@ -2301,30 +2317,33 @@ and added to the following construction variables:
 </para>
 
 <example_commands>
--arch               CCFLAGS, LINKFLAGS
--D                  CPPDEFINES
--framework          FRAMEWORKS
--frameworkdir=      FRAMEWORKPATH
--include            CCFLAGS
--isysroot           CCFLAGS, LINKFLAGS
--isystem            CCFLAGS
--iquote             CCFLAGS
--idirafter          CCFLAGS
--I                  CPPPATH
--l                  LIBS
--L                  LIBPATH
--mno-cygwin         CCFLAGS, LINKFLAGS
--mwindows           LINKFLAGS
--pthread            CCFLAGS, LINKFLAGS
--std=               CFLAGS
--Wa,                ASFLAGS, CCFLAGS
--Wl,-rpath=         RPATH
--Wl,-R,             RPATH
--Wl,-R              RPATH
--Wl,                LINKFLAGS
--Wp,                CPPFLAGS
--                   CCFLAGS
-+                   CCFLAGS, LINKFLAGS
+-arch                   CCFLAGS, LINKFLAGS
+-D                      CPPDEFINES
+-framework              FRAMEWORKS
+-frameworkdir=          FRAMEWORKPATH
+-fmerge-all-constants   CCFLAGS, LINKFLAGS
+-fopenmp                CCFLAGS, LINKFLAGS
+-include                CCFLAGS
+-isysroot               CCFLAGS, LINKFLAGS
+-isystem                CCFLAGS
+-iquote                 CCFLAGS
+-idirafter              CCFLAGS
+-I                      CPPPATH
+-l                      LIBS
+-L                      LIBPATH
+-mno-cygwin             CCFLAGS, LINKFLAGS
+-mwindows               LINKFLAGS
+-openmp                 CCFLAGS, LINKFLAGS
+-pthread                CCFLAGS, LINKFLAGS
+-std=                   CFLAGS
+-Wa,                    ASFLAGS, CCFLAGS
+-Wl,-rpath=             RPATH
+-Wl,-R,                 RPATH
+-Wl,-R                  RPATH
+-Wl,                    LINKFLAGS
+-Wp,                    CPPFLAGS
+-                       CCFLAGS
++                       CCFLAGS, LINKFLAGS
 </example_commands>
 
 <para>
@@ -2655,8 +2674,8 @@ env.Requires('foo', 'file-that-must-be-built-before-foo')
 Creates a Scanner object for
 the specified
 <varname>function</varname>.
-See the section "Scanner Objects,"
-below, for a complete explanation of the arguments and behavior.
+See manpage section "Scanner Objects"
+for a complete explanation of the arguments and behavior.
 </para>
 </summary>
 </scons_function>
@@ -2968,105 +2987,6 @@ env.SourceCode('no_source.c', None)
 </summary>
 </scons_function>
 
-<scons_function name="SourceSignatures">
-<arguments>
-(type)
-</arguments>
-<summary>
-<para>
-Note:  Although it is not yet officially deprecated,
-use of this function is discouraged.
-See the
-&f-link-Decider;
-function for a more flexible and straightforward way
-to configure SCons' decision-making.
-</para>
-
-<para>
-The
-&f-SourceSignatures;
-function tells
-&scons;
-how to decide if a source file
-(a file that is not built from any other files)
-has changed since the last time it
-was used to build a particular target file.
-Legal values are
-<literal>MD5</literal>
-or
-<literal>timestamp</literal>.
-</para>
-
-<para>
-If the environment method is used,
-the specified type of source signature
-is only used when deciding whether targets
-built with that environment are up-to-date or must be rebuilt.
-If the global function is used,
-the specified type of source signature becomes the default
-used for all decisions
-about whether targets are up-to-date.
-</para>
-
-<para>
-<literal>MD5</literal>
-means
-&scons;
-decides that a source file has changed
-if the MD5 checksum of its contents has changed since
-the last time it was used to rebuild a particular target file.
-</para>
-
-<para>
-<literal>timestamp</literal>
-means
-&scons;
-decides that a source file has changed
-if its timestamp (modification time) has changed since
-the last time it was used to rebuild a particular target file.
-(Note that although this is similar to the behavior of Make,
-by default it will also rebuild if the dependency is
-<emphasis>older</emphasis>
-than the last time it was used to rebuild the target file.)
-</para>
-
-<para>
-There is no different between the two behaviors
-for Python
-&f-Value;
-node objects.
-</para>
-
-<para>
-<literal>MD5</literal>
-signatures take longer to compute,
-but are more accurate than
-<literal>timestamp</literal>
-signatures.
-The default value is
-<literal>MD5</literal>.
-</para>
-
-<para>
-Note that the default
-&f-link-TargetSignatures;
-setting (see below)
-is to use this
-&f-SourceSignatures;
-setting for any target files that are used
-to build other target files.
-Consequently, changing the value of
-&f-SourceSignatures;
-will, by default,
-affect the up-to-date decision for all files in the build
-(or all files built with a specific construction environment
-when
-&f-env-SourceSignatures;
-is used).
-</para>
-</summary>
-</scons_function>
-
 <scons_function name="Split">
 <arguments>
 (arg)
@@ -3210,159 +3130,6 @@ source_nodes = env.subst('$EXPAND_TO_NODELIST',
 </summary>
 </scons_function>
 
-<scons_function name="TargetSignatures">
-<arguments>
-(type)
-</arguments>
-<summary>
-<para>
-Note:  Although it is not yet officially deprecated,
-use of this function is discouraged.
-See the
-&f-link-Decider;
-function for a more flexible and straightforward way
-to configure SCons' decision-making.
-</para>
-
-<para>
-The
-&f-TargetSignatures;
-function tells
-&scons;
-how to decide if a target file
-(a file that
-<emphasis>is</emphasis>
-built from any other files)
-has changed since the last time it
-was used to build some other target file.
-Legal values are
-<literal>"build"</literal>;
-<literal>"content"</literal>
-(or its synonym
-<literal>"MD5"</literal>);
-<literal>"timestamp"</literal>;
-or
-<literal>"source"</literal>.
-</para>
-
-<para>
-If the environment method is used,
-the specified type of target signature is only used
-for targets built with that environment.
-If the global function is used,
-the specified type of signature becomes the default
-used for all target files that
-don't have an explicit target signature type
-specified for their environments.
-</para>
-
-<para>
-<literal>"content"</literal>
-(or its synonym
-<literal>"MD5"</literal>)
-means
-&scons;
-decides that a target file has changed
-if the MD5 checksum of its contents has changed since
-the last time it was used to rebuild some other target file.
-This means
-&scons;
-will open up
-MD5 sum the contents
-of target files after they're built,
-and may decide that it does not need to rebuild
-"downstream" target files if a file was
-rebuilt with exactly the same contents as the last time.
-</para>
-
-<para>
-<literal>"timestamp"</literal>
-means
-&scons;
-decides that a target file has changed
-if its timestamp (modification time) has changed since
-the last time it was used to rebuild some other target file.
-(Note that although this is similar to the behavior of Make,
-by default it will also rebuild if the dependency is
-<emphasis>older</emphasis>
-than the last time it was used to rebuild the target file.)
-</para>
-
-<para>
-<literal>"source"</literal>
-means
-&scons;
-decides that a target file has changed
-as specified by the corresponding
-&f-SourceSignatures;
-setting
-(<literal>"MD5"</literal>
-or
-<literal>"timestamp"</literal>).
-This means that
-&scons;
-will treat all input files to a target the same way,
-regardless of whether they are source files
-or have been built from other files.
-</para>
-
-<para>
-<literal>"build"</literal>
-means
-&scons;
-decides that a target file has changed
-if it has been rebuilt in this invocation
-or if its content or timestamp have changed
-as specified by the corresponding
-&f-SourceSignatures;
-setting.
-This "propagates" the status of a rebuilt file
-so that other "downstream" target files
-will always be rebuilt,
-even if the contents or the timestamp
-have not changed.
-</para>
-
-<para>
-<literal>"build"</literal>
-signatures are fastest because
-<literal>"content"</literal>
-(or
-<literal>"MD5"</literal>)
-signatures take longer to compute,
-but are more accurate than
-<literal>"timestamp"</literal>
-signatures,
-and can prevent unnecessary "downstream" rebuilds
-when a target file is rebuilt to the exact same contents
-as the previous build.
-The
-<literal>"source"</literal>
-setting provides the most consistent behavior
-when other target files may be rebuilt from
-both source and target input files.
-The default value is
-<literal>"source"</literal>.
-</para>
-
-<para>
-Because the default setting is
-<literal>"source"</literal>,
-using
-&f-SourceSignatures;
-is generally preferable to
-&f-TargetSignatures;,
-so that the up-to-date decision
-will be consistent for all files
-(or all files built with a specific construction environment).
-Use of
-&f-TargetSignatures;
-provides specific control for how built target files
-affect their "downstream" dependencies.
-</para>
-</summary>
-</scons_function>
-
 <scons_function name="Tool">
 <arguments>
 (string, [toolpath, **kw])
@@ -3647,30 +3414,51 @@ SConscript(dirs='doc', variant_dir='build/doc', duplicate=0)
 Searches for the specified executable
 <varname>program</varname>,
 returning the full path name to the program
-if it is found,
-and returning None if not.
-Searches the specified
-<varname>path</varname>,
-the value of the calling environment's PATH
-(<literal>env['ENV']['PATH']</literal>),
-or the user's current external PATH
-(<literal>os.environ['PATH']</literal>)
-by default.
+if it is found, else <literal>None</literal>.
+Searches the value of the
+<varname>path</varname> keyword argument,
+or if <literal>None</literal> (the default)
+the value of the calling environment's <envar>PATH</envar>
+(<literal>env['ENV']['PATH']</literal>).
+If <varname>path</varname> is <literal>None</literal> and
+the <literal>env['ENV']['PATH']</literal> key does not exist,
+the user's current external <envar>PATH</envar>
+(<literal>os.environ['PATH']</literal>) is used as fallback.
+</para>
+<para>
 On Windows systems, searches for executable
-programs with any of the file extensions
-listed in the specified
-<varname>pathext</varname>,
-the calling environment's PATHEXT
-(<literal>env['ENV']['PATHEXT']</literal>)
-or the user's current PATHEXT
+programs with any of the file extensions listed in the
+<varname>pathext</varname> keyword argument,
+or if <literal>None</literal> (the default)
+the calling environment's <envar>PATHEXT</envar>
+(<literal>env['ENV']['PATHEXT']</literal>).
+The user's current external <envar>PATHEXT</envar>
 (<literal>os.environ['PATHEXT']</literal>)
-by default.
+is used as a fallback if <varname>pathext</varname> is
+<literal>None</literal>
+and the key <literal>env['ENV']['PATHEXT']</literal>
+does not exist.
+</para>
+<para>
 Will not select any
 path name or names
 in the specified
 <varname>reject</varname>
 list, if any.
 </para>
+<note>
+<para>
+If you would prefer to search
+the user's current external <envar>PATH</envar>
+(<literal>os.environ['PATH']</literal>)
+by default,
+consider using the function <literal>SCons.Util.WhereIs</literal> instead.
+Note that <literal>SCons.Util.WhereIs</literal>
+does not expand environment variables automatically
+(no implicit <literal>env.subst</literal> for its arguments).
+</para>
+</note>
+
 </summary>
 </scons_function>
 
diff --git a/src/engine/SCons/EnvironmentTests.py b/src/engine/SCons/EnvironmentTests.py
index 834cfd1..f016f22 100644
--- a/src/engine/SCons/EnvironmentTests.py
+++ b/src/engine/SCons/EnvironmentTests.py
@@ -797,6 +797,7 @@ sys.exit(0)
             "-F fwd3 " + \
             "-dylib_file foo-dylib " + \
             "-pthread " + \
+            "-fmerge-all-constants " +\
             "-fopenmp " + \
             "-mno-cygwin -mwindows " + \
             "-arch i386 -isysroot /tmp " + \
@@ -811,7 +812,8 @@ sys.exit(0)
         assert d['ASFLAGS'] == ['-as'], d['ASFLAGS']
         assert d['CFLAGS']  == ['-std=c99']
         assert d['CCFLAGS'] == ['-X', '-Wa,-as',
-                                '-pthread', '-fopenmp', '-mno-cygwin',
+                                '-pthread', '-fmerge-all-constants',
+                                '-fopenmp', '-mno-cygwin',
                                 ('-arch', 'i386'), ('-isysroot', '/tmp'),
                                 ('-iquote', '/usr/include/foo1'),
                                 ('-isystem', '/usr/include/foo2'),
@@ -832,7 +834,7 @@ sys.exit(0)
         assert LIBS == ['xxx', 'yyy', 'ascend'], (d['LIBS'], LIBS)
         assert d['LINKFLAGS'] == ['-Wl,-link',
                                   '-dylib_file', 'foo-dylib',
-                                  '-pthread', '-fopenmp',
+                                  '-pthread', '-fmerge-all-constants', '-fopenmp',
                                   '-mno-cygwin', '-mwindows',
                                   ('-arch', 'i386'),
                                   ('-isysroot', '/tmp'),
@@ -2024,6 +2026,7 @@ def generate(env):
                                  "-Ffwd2 " + \
                                  "-F fwd3 " + \
                                  "-pthread " + \
+                                 "-fmerge-all-constants " + \
                                  "-mno-cygwin -mwindows " + \
                                  "-arch i386 -isysroot /tmp " + \
                                  "-iquote /usr/include/foo1 " + \
@@ -2035,7 +2038,7 @@ def generate(env):
             assert save_command == ['fake command'], save_command
             assert env['ASFLAGS'] == ['assembler', '-as'], env['ASFLAGS']
             assert env['CCFLAGS'] == ['', '-X', '-Wa,-as',
-                                      '-pthread', '-mno-cygwin',
+                                      '-pthread', '-fmerge-all-constants', '-mno-cygwin',
                                       ('-arch', 'i386'), ('-isysroot', '/tmp'),
                                       ('-iquote', '/usr/include/foo1'),
                                       ('-isystem', '/usr/include/foo2'),
@@ -2049,6 +2052,7 @@ def generate(env):
             assert env['LIBPATH'] == ['list', '/usr/fax', 'foo'], env['LIBPATH']
             assert env['LIBS'] == ['xxx', 'yyy', env.File('abc')], env['LIBS']
             assert env['LINKFLAGS'] == ['', '-Wl,-link', '-pthread',
+                                        '-fmerge-all-constants',
                                         '-mno-cygwin', '-mwindows',
                                         ('-arch', 'i386'),
                                         ('-isysroot', '/tmp'),
@@ -3280,44 +3284,6 @@ def generate(env):
         s = e.src_builder()
         assert s is None, s
 
-    def test_SourceSignatures(self):
-        """Test the SourceSignatures() method"""
-        import SCons.Errors
-
-        env = self.TestEnvironment(M = 'MD5', T = 'timestamp')
-
-        exc_caught = None
-        try:
-            env.SourceSignatures('invalid_type')
-        except SCons.Errors.UserError:
-            exc_caught = 1
-        assert exc_caught, "did not catch expected UserError"
-
-        env.SourceSignatures('MD5')
-        assert env.src_sig_type == 'MD5', env.src_sig_type
-
-        env.SourceSignatures('$M')
-        assert env.src_sig_type == 'MD5', env.src_sig_type
-
-        env.SourceSignatures('timestamp')
-        assert env.src_sig_type == 'timestamp', env.src_sig_type
-
-        env.SourceSignatures('$T')
-        assert env.src_sig_type == 'timestamp', env.src_sig_type
-
-        try:
-            import SCons.Util
-            save_md5 = SCons.Util.md5
-            SCons.Util.md5 = None
-            try:
-                env.SourceSignatures('MD5')
-            except SCons.Errors.UserError:
-                pass
-            else:
-                self.fail('Did not catch expected UserError')
-        finally:
-            SCons.Util.md5 = save_md5
-
     def test_Split(self):
         """Test the Split() method"""
         env = self.TestEnvironment(FOO = 'fff', BAR = 'bbb')
@@ -3334,56 +3300,6 @@ def generate(env):
         s = env.Split("$FOO$BAR")
         assert s == ["fffbbb"], s
 
-    def test_TargetSignatures(self):
-        """Test the TargetSignatures() method"""
-        import SCons.Errors
-
-        env = self.TestEnvironment(B='build', C='content')
-
-        exc_caught = None
-        try:
-            env.TargetSignatures('invalid_type')
-        except SCons.Errors.UserError:
-            exc_caught = 1
-        assert exc_caught, "did not catch expected UserError"
-        assert not hasattr(env, '_build_signature')
-
-        env.TargetSignatures('build')
-        assert env.tgt_sig_type == 'build', env.tgt_sig_type
-
-        env.TargetSignatures('$B')
-        assert env.tgt_sig_type == 'build', env.tgt_sig_type
-
-        env.TargetSignatures('content')
-        assert env.tgt_sig_type == 'content', env.tgt_sig_type
-
-        env.TargetSignatures('$C')
-        assert env.tgt_sig_type == 'content', env.tgt_sig_type
-
-        env.TargetSignatures('MD5')
-        assert env.tgt_sig_type == 'MD5', env.tgt_sig_type
-
-        env.TargetSignatures('timestamp')
-        assert env.tgt_sig_type == 'timestamp', env.tgt_sig_type
-
-        try:
-            import SCons.Util
-            save_md5 = SCons.Util.md5
-            SCons.Util.md5 = None
-            try:
-                env.TargetSignatures('MD5')
-            except SCons.Errors.UserError:
-                pass
-            else:
-                self.fail('Did not catch expected UserError')
-            try:
-                env.TargetSignatures('content')
-            except SCons.Errors.UserError:
-                pass
-            else:
-                self.fail('Did not catch expected UserError')
-        finally:
-            SCons.Util.md5 = save_md5
 
     def test_Value(self):
         """Test creating a Value() object
@@ -3404,7 +3320,6 @@ def generate(env):
         assert v3.value == 'c', v3.value
 
 
-
     def test_Environment_global_variable(self):
         """Test setting Environment variable to an Environment.Base subclass"""
         class MyEnv(SCons.Environment.Base):
@@ -3746,8 +3661,6 @@ class OverrideEnvironmentTestCase(unittest.TestCase,TestEnvironmentFixture):
     # Environment()
     # FindFile()
     # Scanner()
-    # SourceSignatures()
-    # TargetSignatures()
 
     # It's unlikely Clone() will ever be called this way, so let the
     # other methods test that handling overridden values works.
diff --git a/src/engine/SCons/Node/FS.py b/src/engine/SCons/Node/FS.py
index 33105fb..6b0fe98 100644
--- a/src/engine/SCons/Node/FS.py
+++ b/src/engine/SCons/Node/FS.py
@@ -3436,6 +3436,8 @@ class File(Base):
             Boolean - Indicates if node(File) has changed.
         """
 
+        if node is None:
+            node = self
         # Now get sconsign name -> csig map and then get proper prev_ni if possible
         bi = node.get_stored_info().binfo
         rebuilt = False
diff --git a/src/engine/SCons/Node/FSTests.py b/src/engine/SCons/Node/FSTests.py
index 72eaba7..eddfdf0 100644
--- a/src/engine/SCons/Node/FSTests.py
+++ b/src/engine/SCons/Node/FSTests.py
@@ -2545,11 +2545,10 @@ class FileTestCase(_tempdirTestCase):
 
             def get_ninfo(self):
                 """ mocked to ensure csig will equal the filename"""
-                try:
-                    return self.ninfo
-                except AttributeError:
-                    self.ninfo = FakeNodeInfo(self.name, self.timestamp)
+                if self.ninfo is not None:
                     return self.ninfo
+                self.ninfo = FakeNodeInfo(self.name, self.timestamp)
+                return self.ninfo
 
             def get_csig(self):
                 ninfo = self.get_ninfo()
diff --git a/src/engine/SCons/Node/__init__.py b/src/engine/SCons/Node/__init__.py
index 3073d59..daf79ba 100644
--- a/src/engine/SCons/Node/__init__.py
+++ b/src/engine/SCons/Node/__init__.py
@@ -614,6 +614,7 @@ class Node(object, with_metaclass(NoSlotsPyPy)):
         self._func_rexists = 1
         self._func_get_contents = 0
         self._func_target_from_source = 0
+        self.ninfo = None
 
         self.clear_memoized_values()
 
@@ -1131,11 +1132,10 @@ class Node(object, with_metaclass(NoSlotsPyPy)):
         return ninfo
 
     def get_ninfo(self):
-        try:
-            return self.ninfo
-        except AttributeError:
-            self.ninfo = self.new_ninfo()
+        if self.ninfo is not None:
             return self.ninfo
+        self.ninfo = self.new_ninfo()
+        return self.ninfo
 
     def new_binfo(self):
         binfo = self.BuildInfo()
@@ -1661,10 +1661,7 @@ class Node(object, with_metaclass(NoSlotsPyPy)):
             if k not in old_bkids:
                 lines.append("`%s' is a new dependency\n" % stringify(k))
             else:
-                try:
-                    changed = _decider_map[k.changed_since_last_build](k, self, osig[k])
-                except DeciderNeedsNode as e:
-                    changed = e.decider(self, osig[k], node=self)
+                changed = _decider_map[k.changed_since_last_build](k, self, osig[k])
 
                 if changed:
                     lines.append("`%s' changed\n" % stringify(k))
diff --git a/src/engine/SCons/Script/Main.py b/src/engine/SCons/Script/Main.py
index acc8678..58dbf64 100644
--- a/src/engine/SCons/Script/Main.py
+++ b/src/engine/SCons/Script/Main.py
@@ -75,6 +75,7 @@ print_objects = 0
 print_memoizer = 0
 print_stacktrace = 0
 print_time = 0
+print_action_timestamps = 0
 sconscript_time = 0
 cumulative_command_time = 0
 exit_status = 0   # final exit status, assume success by default
@@ -209,7 +210,11 @@ class BuildTask(SCons.Taskmaster.OutOfDateTask):
             finish_time = time.time()
             last_command_end = finish_time
             cumulative_command_time = cumulative_command_time+finish_time-start_time
+            if print_action_timestamps:
+                sys.stdout.write("Command execution start time: %s: %f seconds\n"%(str(self.node), start_time))
             sys.stdout.write("Command execution time: %s: %f seconds\n"%(str(self.node), finish_time-start_time))
+            if print_action_timestamps:
+                sys.stdout.write("Command execution stop time: %s: %f seconds\n"%(str(self.node), finish_time))
 
     def do_failed(self, status=2):
         _BuildFailures.append(self.exception[1])
@@ -636,7 +641,7 @@ def _SConstruct_exists(dirname='', repositories=[], filelist=None):
     return None
 
 def _set_debug_values(options):
-    global print_memoizer, print_objects, print_stacktrace, print_time
+    global print_memoizer, print_objects, print_stacktrace, print_time, print_action_timestamps
 
     debug_values = options.debug
 
@@ -674,6 +679,9 @@ def _set_debug_values(options):
         options.tree_printers.append(TreePrinter(status=True))
     if "time" in debug_values:
         print_time = 1
+    if "action_timestamps" in debug_values:
+        print_time = 1
+        print_action_timestamps = 1
     if "tree" in debug_values:
         options.tree_printers.append(TreePrinter())
     if "prepare" in debug_values:
diff --git a/src/engine/SCons/Script/SConsOptions.py b/src/engine/SCons/Script/SConsOptions.py
index c45cb01..7b5d523 100644
--- a/src/engine/SCons/Script/SConsOptions.py
+++ b/src/engine/SCons/Script/SConsOptions.py
@@ -584,9 +584,15 @@ def Parser(version):
                   help="Print build actions for files from CacheDir.")
 
     def opt_invalid(group, value, options):
+        """report an invalid option from a group"""
         errmsg  = "`%s' is not a valid %s option type, try:\n" % (value, group)
         return errmsg + "    %s" % ", ".join(options)
 
+    def opt_invalid_rm(group, value, msg):
+        """report an invalid option from a group: recognized but removed"""
+        errmsg  = "`%s' is not a valid %s option type " % (value, group)
+        return errmsg + msg
+
     config_options = ["auto", "force" ,"cache"]
 
     opt_config_help = "Controls Configure subsystem: %s." \
@@ -604,9 +610,11 @@ def Parser(version):
                   help="Search up directory tree for SConstruct,       "
                        "build all Default() targets.")
 
-    deprecated_debug_options = {
+    deprecated_debug_options = {}
+
+    removed_debug_options = {
         "dtree"         : '; please use --tree=derived instead',
-        "nomemoizer"    : ' and has no effect',
+        "nomemoizer"    : '; there is no replacement',
         "stree"         : '; please use --tree=all,status instead',
         "tree"          : '; please use --tree=all instead',
     }
@@ -614,15 +622,16 @@ def Parser(version):
     debug_options = ["count", "duplicate", "explain", "findlibs",
                      "includes", "memoizer", "memory", "objects",
                      "pdb", "prepare", "presub", "stacktrace",
-                     "time"]
+                     "time", "action_timestamps"]
 
     def opt_debug(option, opt, value__, parser,
                   debug_options=debug_options,
-                  deprecated_debug_options=deprecated_debug_options):
+                  deprecated_debug_options=deprecated_debug_options,
+                  removed_debug_options=removed_debug_options):
         for value in value__.split(','):
             if value in debug_options:
                 parser.values.debug.append(value)
-            elif value in list(deprecated_debug_options.keys()):
+            elif value in deprecated_debug_options:
                 parser.values.debug.append(value)
                 try:
                     parser.values.delayed_warnings
@@ -632,6 +641,9 @@ def Parser(version):
                 w = "The --debug=%s option is deprecated%s." % (value, msg)
                 t = (SCons.Warnings.DeprecatedDebugOptionsWarning, w)
                 parser.values.delayed_warnings.append(t)
+            elif value in removed_debug_options:
+                msg = removed_debug_options[value]
+                raise OptionValueError(opt_invalid_rm('debug', value, msg))
             else:
                 raise OptionValueError(opt_invalid('debug', value, debug_options))
 
diff --git a/src/engine/SCons/Script/__init__.py b/src/engine/SCons/Script/__init__.py
index 007eb0d..24af73e 100644
--- a/src/engine/SCons/Script/__init__.py
+++ b/src/engine/SCons/Script/__init__.py
@@ -346,10 +346,8 @@ GlobalDefaultEnvironmentFunctions = [
     'SConsignFile',
     'SideEffect',
     'SourceCode',
-    'SourceSignatures',
     'Split',
     'Tag',
-    'TargetSignatures',
     'Value',
     'VariantDir',
 ]
diff --git a/src/engine/SCons/Subst.py b/src/engine/SCons/Subst.py
index 6f62198..2de64c5 100644
--- a/src/engine/SCons/Subst.py
+++ b/src/engine/SCons/Subst.py
@@ -409,7 +409,7 @@ def scons_subst(strSubst, env, mode=SUBST_RAW, target=None, source=None, gvars={
     handles separating command lines into lists of arguments, so see
     that function if that's what you're looking for.
     """
-    if isinstance(strSubst, str) and strSubst.find('$') < 0:
+    if (isinstance(strSubst, str) and '$' not in strSubst) or isinstance(strSubst, CmdStringHolder):
         return strSubst
 
     class StringSubber(object):
diff --git a/src/engine/SCons/Tool/DCommon.xml b/src/engine/SCons/Tool/DCommon.xml
index f42bea3..8c8c1b5 100644
--- a/src/engine/SCons/Tool/DCommon.xml
+++ b/src/engine/SCons/Tool/DCommon.xml
@@ -23,49 +23,339 @@ See its __doc__ string for a discussion of the format.
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://www.scons.org/dbxsd/v1.0/scons.xsd">
 
+<cvar name="DC">
+<summary>
+<para>
+The D compiler to use.
+</para>
+</summary>
+</cvar>
 
+<cvar name="DCOM">
+<summary>
+<para>
+The command line used to compile a D file to an object file.
+Any options specified in the &cv-link-DFLAGS; construction variable
+is included on this command line.
+</para>
+</summary>
+</cvar>
 
+<cvar name="DDEBUG">
+<summary>
+<para>
+List of debug tags to enable when compiling.
+</para>
+</summary>
+</cvar>
 
+<cvar name="DDEBUGPREFIX">
+<summary>
+<para>
+DDEBUGPREFIX.
+</para>
+</summary>
+</cvar>
 
-    <cvar name="DRPATHPREFIX">
-        <summary>
-            <para>
-                DRPATHPREFIX.
-            </para>
-        </summary>
-    </cvar>
-
-    <cvar name="DRPATHSUFFIX">
-        <summary>
-            <para>
-                DRPATHSUFFIX.
-            </para>
-        </summary>
-    </cvar>
-
-
-    <cvar name="DShLibSonameGenerator">
-        <summary>
-            <para>
-                DShLibSonameGenerator.
-            </para>
-        </summary>
-    </cvar>
-
-    <cvar name="SHDLIBVERSION">
-        <summary>
-            <para>
-                SHDLIBVERSION.
-            </para>
-        </summary>
-    </cvar>
-    <cvar name="SHDLIBVERSIONFLAGS">
-        <summary>
-            <para>
-                SHDLIBVERSIONFLAGS.
-            </para>
-        </summary>
-    </cvar>
+<cvar name="DDEBUGSUFFIX">
+<summary>
+<para>
+DDEBUGSUFFIX.
+</para>
+</summary>
+</cvar>
 
+<cvar name="DFILESUFFIX">
+<summary>
+<para>
+DFILESUFFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DFLAGPREFIX">
+<summary>
+<para>
+DFLAGPREFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DFLAGS">
+<summary>
+<para>
+General options that are passed to the D compiler.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DFLAGSUFFIX">
+<summary>
+<para>
+DFLAGSUFFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DINCSUFFIX">
+<summary>
+<para>
+DLIBFLAGSUFFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DINCPREFIX">
+<summary>
+<para>
+DINCPREFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLIB">
+<summary>
+<para>
+Name of the lib tool to use for D codes.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLIBCOM">
+<summary>
+<para>
+The command line to use when creating libraries.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLIBDIRPREFIX">
+<summary>
+<para>
+DLIBLINKPREFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLIBDIRSUFFIX">
+<summary>
+<para>
+DLIBLINKSUFFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLIBFLAGSUFFIX">
+<summary>
+<para>
+DLIBFLAGSUFFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLIBFLAGPREFIX">
+<summary>
+<para>
+DLIBFLAGPREFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLIBLINKPREFIX">
+<summary>
+<para>
+DLIBLINKPREFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLIBLINKSUFFIX">
+<summary>
+<para>
+DLIBLINKSUFFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLINK">
+<summary>
+<para>
+Name of the linker to use for linking systems including D sources.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLINKCOM">
+<summary>
+<para>
+The command line to use when linking systems including D sources.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLINKFLAGS">
+<summary>
+<para>
+List of linker flags.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLINKFLAGSUFFIX">
+<summary>
+<para>
+DLINKFLAGSUFFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DLINKFLAGPREFIX">
+<summary>
+<para>
+DLINKFLAGPREFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DPATH">
+<summary>
+<para>
+  List of paths to search for import modules.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DRPATHPREFIX">
+<summary>
+<para>
+DRPATHPREFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DRPATHSUFFIX">
+<summary>
+<para>
+DRPATHSUFFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DShLibSonameGenerator">
+<summary>
+<para>
+DShLibSonameGenerator.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DVERPREFIX">
+<summary>
+<para>
+DVERPREFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DVERSIONS">
+<summary>
+<para>
+List of version tags to enable when compiling.
+</para>
+</summary>
+</cvar>
+
+<cvar name="DVERSUFFIX">
+<summary>
+<para>
+DVERSUFFIX.
+</para>
+</summary>
+</cvar>
+
+<cvar name="SHDC">
+<summary>
+<para>
+The name of the compiler to use when compiling D source
+destined to be in a shared objects.
+</para>
+</summary>
+</cvar>
+
+<cvar name="SHDCOM">
+<summary>
+<para>
+The command line to use when compiling code to be part of shared objects.
+</para>
+</summary>
+</cvar>
+
+<cvar name="SHDLIBVERSION">
+<summary>
+<para>
+SHDLIBVERSION.
+</para>
+</summary>
+</cvar>
+
+<cvar name="SHDLIBVERSIONFLAGS">
+<summary>
+<para>
+SHDLIBVERSIONFLAGS.
+</para>
+</summary>
+</cvar>
+
+<cvar name="SHDLINK">
+<summary>
+<para>
+The linker to use when creating shared objects for code bases
+include D sources.
+</para>
+</summary>
+</cvar>
+
+<cvar name="SHDLINKCOM">
+<summary>
+<para>
+The command line to use when generating shared objects.
+</para>
+</summary>
+</cvar>
+
+<cvar name="SHDLINKFLAGS">
+<summary>
+<para>
+The list of flags to use when generating a shared object.
+</para>
+</summary>
+</cvar>
+
+
+<builder name="ProgramAllAtOnce">
+<summary>
+  <para>
+    Builds an executable from D sources without first creating individual
+    objects for each file.
+  </para>
+  <para>
+    D sources can be compiled file-by-file as C and C++ source are, and
+    D is integrated into the &scons; Object and Program builders for
+    this model of build. D codes can though do whole source
+    meta-programming (some of the testing frameworks do this). For this
+    it is imperative that all sources are compiled and linked in a single
+    call to the D compiler. This builder serves that purpose.
+  </para>
+  <example_commands>
+    env.ProgramAllAtOnce('executable', ['mod_a.d, mod_b.d', 'mod_c.d'])
+  </example_commands>
+  <para>
+    This command will compile the modules mod_a, mod_b, and mod_c in a
+    single compilation process without first creating object files for
+    the modules. Some of the D compilers will create executable.o others
+    will not.
+  </para>
+</summary>
+</builder>
 
 </sconsdoc>
diff --git a/src/engine/SCons/Tool/MSCommon/common.py b/src/engine/SCons/Tool/MSCommon/common.py
index c3ba8e5..bbccf61 100644
--- a/src/engine/SCons/Tool/MSCommon/common.py
+++ b/src/engine/SCons/Tool/MSCommon/common.py
@@ -28,28 +28,64 @@ from __future__ import print_function
 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 import copy
+import json
 import os
-import subprocess
 import re
+import subprocess
+import sys
 
 import SCons.Util
 
+# SCONS_MSCOMMON_DEBUG is internal-use so undocumented:
+# set to '-' to print to console, else set to filename to log to
 LOGFILE = os.environ.get('SCONS_MSCOMMON_DEBUG')
 if LOGFILE == '-':
     def debug(message):
         print(message)
 elif LOGFILE:
-    try:
-        import logging
-    except ImportError:
-        debug = lambda message: open(LOGFILE, 'a').write(message + '\n')
-    else:
-        logging.basicConfig(filename=LOGFILE, level=logging.DEBUG)
-        debug = logging.getLogger(name=__name__).debug
+    import logging
+    logging.basicConfig(
+        format='%(relativeCreated)05dms:pid%(process)05d:MSCommon/%(filename)s:%(message)s',
+        filename=LOGFILE,
+        level=logging.DEBUG)
+    debug = logging.getLogger(name=__name__).debug
 else:
     debug = lambda x: None
 
 
+# SCONS_CACHE_MSVC_CONFIG is public, and is documented.
+CONFIG_CACHE = os.environ.get('SCONS_CACHE_MSVC_CONFIG')
+if CONFIG_CACHE in ('1', 'true', 'True'):
+    CONFIG_CACHE = os.path.join(os.path.expanduser('~'), '.scons_msvc_cache')
+
+def read_script_env_cache():
+    """ fetch cached msvc env vars if requested, else return empty dict """
+    envcache = {}
+    if CONFIG_CACHE:
+        try:
+            with open(CONFIG_CACHE, 'r') as f:
+                envcache = json.load(f)
+        #TODO can use more specific FileNotFoundError when py2 dropped
+        except IOError:
+            # don't fail if no cache file, just proceed without it
+            pass
+    return envcache
+
+
+def write_script_env_cache(cache):
+    """ write out cache of msvc env vars if requested """
+    if CONFIG_CACHE:
+        try:
+            with open(CONFIG_CACHE, 'w') as f:
+                json.dump(cache, f, indent=2)
+        except TypeError:
+            # data can't serialize to json, don't leave partial file
+            os.remove(CONFIG_CACHE)
+        except IOError:
+            # can't write the file, just skip
+            pass
+
+
 _is_win64 = None
 
 def is_win64():
@@ -199,7 +235,6 @@ def get_output(vcbat, args = None, env = None):
     if stderr:
         # TODO: find something better to do with stderr;
         # this at least prevents errors from getting swallowed.
-        import sys
         sys.stderr.write(stderr)
     if popen.wait() != 0:
         raise IOError(stderr.decode("mbcs"))
@@ -207,14 +242,15 @@ def get_output(vcbat, args = None, env = None):
     output = stdout.decode("mbcs")
     return output
 
-def parse_output(output, keep=("INCLUDE", "LIB", "LIBPATH", "PATH", 'VSCMD_ARG_app_plat')):
+KEEPLIST = ("INCLUDE", "LIB", "LIBPATH", "PATH", 'VSCMD_ARG_app_plat')
+def parse_output(output, keep=KEEPLIST):
     """
     Parse output from running visual c++/studios vcvarsall.bat and running set
     To capture the values listed in keep
     """
 
     # dkeep is a dict associating key: path_list, where key is one item from
-    # keep, and pat_list the associated list of paths
+    # keep, and path_list the associated list of paths
     dkeep = dict([(i, []) for i in keep])
 
     # rdk will  keep the regex to match the .bat file output line starts
diff --git a/src/engine/SCons/Tool/MSCommon/sdk.py b/src/engine/SCons/Tool/MSCommon/sdk.py
index ad57865..281c1e3 100644
--- a/src/engine/SCons/Tool/MSCommon/sdk.py
+++ b/src/engine/SCons/Tool/MSCommon/sdk.py
@@ -118,11 +118,11 @@ class SDKDefinition(object):
         if (host_arch != target_arch):
             arch_string='%s_%s'%(host_arch,target_arch)
 
-        debug("sdk.py: get_sdk_vc_script():arch_string:%s host_arch:%s target_arch:%s"%(arch_string,
+        debug("get_sdk_vc_script():arch_string:%s host_arch:%s target_arch:%s"%(arch_string,
                                                            host_arch,
                                                            target_arch))
         file=self.vc_setup_scripts.get(arch_string,None)
-        debug("sdk.py: get_sdk_vc_script():file:%s"%file)
+        debug("get_sdk_vc_script():file:%s"%file)
         return file
 
 class WindowsSDK(SDKDefinition):
@@ -286,14 +286,14 @@ InstalledSDKMap = None
 def get_installed_sdks():
     global InstalledSDKList
     global InstalledSDKMap
-    debug('sdk.py:get_installed_sdks()')
+    debug('get_installed_sdks()')
     if InstalledSDKList is None:
         InstalledSDKList = []
         InstalledSDKMap = {}
         for sdk in SupportedSDKList:
-            debug('MSCommon/sdk.py: trying to find SDK %s' % sdk.version)
+            debug('trying to find SDK %s' % sdk.version)
             if sdk.get_sdk_dir():
-                debug('MSCommon/sdk.py:found SDK %s' % sdk.version)
+                debug('found SDK %s' % sdk.version)
                 InstalledSDKList.append(sdk)
                 InstalledSDKMap[sdk.version] = sdk
     return InstalledSDKList
@@ -346,13 +346,13 @@ def get_default_sdk():
     return InstalledSDKList[0]
 
 def mssdk_setup_env(env):
-    debug('sdk.py:mssdk_setup_env()')
+    debug('mssdk_setup_env()')
     if 'MSSDK_DIR' in env:
         sdk_dir = env['MSSDK_DIR']
         if sdk_dir is None:
             return
         sdk_dir = env.subst(sdk_dir)
-        debug('sdk.py:mssdk_setup_env: Using MSSDK_DIR:{}'.format(sdk_dir))
+        debug('mssdk_setup_env: Using MSSDK_DIR:{}'.format(sdk_dir))
     elif 'MSSDK_VERSION' in env:
         sdk_version = env['MSSDK_VERSION']
         if sdk_version is None:
@@ -364,22 +364,22 @@ def mssdk_setup_env(env):
             msg = "SDK version %s is not installed" % sdk_version
             raise SCons.Errors.UserError(msg)
         sdk_dir = mssdk.get_sdk_dir()
-        debug('sdk.py:mssdk_setup_env: Using MSSDK_VERSION:%s'%sdk_dir)
+        debug('mssdk_setup_env: Using MSSDK_VERSION:%s'%sdk_dir)
     elif 'MSVS_VERSION' in env:
         msvs_version = env['MSVS_VERSION']
-        debug('sdk.py:mssdk_setup_env:Getting MSVS_VERSION from env:%s'%msvs_version)
+        debug('mssdk_setup_env:Getting MSVS_VERSION from env:%s'%msvs_version)
         if msvs_version is None:
-            debug('sdk.py:mssdk_setup_env thinks msvs_version is None')
+            debug('mssdk_setup_env thinks msvs_version is None')
             return
         msvs_version = env.subst(msvs_version)
         from . import vs
         msvs = vs.get_vs_by_version(msvs_version)
-        debug('sdk.py:mssdk_setup_env:msvs is :%s'%msvs)
+        debug('mssdk_setup_env:msvs is :%s'%msvs)
         if not msvs:
-            debug('sdk.py:mssdk_setup_env: no VS version detected, bailingout:%s'%msvs)
+            debug('mssdk_setup_env: no VS version detected, bailingout:%s'%msvs)
             return
         sdk_version = msvs.sdk_version
-        debug('sdk.py:msvs.sdk_version is %s'%sdk_version)
+        debug('msvs.sdk_version is %s'%sdk_version)
         if not sdk_version:
             return
         mssdk = get_sdk_by_version(sdk_version)
@@ -388,13 +388,13 @@ def mssdk_setup_env(env):
             if not mssdk:
                 return
         sdk_dir = mssdk.get_sdk_dir()
-        debug('sdk.py:mssdk_setup_env: Using MSVS_VERSION:%s'%sdk_dir)
+        debug('mssdk_setup_env: Using MSVS_VERSION:%s'%sdk_dir)
     else:
         mssdk = get_default_sdk()
         if not mssdk:
             return
         sdk_dir = mssdk.get_sdk_dir()
-        debug('sdk.py:mssdk_setup_env: not using any env values. sdk_dir:%s'%sdk_dir)
+        debug('mssdk_setup_env: not using any env values. sdk_dir:%s'%sdk_dir)
 
     set_sdk_by_directory(env, sdk_dir)
 
diff --git a/src/engine/SCons/Tool/MSCommon/vc.py b/src/engine/SCons/Tool/MSCommon/vc.py
index 0e4ef15..4f6048d 100644
--- a/src/engine/SCons/Tool/MSCommon/vc.py
+++ b/src/engine/SCons/Tool/MSCommon/vc.py
@@ -40,7 +40,10 @@ import SCons.Util
 import subprocess
 import os
 import platform
+import sys
 from string import digits as string_digits
+if sys.version_info[0] == 2:
+    import collections
 
 import SCons.Warnings
 from SCons.Tool import find_program_path
@@ -152,20 +155,15 @@ def get_msvc_version_numeric(msvc_version):
     return ''.join([x for  x in msvc_version if x in string_digits + '.'])
 
 def get_host_target(env):
-    debug('vc.py:get_host_target()')
+    debug('get_host_target()')
 
     host_platform = env.get('HOST_ARCH')
     if not host_platform:
         host_platform = platform.machine()
-        # TODO(2.5):  the native Python platform.machine() function returns
-        # '' on all Python versions before 2.6, after which it also uses
-        # PROCESSOR_ARCHITECTURE.
-        if not host_platform:
-            host_platform = os.environ.get('PROCESSOR_ARCHITECTURE', '')
 
     # Retain user requested TARGET_ARCH
     req_target_platform = env.get('TARGET_ARCH')
-    debug('vc.py:get_host_target() req_target_platform:%s'%req_target_platform)
+    debug('get_host_target() req_target_platform:%s'%req_target_platform)
 
     if  req_target_platform:
         # If user requested a specific platform then only try that one.
@@ -403,7 +401,7 @@ def find_batch_file(env,msvc_version,host_arch,target_arch):
     if pdir is None:
         raise NoVersionFound("No version of Visual Studio found")
 
-    debug('vc.py: find_batch_file() in {}'.format(pdir))
+    debug('find_batch_file() in {}'.format(pdir))
 
     # filter out e.g. "Exp" from the version name
     msvc_ver_numeric = get_msvc_version_numeric(msvc_version)
@@ -423,17 +421,17 @@ def find_batch_file(env,msvc_version,host_arch,target_arch):
         debug("Not found: %s" % batfilename)
         batfilename = None
 
-    installed_sdks=get_installed_sdks()
+    installed_sdks = get_installed_sdks()
     for _sdk in installed_sdks:
         sdk_bat_file = _sdk.get_sdk_vc_script(host_arch,target_arch)
         if not sdk_bat_file:
-            debug("vc.py:find_batch_file() not found:%s"%_sdk)
+            debug("find_batch_file() not found:%s"%_sdk)
         else:
             sdk_bat_file_path = os.path.join(pdir,sdk_bat_file)
             if os.path.exists(sdk_bat_file_path):
-                debug('vc.py:find_batch_file() sdk_bat_file_path:%s'%sdk_bat_file_path)
-                return (batfilename,sdk_bat_file_path)
-    return (batfilename,None)
+                debug('find_batch_file() sdk_bat_file_path:%s'%sdk_bat_file_path)
+                return (batfilename, sdk_bat_file_path)
+    return (batfilename, None)
 
 
 __INSTALLED_VCS_RUN = None
@@ -592,21 +590,57 @@ def reset_installed_vcs():
 #    env2 = Environment(tools='msvs')
 # we can greatly improve the speed of the second and subsequent Environment
 # (or Clone) calls by memoizing the environment variables set by vcvars*.bat.
-script_env_stdout_cache = {}
+#
+# Updated: by 2018, vcvarsall.bat had gotten so expensive (vs2017 era)
+# it was breaking CI builds because the test suite starts scons so many
+# times and the existing memo logic only helped with repeated calls
+# within the same scons run. Windows builds on the CI system were split
+# into chunks to get around single-build time limits.
+# With VS2019 it got even slower and an optional persistent cache file
+# was introduced. The cache now also stores only the parsed vars, 
+# not the entire output of running the batch file - saves a bit
+# of time not parsing every time.
+
+script_env_cache = None
+
 def script_env(script, args=None):
-    cache_key = (script, args)
-    stdout = script_env_stdout_cache.get(cache_key, None)
-    if stdout is None:
+    global script_env_cache
+
+    if script_env_cache is None:
+        script_env_cache = common.read_script_env_cache()
+    cache_key = "{}--{}".format(script, args)
+    cache_data = script_env_cache.get(cache_key, None)
+    if cache_data is None:
         stdout = common.get_output(script, args)
-        script_env_stdout_cache[cache_key] = stdout
 
-    # Stupid batch files do not set return code: we take a look at the
-    # beginning of the output for an error message instead
-    olines = stdout.splitlines()
-    if olines[0].startswith("The specified configuration type is missing"):
-        raise BatchFileExecutionError("\n".join(olines[:2]))
+        # Stupid batch files do not set return code: we take a look at the
+        # beginning of the output for an error message instead
+        olines = stdout.splitlines()
+        if olines[0].startswith("The specified configuration type is missing"):
+            raise BatchFileExecutionError("\n".join(olines[:2]))
+
+        cache_data = common.parse_output(stdout)
+        script_env_cache[cache_key] = cache_data
+        # once we updated cache, give a chance to write out if user wanted
+        common.write_script_env_cache(script_env_cache)
+    else:
+        #TODO: Python 2 cleanup
+        # If we "hit" data from the json file, we have a Py2 problem:
+        # keys & values will be unicode. don't detect, just convert.
+        if sys.version_info[0] == 2:
+            def convert(data):
+                if isinstance(data, basestring):
+                    return str(data)
+                elif isinstance(data, collections.Mapping):
+                    return dict(map(convert, data.iteritems()))
+                elif isinstance(data, collections.Iterable):
+                    return type(data)(map(convert, data))
+                else:
+                    return data
 
-    return common.parse_output(stdout)
+            cache_data = convert(cache_data)
+ 
+    return cache_data
 
 def get_default_version(env):
     debug('get_default_version()')
@@ -635,12 +669,12 @@ def get_default_version(env):
         debug('installed_vcs:%s' % installed_vcs)
         if not installed_vcs:
             #msg = 'No installed VCs'
-            #debug('msv %s\n' % repr(msg))
+            #debug('msv %s' % repr(msg))
             #SCons.Warnings.warn(SCons.Warnings.VisualCMissingWarning, msg)
             debug('msvc_setup_env: No installed VCs')
             return None
         msvc_version = installed_vcs[0]
-        debug('msvc_setup_env: using default installed MSVC version %s\n' % repr(msvc_version))
+        debug('msvc_setup_env: using default installed MSVC version %s' % repr(msvc_version))
 
     return msvc_version
 
@@ -654,12 +688,12 @@ def msvc_setup_env_once(env):
         msvc_setup_env(env)
         env["MSVC_SETUP_RUN"] = True
 
-def msvc_find_valid_batch_script(env,version):
-    debug('vc.py:msvc_find_valid_batch_script()')
+def msvc_find_valid_batch_script(env, version):
+    debug('msvc_find_valid_batch_script()')
     # Find the host platform, target platform, and if present the requested
     # target platform
     platforms = get_host_target(env)
-    debug("vc.py: msvs_find_valid_batch_script(): host_platform %s, target_platform %s req_target_platform:%s" % platforms)
+    debug(" msvs_find_valid_batch_script(): host_platform %s, target_platform %s req_target_platform:%s" % platforms)
 
     host_platform, target_platform, req_target_platform = platforms
     try_target_archs = [target_platform]
@@ -683,7 +717,7 @@ def msvc_find_valid_batch_script(env,version):
         # Set to current arch.
         env['TARGET_ARCH']=tp
 
-        debug("vc.py:msvc_find_valid_batch_script() trying target_platform:%s"%tp)
+        debug("msvc_find_valid_batch_script() trying target_platform:%s"%tp)
         host_target = (host_platform, tp)
         if not is_host_target_supported(host_target, version):
             warn_msg = "host, target = %s not supported for MSVC version %s" % \
@@ -701,8 +735,8 @@ def msvc_find_valid_batch_script(env,version):
 
         # Try to locate a batch file for this host/target platform combo
         try:
-            (vc_script,sdk_script) = find_batch_file(env,version,host_platform,tp)
-            debug('vc.py:msvc_find_valid_batch_script() vc_script:%s sdk_script:%s'%(vc_script,sdk_script))
+            (vc_script, sdk_script) = find_batch_file(env, version, host_platform, tp)
+            debug('msvc_find_valid_batch_script() vc_script:%s sdk_script:%s'%(vc_script,sdk_script))
         except VisualCException as e:
             msg = str(e)
             debug('Caught exception while looking for batch file (%s)' % msg)
@@ -714,29 +748,29 @@ def msvc_find_valid_batch_script(env,version):
             continue
 
         # Try to use the located batch file for this host/target platform combo
-        debug('vc.py:msvc_find_valid_batch_script() use_script 2 %s, args:%s\n' % (repr(vc_script), arg))
+        debug('msvc_find_valid_batch_script() use_script 2 %s, args:%s' % (repr(vc_script), arg))
         found = None
         if vc_script:
             try:
                 d = script_env(vc_script, args=arg)
                 found = vc_script
             except BatchFileExecutionError as e:
-                debug('vc.py:msvc_find_valid_batch_script() use_script 3: failed running VC script %s: %s: Error:%s'%(repr(vc_script),arg,e))
+                debug('msvc_find_valid_batch_script() use_script 3: failed running VC script %s: %s: Error:%s'%(repr(vc_script),arg,e))
                 vc_script=None
                 continue
         if not vc_script and sdk_script:
-            debug('vc.py:msvc_find_valid_batch_script() use_script 4: trying sdk script: %s'%(sdk_script))
+            debug('msvc_find_valid_batch_script() use_script 4: trying sdk script: %s'%(sdk_script))
             try:
                 d = script_env(sdk_script)
                 found = sdk_script
             except BatchFileExecutionError as e:
-                debug('vc.py:msvc_find_valid_batch_script() use_script 5: failed running SDK script %s: Error:%s'%(repr(sdk_script),e))
+                debug('msvc_find_valid_batch_script() use_script 5: failed running SDK script %s: Error:%s'%(repr(sdk_script),e))
                 continue
         elif not vc_script and not sdk_script:
-            debug('vc.py:msvc_find_valid_batch_script() use_script 6: Neither VC script nor SDK script found')
+            debug('msvc_find_valid_batch_script() use_script 6: Neither VC script nor SDK script found')
             continue
 
-        debug("vc.py:msvc_find_valid_batch_script() Found a working script/target: %s/%s"%(repr(found),arg))
+        debug("msvc_find_valid_batch_script() Found a working script/target: %s/%s"%(repr(found),arg))
         break # We've found a working target_platform, so stop looking
 
     # If we cannot find a viable installed compiler, reset the TARGET_ARCH
@@ -756,7 +790,7 @@ def msvc_setup_env(env):
                    "compilers most likely not set correctly"
         SCons.Warnings.warn(SCons.Warnings.VisualCMissingWarning, warn_msg)
         return None
-    debug('msvc_setup_env: using specified MSVC version %s\n' % repr(version))
+    debug('msvc_setup_env: using specified MSVC version %s' % repr(version))
 
     # XXX: we set-up both MSVS version for backward
     # compatibility with the msvs tool
@@ -767,11 +801,11 @@ def msvc_setup_env(env):
 
     use_script = env.get('MSVC_USE_SCRIPT', True)
     if SCons.Util.is_String(use_script):
-        debug('vc.py:msvc_setup_env() use_script 1 %s\n' % repr(use_script))
+        debug('msvc_setup_env() use_script 1 %s' % repr(use_script))
         d = script_env(use_script)
     elif use_script:
         d = msvc_find_valid_batch_script(env,version)
-        debug('vc.py:msvc_setup_env() use_script 2 %s\n' % d)
+        debug('msvc_setup_env() use_script 2 %s' % d)
         if not d:
             return d
     else:
@@ -782,7 +816,7 @@ def msvc_setup_env(env):
         return None
 
     for k, v in d.items():
-        debug('vc.py:msvc_setup_env() env:%s -> %s'%(k,v))
+        debug('msvc_setup_env() env:%s -> %s'%(k,v))
         env.PrependENVPath(k, v, delete_existing=True)
 
     # final check to issue a warning if the compiler is not present
diff --git a/src/engine/SCons/Tool/MSCommon/vs.py b/src/engine/SCons/Tool/MSCommon/vs.py
index dfca48d..bac35d8 100644
--- a/src/engine/SCons/Tool/MSCommon/vs.py
+++ b/src/engine/SCons/Tool/MSCommon/vs.py
@@ -465,14 +465,14 @@ def get_vs_by_version(msvs):
     global InstalledVSMap
     global SupportedVSMap
 
-    debug('vs.py:get_vs_by_version()')
+    debug('get_vs_by_version()')
     if msvs not in SupportedVSMap:
         msg = "Visual Studio version %s is not supported" % repr(msvs)
         raise SCons.Errors.UserError(msg)
     get_installed_visual_studios()
     vs = InstalledVSMap.get(msvs)
     debug('InstalledVSMap:%s'%InstalledVSMap)
-    debug('vs.py:get_vs_by_version: found vs:%s'%vs)
+    debug('get_vs_by_version: found vs:%s'%vs)
     # Some check like this would let us provide a useful error message
     # if they try to set a Visual Studio version that's not installed.
     # However, we also want to be able to run tests (like the unit
diff --git a/src/engine/SCons/Tool/__init__.xml b/src/engine/SCons/Tool/__init__.xml
index 69cc597..b6e5a43 100644
--- a/src/engine/SCons/Tool/__init__.xml
+++ b/src/engine/SCons/Tool/__init__.xml
@@ -468,7 +468,7 @@ as C++ files.
 Used to override &cv-link-SHLIBVERSION;/&cv-link-LDMODULEVERSION; when
 generating versioned import library for a shared library/loadable module. If
 undefined, the &cv-link-SHLIBVERSION;/&cv-link-LDMODULEVERSION; is used to
-determine the version of versioned import library. 
+determine the version of versioned import library.
 </para>
 </summary>
 </cvar>
@@ -476,7 +476,10 @@ determine the version of versioned import library.
 <cvar name="LIBEMITTER">
 <summary>
 <para>
-TODO
+Contains the emitter specification for the
+&b-link-StaticLibrary; builder.
+The manpage section "Builder Objects" contains
+general information on specifying emitters.
 </para>
 </summary>
 </cvar>
@@ -494,10 +497,24 @@ format as &cv-link-SHLIBVERSION;.
 </summary>
 </cvar>
 
+<cvar name="LDMODULEEMITTER">
+<summary>
+<para>
+Contains the emitter specification for the
+&b-link-LoadableModule; builder.
+The manpage section "Builder Objects" contains
+general information on specifying emitters.
+</para>
+</summary>
+</cvar>
+
 <cvar name="SHLIBEMITTER">
 <summary>
 <para>
-TODO
+Contains the emitter specification for the
+&b-link-SharedLibrary; builder.
+The manpage section "Builder Objects" contains
+general information on specifying emitters.
 </para>
 </summary>
 </cvar>
@@ -505,7 +522,10 @@ TODO
 <cvar name="PROGEMITTER">
 <summary>
 <para>
-TODO
+Contains the emitter specification for the
+&b-link-Program; builder.
+The manpage section "Builder Objects" contains
+general information on specifying emitters.
 </para>
 </summary>
 </cvar>
@@ -514,7 +534,7 @@ TODO
 <summary>
 <para>
 When this construction variable is defined, a versioned shared library
-is created by &b-link-SharedLibrary; builder. This activates the
+is created by the &b-link-SharedLibrary; builder. This activates the
 &cv-link-_SHLIBVERSIONFLAGS; and thus modifies the &cv-link-SHLINKCOM; as
 required, adds the version number to the library name, and creates the symlinks
 that are needed.  &cv-link-SHLIBVERSION; versions should exist as alpha-numeric,
diff --git a/src/engine/SCons/Tool/cc.xml b/src/engine/SCons/Tool/cc.xml
index 9330436..7ce8b36 100644
--- a/src/engine/SCons/Tool/cc.xml
+++ b/src/engine/SCons/Tool/cc.xml
@@ -26,7 +26,7 @@ See its __doc__ string for a discussion of the format.
 <tool name="cc">
 <summary>
 <para>
-Sets construction variables for generic POSIX C copmilers.
+Sets construction variables for generic POSIX C compilers.
 </para>
 </summary>
 <sets>
diff --git a/src/engine/SCons/Tool/default.xml b/src/engine/SCons/Tool/default.xml
index 38eb122..4b862fb 100644
--- a/src/engine/SCons/Tool/default.xml
+++ b/src/engine/SCons/Tool/default.xml
@@ -26,10 +26,91 @@ See its __doc__ string for a discussion of the format.
 <tool name="default">
 <summary>
 <para>
-Sets variables by calling a default list of Tool modules
-for the platform on which SCons is running.
+Sets &consvars; for a default list of Tool modules.
+Use <emphasis role="bold">default</emphasis>
+in the tools list to retain the original defaults,
+since the <parameter>tools</parameter> parameter
+is treated as a literal statement of the tools
+to be made available in that &consenv;, not an addition.
 </para>
+
+<para>
+The list of tools selected by default is not static,
+but is dependent both on
+the platform and on the software installed on the platform.
+Some tools will not initialize if an underlying command is
+not found, and some tools are selected from a list of choices
+on a first-found basis. The finished tool list can be
+examined by inspecting the <envar>TOOLS</envar> &consvar;
+in the &consenv;.
+</para>
+
+<para>
+On all platforms, all tools from the following list
+are selected whose respective conditions are met:
+filesystem, wix, lex, yacc, rpcgen, swig,
+jar, javac, javah, rmic, dvipdf, dvips, gs,
+tex, latex, pdflatex, pdftex, tar, zip, textfile.
+</para>
+
+<para>
+On Linux systems, the default tools list selects
+(first-found): a C compiler from
+gcc, intelc, icc, cc;
+a C++ compiler from
+g++, intelc, icc, cxx;
+an assembler from
+gas, nasm, masm;
+a linker from
+gnulink, ilink;
+a Fortran compiler from
+gfortran, g77, ifort, ifl, f95, f90, f77;
+and a static archiver 'ar'.
+It also selects all found from the list
+m4, rpm.
+</para>
+
+<para>
+On Windows systems, the default tools list selects
+(first-found): a C compiler from
+msvc, mingw, gcc, intelc, icl, icc, cc, bcc32;
+a C++ compiler from
+msvc, intelc, icc, g++, cxx, bcc32;
+an assembler from
+masm, nasm, gas, 386asm;
+a linker from
+mslink, gnulink, ilink, linkloc, ilink32;
+a Fortran compiler from
+gfortran, g77, ifl, cvf, f95, f90, fortran;
+and a static archiver from
+mslib, ar, tlib;
+It also selects all found from the list
+msvs, midl.
+</para>
+
+<para>
+On MacOS systems, the default tools list selects
+(first-found): a C compiler from
+gcc, cc;
+a C++ compiler from
+g++, cxx;
+an assembler 'as';
+a linker from
+applelink, gnulink;
+a Fortran compiler from
+gfortran, f95, f90, g77;
+and a static archiver ar.
+It also selects all found from the list
+m4, rpm.
+</para>
+
+<para>
+Default lists for other platforms can be found by
+examining the &scons;
+source code (see
+<filename>SCons/Tool/__init__.py</filename>).
+</para>
+
 </summary>
 </tool>
-
 </sconsdoc>
diff --git a/src/engine/SCons/Tool/dmd.xml b/src/engine/SCons/Tool/dmd.xml
index 7e220dc..a3620ce 100644
--- a/src/engine/SCons/Tool/dmd.xml
+++ b/src/engine/SCons/Tool/dmd.xml
@@ -73,299 +73,4 @@ Sets construction variables for D language compiler DMD.
 </uses>
 </tool>
 
-<cvar name="DC">
-<summary>
-<para>
-The D compiler to use.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DCOM">
-<summary>
-<para>
-  The command line used to compile a D file to an object file.
-  Any options specified in the &cv-link-DFLAGS; construction variable
-  is included on this command line.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DDEBUG">
-<summary>
-<para>
-  List of debug tags to enable when compiling.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DFLAGS">
-<summary>
-<para>
-  General options that are passed to the D compiler.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLIB">
-<summary>
-<para>
-  Name of the lib tool to use for D codes.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLIBCOM">
-<summary>
-<para>
-  The command line to use when creating libraries.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLINK">
-<summary>
-<para>
-  Name of the linker to use for linking systems including D sources.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLINKCOM">
-<summary>
-<para>
-  The command line to use when linking systems including D sources.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLINKFLAGS">
-<summary>
-<para>
-List of linker flags.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DPATH">
-<summary>
-<para>
-  List of paths to search for import modules.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DVERSIONS">
-<summary>
-<para>
-  List of version tags to enable when compiling.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDC">
-<summary>
-<para>
-  The name of the compiler to use when compiling D source
-  destined to be in a shared objects.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDCOM">
-<summary>
-<para>
-  The command line to use when compiling code to be part of shared objects.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDLINK">
-<summary>
-<para>
-  The linker to use when creating shared objects for code bases
-  include D sources.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDLINKCOM">
-<summary>
-<para>
-  The command line to use when generating shared objects.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDLINKFLAGS">
-<summary>
-<para>
-  The list of flags to use when generating a shared object.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DVERSUFFIX">
-  <summary>
-    <para>
-      DVERSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DVERPREFIX">
-  <summary>
-    <para>
-      DVERPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLINKFLAGSUFFIX">
-  <summary>
-    <para>
-      DLINKFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLINKFLAGPREFIX">
-  <summary>
-    <para>
-      DLINKFLAGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBLINKSUFFIX">
-  <summary>
-    <para>
-      DLIBLINKSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBLINKPREFIX">
-  <summary>
-    <para>
-      DLIBLINKPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBFLAGSUFFIX">
-  <summary>
-    <para>
-      DLIBFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBFLAGPREFIX">
-  <summary>
-    <para>
-      DLIBFLAGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBDIRSUFFIX">
-  <summary>
-    <para>
-      DLIBLINKSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBDIRPREFIX">
-  <summary>
-    <para>
-      DLIBLINKPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DINCSUFFIX">
-  <summary>
-    <para>
-      DLIBFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-
-<cvar name="DINCPREFIX">
-  <summary>
-    <para>
-      DINCPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DFLAGSUFFIX">
-  <summary>
-    <para>
-      DFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DFLAGPREFIX">
-  <summary>
-    <para>
-      DFLAGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DFILESUFFIX">
-  <summary>
-    <para>
-      DFILESUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DDEBUGPREFIX">
-  <summary>
-    <para>
-      DDEBUGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DDEBUGSUFFIX">
-  <summary>
-    <para>
-      DDEBUGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<builder name="ProgramAllAtOnce">
-  <summary>
-    <para>
-      Builds an executable from D sources without first creating individual
-      objects for each file.
-    </para>
-    <para>
-      D sources can be compiled file-by-file as C and C++ source are, and
-      D is integrated into the &scons; Object and Program builders for
-      this model of build. D codes can though do whole source
-      meta-programming (some of the testing frameworks do this). For this
-      it is imperative that all sources are compiled and linked in a single call of
-      the D compiler. This builder serves that purpose.
-    </para>
-    <example_commands>
-      env.ProgramAllAtOnce('executable', ['mod_a.d, mod_b.d', 'mod_c.d'])
-    </example_commands>
-    <para>
-      This command will compile the modules mod_a, mod_b, and mod_c in a
-      single compilation process without first creating object files for
-      the modules. Some of the D compilers will create executable.o others
-      will not.
-    </para>
-  </summary>
-</builder>
-
 </sconsdoc>
diff --git a/src/engine/SCons/Tool/gdc.xml b/src/engine/SCons/Tool/gdc.xml
index d44489e..4c6c2f8 100644
--- a/src/engine/SCons/Tool/gdc.xml
+++ b/src/engine/SCons/Tool/gdc.xml
@@ -73,299 +73,4 @@ Sets construction variables for the D language compiler GDC.
 </uses>
 </tool>
 
-<cvar name="DC">
-<summary>
-<para>
-The D compiler to use.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DCOM">
-<summary>
-<para>
-  The command line used to compile a D file to an object file.
-  Any options specified in the &cv-link-DFLAGS; construction variable
-  is included on this command line.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DDEBUG">
-<summary>
-<para>
-  List of debug tags to enable when compiling.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DFLAGS">
-<summary>
-<para>
-  General options that are passed to the D compiler.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLIB">
-<summary>
-<para>
-  Name of the lib tool to use for D codes.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLIBCOM">
-<summary>
-<para>
-  The command line to use when creating libraries.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLINK">
-<summary>
-<para>
-  Name of the linker to use for linking systems including D sources.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLINKCOM">
-<summary>
-<para>
-  The command line to use when linking systems including D sources.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLINKFLAGS">
-<summary>
-<para>
-List of linker flags.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DPATH">
-<summary>
-<para>
-  List of paths to search for import modules.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DVERSIONS">
-<summary>
-<para>
-  List of version tags to enable when compiling.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDC">
-<summary>
-<para>
-  The name of the compiler to use when compiling D source
-  destined to be in a shared objects.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDCOM">
-<summary>
-<para>
-  The command line to use when compiling code to be part of shared objects.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDLINK">
-<summary>
-<para>
-  The linker to use when creating shared objects for code bases
-  include D sources.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDLINKCOM">
-<summary>
-<para>
-  The command line to use when generating shared objects.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDLINKFLAGS">
-<summary>
-<para>
-  The list of flags to use when generating a shared object.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DVERSUFFIX">
-  <summary>
-    <para>
-      DVERSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DVERPREFIX">
-  <summary>
-    <para>
-      DVERPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLINKFLAGSUFFIX">
-  <summary>
-    <para>
-      DLINKFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLINKFLAGPREFIX">
-  <summary>
-    <para>
-      DLINKFLAGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBLINKSUFFIX">
-  <summary>
-    <para>
-      DLIBLINKSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBLINKPREFIX">
-  <summary>
-    <para>
-      DLIBLINKPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBFLAGSUFFIX">
-  <summary>
-    <para>
-      DLIBFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBFLAGPREFIX">
-  <summary>
-    <para>
-      DLIBFLAGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBDIRSUFFIX">
-  <summary>
-    <para>
-      DLIBLINKSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBDIRPREFIX">
-  <summary>
-    <para>
-      DLIBLINKPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DINCSUFFIX">
-  <summary>
-    <para>
-      DLIBFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-
-<cvar name="DINCPREFIX">
-  <summary>
-    <para>
-      DINCPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DFLAGSUFFIX">
-  <summary>
-    <para>
-      DFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DFLAGPREFIX">
-  <summary>
-    <para>
-      DFLAGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DFILESUFFIX">
-  <summary>
-    <para>
-      DFILESUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DDEBUGPREFIX">
-  <summary>
-    <para>
-      DDEBUGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DDEBUGSUFFIX">
-  <summary>
-    <para>
-      DDEBUGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<builder name="ProgramAllAtOnce">
-  <summary>
-    <para>
-      Builds an executable from D sources without first creating individual
-      objects for each file.
-    </para>
-    <para>
-      D sources can be compiled file-by-file as C and C++ source are, and
-      D is integrated into the &scons; Object and Program builders for
-      this model of build. D codes can though do whole source
-      meta-programming (some of the testing frameworks do this). For this
-      it is imperative that all sources are compiled and linked in a single call of
-      the D compiler. This builder serves that purpose.
-    </para>
-    <example_commands>
-      env.ProgramAllAtOnce('executable', ['mod_a.d, mod_b.d', 'mod_c.d'])
-    </example_commands>
-    <para>
-      This command will compile the modules mod_a, mod_b, and mod_c in a
-      single compilation process without first creating object files for
-      the modules. Some of the D compilers will create executable.o others
-      will not.
-    </para>
-  </summary>
-</builder>
-
 </sconsdoc>
diff --git a/src/engine/SCons/Tool/install.xml b/src/engine/SCons/Tool/install.xml
index 6ae3e30..74169b3 100644
--- a/src/engine/SCons/Tool/install.xml
+++ b/src/engine/SCons/Tool/install.xml
@@ -52,6 +52,22 @@ a builder.
 <example_commands>
 env.Install('/usr/local/bin', source = ['foo', 'bar'])
 </example_commands>
+
+<para>
+If the <option>--install-sandbox</option> command line
+option is given, the target directory will be prefixed
+by the directory path specified.
+This is useful to test installs without installing to
+a "live" location in the system.
+</para>
+
+<para>
+See also &FindInstalledFiles;.
+For more thoughts on installation, see the User Guide
+(particularly the section on Command-Line Targets
+and the chapters on Installing Files and on Alias Targets).
+</para>
+
 </summary>
 </builder>
 
diff --git a/src/engine/SCons/Tool/ldc.xml b/src/engine/SCons/Tool/ldc.xml
index 495b8bc..6a80436 100644
--- a/src/engine/SCons/Tool/ldc.xml
+++ b/src/engine/SCons/Tool/ldc.xml
@@ -73,299 +73,4 @@ Sets construction variables for the D language compiler LDC2.
 </uses>
 </tool>
 
-<cvar name="DC">
-<summary>
-<para>
-The D compiler to use.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DCOM">
-<summary>
-<para>
-  The command line used to compile a D file to an object file.
-  Any options specified in the &cv-link-DFLAGS; construction variable
-  is included on this command line.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DDEBUG">
-<summary>
-<para>
-  List of debug tags to enable when compiling.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DFLAGS">
-<summary>
-<para>
-  General options that are passed to the D compiler.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLIB">
-<summary>
-<para>
-  Name of the lib tool to use for D codes.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLIBCOM">
-<summary>
-<para>
-  The command line to use when creating libraries.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLINK">
-<summary>
-<para>
-  Name of the linker to use for linking systems including D sources.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLINKCOM">
-<summary>
-<para>
-  The command line to use when linking systems including D sources.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DLINKFLAGS">
-<summary>
-<para>
-List of linker flags.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DPATH">
-<summary>
-<para>
-  List of paths to search for import modules.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DVERSIONS">
-<summary>
-<para>
-  List of version tags to enable when compiling.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDC">
-<summary>
-<para>
-  The name of the compiler to use when compiling D source
-  destined to be in a shared objects.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDCOM">
-<summary>
-<para>
-  The command line to use when compiling code to be part of shared objects.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDLINK">
-<summary>
-<para>
-  The linker to use when creating shared objects for code bases
-  include D sources.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDLINKCOM">
-<summary>
-<para>
-  The command line to use when generating shared objects.
-</para>
-</summary>
-</cvar>
-
-<cvar name="SHDLINKFLAGS">
-<summary>
-<para>
-  The list of flags to use when generating a shared object.
-</para>
-</summary>
-</cvar>
-
-<cvar name="DVERSUFFIX">
-  <summary>
-    <para>
-      DVERSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DVERPREFIX">
-  <summary>
-    <para>
-      DVERPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLINKFLAGSUFFIX">
-  <summary>
-    <para>
-      DLINKFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLINKFLAGPREFIX">
-  <summary>
-    <para>
-      DLINKFLAGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBLINKSUFFIX">
-  <summary>
-    <para>
-      DLIBLINKSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBLINKPREFIX">
-  <summary>
-    <para>
-      DLIBLINKPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBFLAGSUFFIX">
-  <summary>
-    <para>
-      DLIBFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBFLAGPREFIX">
-  <summary>
-    <para>
-      DLIBFLAGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBDIRSUFFIX">
-  <summary>
-    <para>
-      DLIBLINKSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DLIBDIRPREFIX">
-  <summary>
-    <para>
-      DLIBLINKPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DINCSUFFIX">
-  <summary>
-    <para>
-      DLIBFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-
-<cvar name="DINCPREFIX">
-  <summary>
-    <para>
-      DINCPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DFLAGSUFFIX">
-  <summary>
-    <para>
-      DFLAGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DFLAGPREFIX">
-  <summary>
-    <para>
-      DFLAGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DFILESUFFIX">
-  <summary>
-    <para>
-      DFILESUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DDEBUGPREFIX">
-  <summary>
-    <para>
-      DDEBUGPREFIX.
-    </para>
- </summary>
-</cvar>
-
-<cvar name="DDEBUGSUFFIX">
-  <summary>
-    <para>
-      DDEBUGSUFFIX.
-    </para>
- </summary>
-</cvar>
-
-<builder name="ProgramAllAtOnce">
-  <summary>
-    <para>
-      Builds an executable from D sources without first creating individual
-      objects for each file.
-    </para>
-    <para>
-      D sources can be compiled file-by-file as C and C++ source are, and
-      D is integrated into the &scons; Object and Program builders for
-      this model of build. D codes can though do whole source
-      meta-programming (some of the testing frameworks do this). For this
-      it is imperative that all sources are compiled and linked in a single call of
-      the D compiler. This builder serves that purpose.
-    </para>
-    <example_commands>
-      env.ProgramAllAtOnce('executable', ['mod_a.d, mod_b.d', 'mod_c.d'])
-    </example_commands>
-    <para>
-      This command will compile the modules mod_a, mod_b, and mod_c in a
-      single compilation process without first creating object files for
-      the modules. Some of the D compilers will create executable.o others
-      will not.
-    </para>
-  </summary>
-</builder>
-
 </sconsdoc>
diff --git a/src/engine/SCons/Tool/link.xml b/src/engine/SCons/Tool/link.xml
index 2f913fe..75b2ed8 100644
--- a/src/engine/SCons/Tool/link.xml
+++ b/src/engine/SCons/Tool/link.xml
@@ -26,7 +26,9 @@ See its __doc__ string for a discussion of the format.
 <tool name="link">
 <summary>
 <para>
-Sets construction variables for generic POSIX linkers.
+Sets construction variables for generic POSIX linkers. This is
+a "smart" linker tool which selects a compiler to complete the linking
+based on the types of source files.
 </para>
 </summary>
 <sets>
diff --git a/src/engine/SCons/Tool/midl.xml b/src/engine/SCons/Tool/midl.xml
index efd83cc..63cf527 100644
--- a/src/engine/SCons/Tool/midl.xml
+++ b/src/engine/SCons/Tool/midl.xml
@@ -86,7 +86,7 @@ The command line used to pass files to the Microsoft IDL compiler.
 <summary>
 <para>
 The string displayed when
-the Microsoft IDL copmiler is called.
+the Microsoft IDL compiler is called.
 If this is not set, then &cv-link-MIDLCOM; (the command line) is displayed.
 </para>
 </summary>
diff --git a/src/engine/SCons/Tool/msvs.py b/src/engine/SCons/Tool/msvs.py
index d27294b..7dca9e1 100644
--- a/src/engine/SCons/Tool/msvs.py
+++ b/src/engine/SCons/Tool/msvs.py
@@ -652,7 +652,7 @@ class _GenerateV6DSP(_DSPGenerator):
             for base in ("BASE ",""):
                 self.file.write('# PROP %sUse_MFC 0\n'
                                 '# PROP %sUse_Debug_Libraries ' % (base, base))
-                if kind.lower().find('debug') < 0:
+                if 'debug' not in kind.lower():
                     self.file.write('0\n')
                 else:
                     self.file.write('1\n')
@@ -731,7 +731,7 @@ class _GenerateV6DSP(_DSPGenerator):
         line = dspfile.readline()
         # skip until marker
         while line:
-            if line.find("# End Project") > -1:
+            if "# End Project" in line:
                 break
             line = dspfile.readline()
 
@@ -1049,7 +1049,7 @@ class _GenerateV7DSP(_DSPGenerator, _GenerateV7User):
         line = dspfile.readline()
         # skip until marker
         while line:
-            if line.find('<!-- SCons Data:') > -1:
+            if '<!-- SCons Data:' in line:
                 break
             line = dspfile.readline()
 
diff --git a/src/engine/SCons/Tool/suncxx.py b/src/engine/SCons/Tool/suncxx.py
index 9ac8d32..090df7d 100644
--- a/src/engine/SCons/Tool/suncxx.py
+++ b/src/engine/SCons/Tool/suncxx.py
@@ -74,7 +74,7 @@ def get_package_info(package_name, pkginfo, pkgchk):
         except EnvironmentError:
             pass
         else:
-            pkginfo_contents = p.communicate()[0]
+            pkginfo_contents = p.communicate()[0].decode()
             version_re = re.compile(r'^ *VERSION:\s*(.*)$', re.M)
             version_match = version_re.search(pkginfo_contents)
             if version_match:
@@ -88,7 +88,7 @@ def get_package_info(package_name, pkginfo, pkgchk):
             except EnvironmentError:
                 pass
             else:
-                pkgchk_contents = p.communicate()[0]
+                pkgchk_contents = p.communicate()[0].decode()
                 pathname_re = re.compile(r'^Pathname:\s*(.*/bin/CC)$', re.M)
                 pathname_match = pathname_re.search(pkgchk_contents)
                 if pathname_match:
diff --git a/src/engine/SCons/Tool/swig.py b/src/engine/SCons/Tool/swig.py
index 6ed9d82..f139a09 100644
--- a/src/engine/SCons/Tool/swig.py
+++ b/src/engine/SCons/Tool/swig.py
@@ -80,7 +80,7 @@ def _find_modules(src):
 
     for m in matches:
         mnames.append(m[2])
-        directors = directors or m[0].find('directors') >= 0
+        directors = directors or 'directors' in m[0]
     return mnames, directors
 
 def _add_director_header_targets(target, env):
diff --git a/src/engine/SCons/Warnings.py b/src/engine/SCons/Warnings.py
index a5b257b..718b3d5 100644
--- a/src/engine/SCons/Warnings.py
+++ b/src/engine/SCons/Warnings.py
@@ -132,12 +132,6 @@ class DeprecatedCopyWarning(MandatoryDeprecatedWarning):
 class DeprecatedOptionsWarning(MandatoryDeprecatedWarning):
     pass
 
-class DeprecatedSourceSignaturesWarning(MandatoryDeprecatedWarning):
-    pass
-
-class DeprecatedTargetSignaturesWarning(MandatoryDeprecatedWarning):
-    pass
-
 class DeprecatedDebugOptionsWarning(MandatoryDeprecatedWarning):
     pass