diff -r 01d91caa58b6 Lib/distutils/spawn.py
--- a/Lib/distutils/spawn.py	Tue Aug 18 13:27:18 2015 -0400
+++ b/Lib/distutils/spawn.py	Tue Aug 18 13:09:34 2015 -0500
@@ -8,6 +8,7 @@
 
 import sys
 import os
+import re
 
 from distutils.errors import DistutilsPlatformError, DistutilsExecError
 from distutils.debug import DEBUG
@@ -43,17 +44,32 @@
 def _nt_quote_args(args):
     """Quote command-line arguments for DOS/Windows conventions.
 
-    Just wraps every argument which contains blanks in double quotes, and
-    returns a new argument list.
+    Wraps every argument which contains special characters in double quotes,
+    removes trailing backslashes from paths, properly escapes double quotes,
+    and returns a new argument list.
     """
-    # XXX this doesn't seem very robust to me -- but if the Windows guys
-    # say it'll work, I guess I'll have to accept it.  (What if an arg
-    # contains quotes?  What other magic characters, other than spaces,
-    # have to be escaped?  Is there an escaping mechanism other than
-    # quoting?)
+
+    def has_balanced_quotes(arg):
+        return arg[0] == arg[-1] == '"' or arg[0] == arg[-1] == '\''
+
+    def is_unquoted_with_special_char(arg):
+        return (re.search(r'[ &\|\(\)<>^"]', arg) is not None and
+                has_balanced_quotes(arg) is False)
+
     for i, arg in enumerate(args):
-        if ' ' in arg:
-            args[i] = '"%s"' % arg
+        # Quote anything with special characters and strip trailing backslash
+        if is_unquoted_with_special_char(arg):
+            args[i] = '"%s"' % arg.rstrip('\\')
+        # Check for trailing backslash in quoted arg
+        elif has_balanced_quotes(arg) and arg[-2] == '\\':
+            args[i] = arg[:-2] + arg[-1]
+        # Check for trailing backslash on unquoted paths without spaces
+        else:
+            args[i] = arg.rstrip('\\')
+        # Replace double quote in already quoted arg with ""
+        arg = args[i]
+        if arg[0] == '"':
+            args[i] = '"' + arg[1:-1].replace('"', '""') + '"'
     return args
 
 def _spawn_nt(cmd, search_path=1, verbose=0, dry_run=0):
diff -r 01d91caa58b6 Lib/distutils/tests/test_spawn.py
--- a/Lib/distutils/tests/test_spawn.py	Tue Aug 18 13:27:18 2015 -0400
+++ b/Lib/distutils/tests/test_spawn.py	Tue Aug 18 13:09:34 2015 -0500
@@ -18,7 +18,21 @@
         for (args, wanted) in ((['with space', 'nospace'],
                                 ['"with space"', 'nospace']),
                                (['nochange', 'nospace'],
-                                ['nochange', 'nospace'])):
+                                ['nochange', 'nospace']),
+                               (['space\\b slash\\', 'space\\no bslash'],
+                                ['"space\\b slash"', '"space\\no bslash"']),
+                               (['nospace\\bslash\\', 'nospace\\nobslash'],
+                                ['nospace\\bslash', 'nospace\\nobslash']),
+                               (['"space quoted"', '"nospacequoted"'],
+                                ['"space quoted"', '"nospacequoted"']),
+                               (['"quote\\space bs\\"', '"quote\\bslash\\"'],
+                                ['"quote\\space bs"', '"quote\\bslash"']),
+                               (['/LIBPATH:"C:\\quotes space"'],
+                                ['"/LIBPATH:""C:\\quotes space"""']),
+                               (['/DMODULE_VERSION="1.0.5"'],
+                                ['"/DMODULE_VERSION=""1.0.5"""']),
+                               (['"mismatchedquotes\d'],
+                                ['"""mismatchedquotes\d"'])):
             res = _nt_quote_args(args)
             self.assertEqual(res, wanted)