diff --git a/llvm/lib/System/AIX/Path.cpp b/llvm/lib/System/AIX/Path.cpp
index 117fbfb81bc2f3d6027628fb871d6f7203ae7e20..e49a593bc896cd0a0a8d312047321167938d5c8c 100644
--- a/llvm/lib/System/AIX/Path.cpp
+++ b/llvm/lib/System/AIX/Path.cpp
@@ -31,6 +31,18 @@ Path::is_valid() const {
   return true;
 }
 
+Path
+Path::GetTemporaryDirectory() {
+  char pathname[MAXPATHLEN];
+  strcpy(pathname,"/tmp/llvm_XXXXXX");
+  if (0 == mkdtemp(pathname))
+    ThrowErrno(std::string(pathname) + ": Can't create temporary directory");
+  Path result;
+  result.set_directory(pathname);
+  assert(result.is_valid() && "mkdtemp didn't create a valid pathname!");
+  return result;
+}
+
 }
 
 // vim: sw=2 smartindent smarttab tw=80 autoindent expandtab
diff --git a/llvm/lib/System/Cygwin/Path.cpp b/llvm/lib/System/Cygwin/Path.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..00fc5f229d185d046fdfbe3333005a8dcd1fde8f
--- /dev/null
+++ b/llvm/lib/System/Cygwin/Path.cpp
@@ -0,0 +1,50 @@
+//===- Cygwin/Path.cpp - Cygwin Path Implementation -------------*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Reid Spencer and is distributed under the 
+// University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+// This file provides the Cygwin specific implementation of the Path class.
+//
+//===----------------------------------------------------------------------===//
+
+//===----------------------------------------------------------------------===//
+//=== WARNING: Implementation here must contain only Cygwin specific code 
+//===          and must not be generic UNIX code (see ../Unix/Path.cpp)
+//===----------------------------------------------------------------------===//
+
+// Include the generic Unix implementation
+#include "../Unix/Path.cpp"
+
+namespace llvm {
+using namespace sys;
+
+bool 
+Path::is_valid() const {
+  if (path.empty()) 
+    return false;
+  char pathname[MAXPATHLEN];
+  if (0 == realpath(path.c_str(), pathname))
+    if (errno != EACCES && errno != EIO && errno != ENOENT && errno != ENOTDIR)
+      return false;
+  return true;
+}
+
+Path
+Path::GetTemporaryDirectory() {
+  char pathname[MAXPATHLEN];
+  strcpy(pathname,"/tmp/llvm_XXXXXX");
+  if (0 == mkdtemp(pathname))
+    ThrowErrno(std::string(pathname) + ": Can't create temporary directory");
+  Path result;
+  result.set_directory(pathname);
+  assert(result.is_valid() && "mkdtemp didn't create a valid pathname!");
+  return result;
+}
+
+}
+
+// vim: sw=2 smartindent smarttab tw=80 autoindent expandtab
diff --git a/llvm/lib/System/Darwin/Path.cpp b/llvm/lib/System/Darwin/Path.cpp
index b3321a47dfb6b3a42eff76a84b3b56d5d1e55a64..165bbc64b5ee24457293cbe8d01088aef87b05fd 100644
--- a/llvm/lib/System/Darwin/Path.cpp
+++ b/llvm/lib/System/Darwin/Path.cpp
@@ -31,6 +31,18 @@ Path::is_valid() const {
   return true;
 }
 
+Path
+Path::GetTemporaryDirectory() {
+  char pathname[MAXPATHLEN];
+  strcpy(pathname,"/tmp/llvm_XXXXXX");
+  if (0 == mkdtemp(pathname))
+    ThrowErrno(std::string(pathname) + ": Can't create temporary directory");
+  Path result;
+  result.set_directory(pathname);
+  assert(result.is_valid() && "mkdtemp didn't create a valid pathname!");
+  return result;
+}
+
 }
 
 // vim: sw=2 smartindent smarttab tw=80 autoindent expandtab
diff --git a/llvm/lib/System/Linux/Path.cpp b/llvm/lib/System/Linux/Path.cpp
index e7efd2fb955ceb5d68cde89e726f62733c3f1b75..8ec35b3c4a4aad7e3fbb64d16c70f9d146f771ba 100644
--- a/llvm/lib/System/Linux/Path.cpp
+++ b/llvm/lib/System/Linux/Path.cpp
@@ -33,6 +33,18 @@ Path::is_valid() const {
   return true;
 }
 
+Path
+Path::GetTemporaryDirectory() {
+  char pathname[MAXPATHLEN];
+  strcpy(pathname,"/tmp/llvm_XXXXXX");
+  if (0 == mkdtemp(pathname))
+    ThrowErrno(std::string(pathname) + ": Can't create temporary directory");
+  Path result;
+  result.set_directory(pathname);
+  assert(result.is_valid() && "mkdtemp didn't create a valid pathname!");
+  return result;
+}
+
 }
 
 // vim: sw=2 smartindent smarttab tw=80 autoindent expandtab
diff --git a/llvm/lib/System/SunOS/Path.cpp b/llvm/lib/System/SunOS/Path.cpp
index a180bbfe124fb584a024d2f8134717135392713c..3499d525874ad648ffa4731c6d719177dd09eaa0 100644
--- a/llvm/lib/System/SunOS/Path.cpp
+++ b/llvm/lib/System/SunOS/Path.cpp
@@ -33,6 +33,20 @@ Path::is_valid() const {
   return true;
 }
 
+Path
+Path::GetTemporaryDirectory() {
+  char* pathname = tempnam(0,"llvm_");
+  if (0 == pathname)
+    ThrowErrno(std::string("Can't create temporary directory name"));
+  Path result;
+  result.set_directory(pathname);
+  free(pathname);
+  assert(result.is_valid() && "tempnam didn't create a valid pathname!");
+  if (0 != mkdir(result.c_str(), S_IRWXU))
+    ThrowErrno(result.get() + ": Can't create temporary directory");
+  return result;
+}
+
 }
 
 // vim: sw=2 smartindent smarttab tw=80 autoindent expandtab
diff --git a/llvm/lib/System/Unix/Path.cpp b/llvm/lib/System/Unix/Path.cpp
index 9d9dd99103feac25d11758c736cd48f434bc6af2..9a860a0672f2b11b310683bf593c507aa1442e0d 100644
--- a/llvm/lib/System/Unix/Path.cpp
+++ b/llvm/lib/System/Unix/Path.cpp
@@ -43,18 +43,6 @@ Path::GetRootDirectory() {
   return result;
 }
 
-Path
-Path::GetTemporaryDirectory() {
-  char pathname[MAXPATHLEN];
-  strcpy(pathname,"/tmp/llvm_XXXXXX");
-  if (0 == mkdtemp(pathname))
-    ThrowErrno(std::string(pathname) + ": Can't create temporary directory");
-  Path result;
-  result.set_directory(pathname);
-  assert(result.is_valid() && "mkdtemp didn't create a valid pathname!");
-  return result;
-}
-
 Path 
 Path::GetSystemLibraryPath1() {
   return Path("/lib/");