diff --git a/llvm/lib/Support/Program.cpp b/llvm/lib/Support/Program.cpp
index 6e04a1cd536d..b1a9b98755ca 100644
--- a/llvm/lib/Support/Program.cpp
+++ b/llvm/lib/Support/Program.cpp
@@ -22,7 +22,7 @@ using namespace sys;
 //===          independent code.
 //===----------------------------------------------------------------------===//
 
-static bool Execute(void *&Data, const Path &path, const char **args,
+static bool Execute(void **Data, const Path &path, const char **args,
                     const char **env, const sys::Path **redirects,
                     unsigned memoryLimit, std::string *ErrMsg);
 
@@ -34,7 +34,7 @@ int sys::ExecuteAndWait(const Path &path, const char **args, const char **envp,
                         unsigned memoryLimit, std::string *ErrMsg,
                         bool *ExecutionFailed) {
   void *Data = 0;
-  if (Execute(Data, path, args, envp, redirects, memoryLimit, ErrMsg)) {
+  if (Execute(&Data, path, args, envp, redirects, memoryLimit, ErrMsg)) {
     if (ExecutionFailed) *ExecutionFailed = false;
     return Wait(Data, path, secondsToWait, ErrMsg);
   }
@@ -45,8 +45,7 @@ int sys::ExecuteAndWait(const Path &path, const char **args, const char **envp,
 void sys::ExecuteNoWait(const Path &path, const char **args, const char **envp,
                         const Path **redirects, unsigned memoryLimit,
                         std::string *ErrMsg) {
-  void *Data = 0;
-  Execute(Data, path, args, envp, redirects, memoryLimit, ErrMsg);
+  Execute(/*Data*/ 0, path, args, envp, redirects, memoryLimit, ErrMsg);
 }
 
 // Include the platform-specific parts of this class.
diff --git a/llvm/lib/Support/Unix/Program.inc b/llvm/lib/Support/Unix/Program.inc
index 0d6543a8a8c8..d8bdd6ce4247 100644
--- a/llvm/lib/Support/Unix/Program.inc
+++ b/llvm/lib/Support/Unix/Program.inc
@@ -178,7 +178,7 @@ static void SetMemoryLimits (unsigned size)
 
 }
 
-static bool Execute(void *&Data, const Path &path, const char **args,
+static bool Execute(void **Data, const Path &path, const char **args,
                     const char **envp, const Path **redirects,
                     unsigned memoryLimit, std::string *ErrMsg) {
   // If this OS has posix_spawn and there is no memory limit being implied, use
@@ -228,7 +228,8 @@ static bool Execute(void *&Data, const Path &path, const char **args,
     if (Err)
      return !MakeErrMsg(ErrMsg, "posix_spawn failed", Err);
 
-    Data = reinterpret_cast<void*>(PID);
+    if (Data)
+      *Data = reinterpret_cast<void*>(PID);
     return true;
   }
 #endif
@@ -290,7 +291,8 @@ static bool Execute(void *&Data, const Path &path, const char **args,
       break;
   }
 
-  Data = reinterpret_cast<void*>(child);
+  if (Data)
+    *Data = reinterpret_cast<void*>(child);
 
   return true;
 }
@@ -299,11 +301,7 @@ static int Wait(void *&Data, const sys::Path &path, unsigned secondsToWait,
                 std::string *ErrMsg) {
 #ifdef HAVE_SYS_WAIT_H
   struct sigaction Act, Old;
-
-  if (Data == 0) {
-    MakeErrMsg(ErrMsg, "Process not started!");
-    return -1;
-  }
+  assert(Data && "invalid pid to wait on, process not started?");
 
   // Install a timeout handler.  The handler itself does nothing, but the simple
   // fact of having a handler at all causes the wait below to return with EINTR,
diff --git a/llvm/lib/Support/Windows/Program.inc b/llvm/lib/Support/Windows/Program.inc
index 0e8bbc80a44f..90a5cdb78ffd 100644
--- a/llvm/lib/Support/Windows/Program.inc
+++ b/llvm/lib/Support/Windows/Program.inc
@@ -170,20 +170,13 @@ static unsigned int ArgLenWithQuotes(const char *Str) {
 
 }
 
-static bool Execute(void *&Data,
+static bool Execute(void **Data,
                     const Path& path,
                     const char** args,
                     const char** envp,
                     const Path** redirects,
                     unsigned memoryLimit,
                     std::string* ErrMsg) {
-  if (Data) {
-    Win32ProcessInfo* wpi = reinterpret_cast<Win32ProcessInfo*>(Data);
-    CloseHandle(wpi->hProcess);
-    delete wpi;
-    Data = 0;
-  }
-
   if (!path.canExecute()) {
     if (ErrMsg)
       *ErrMsg = "program not executable";
@@ -321,10 +314,12 @@ static bool Execute(void *&Data,
                path.str() + "'");
     return false;
   }
-  Win32ProcessInfo* wpi = new Win32ProcessInfo;
-  wpi->hProcess = pi.hProcess;
-  wpi->dwProcessId = pi.dwProcessId;
-  Data = wpi;
+  if (Data) {
+    Win32ProcessInfo* wpi = new Win32ProcessInfo;
+    wpi->hProcess = pi.hProcess;
+    wpi->dwProcessId = pi.dwProcessId;
+    *Data = wpi;
+  }
 
   // Make sure these get closed no matter what.
   ScopedCommonHandle hThread(pi.hThread);
@@ -354,21 +349,17 @@ static bool Execute(void *&Data,
     }
   }
 
+  // Don't leak the handle if the caller doesn't want it.
+  if (!Data)
+    CloseHandle(pi.hProcess);
+
   return true;
 }
 
-static int WaitAux(void *&Data, const Path &path,
-                   unsigned secondsToWait,
-                   std::string* ErrMsg) {
-  if (Data == 0) {
-    MakeErrMsg(ErrMsg, "Process not started!");
-    return -1;
-  }
-
-  Win32ProcessInfo* wpi = reinterpret_cast<Win32ProcessInfo*>(Data);
-  HANDLE hProcess = wpi->hProcess;
-
+static int WaitAux(Win32ProcessInfo *wpi, const Path &path,
+                   unsigned secondsToWait, std::string *ErrMsg) {
   // Wait for the process to terminate.
+  HANDLE hProcess = wpi->hProcess;
   DWORD millisecondsToWait = INFINITE;
   if (secondsToWait > 0)
     millisecondsToWait = secondsToWait * 1000;
@@ -407,12 +398,11 @@ static int WaitAux(void *&Data, const Path &path,
   return 1;
 }
 
-static int Wait(void *&Data, const Path &path,
-                unsigned secondsToWait,
-                std::string* ErrMsg) {
-  int Ret = WaitAux(Data, path, secondsToWait, ErrMsg);
+static int Wait(void *&Data, const Path &path, unsigned secondsToWait,
+                std::string *ErrMsg) {
+  Win32ProcessInfo *wpi = reinterpret_cast<Win32ProcessInfo *>(Data);
+  int Ret = WaitAux(wpi, path, secondsToWait, ErrMsg);
 
-  Win32ProcessInfo* wpi = reinterpret_cast<Win32ProcessInfo*>(Data);
   CloseHandle(wpi->hProcess);
   delete wpi;
   Data = 0;