Index: lib/Support/Signals.cpp
===================================================================
--- lib/Support/Signals.cpp
+++ lib/Support/Signals.cpp
@@ -26,15 +26,21 @@
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/StringSaver.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/Options.h"
 #include <vector>
 
-namespace llvm {
-
 //===----------------------------------------------------------------------===//
 //=== WARNING: Implementation here must contain only TRULY operating system
 //===          independent code.
 //===----------------------------------------------------------------------===//
 
+using namespace llvm;
+
+static cl::opt<bool>
+    DisableSymbolication("disable-symbolication",
+                         cl::desc("Disable symbolizing crash backtraces."),
+                         cl::init(false), cl::Hidden);
+
 static ManagedStatic<std::vector<std::pair<void (*)(void *), void *>>>
     CallBacksToRun;
 void sys::RunSignalHandlers() {
@@ -44,9 +50,6 @@
     I.first(I.second);
   CallBacksToRun->clear();
 }
-}
-
-using namespace llvm;
 
 static bool findModulesAndOffsets(void **StackTrace, int Depth,
                                   const char **Modules, intptr_t *Offsets,
@@ -70,6 +73,9 @@
 static bool printSymbolizedStackTrace(StringRef Argv0,
                                       void **StackTrace, int Depth,
                                       llvm::raw_ostream &OS) {
+  if (DisableSymbolication)
+    return false;
+
   // Don't recursively invoke the llvm-symbolizer binary.
   if (Argv0.find("llvm-symbolizer") != std::string::npos)
     return false;
Index: tools/bugpoint/OptimizerDriver.cpp
===================================================================
--- tools/bugpoint/OptimizerDriver.cpp
+++ tools/bugpoint/OptimizerDriver.cpp
@@ -202,6 +202,7 @@
   } else
     Args.push_back(tool.c_str());
 
+  Args.push_back("-disable-symbolication");
   Args.push_back("-o");
   Args.push_back(OutputFilename.c_str());
   for (unsigned i = 0, e = OptArgs.size(); i != e; ++i)
Index: tools/bugpoint/ToolRunner.h
===================================================================
--- tools/bugpoint/ToolRunner.h
+++ tools/bugpoint/ToolRunner.h
@@ -28,6 +28,7 @@
 namespace llvm {
 
 extern cl::opt<bool> SaveTemps;
+extern cl::opt<bool> EnableSymbolizer;
 extern Triple TargetTriple;
 
 class LLC;
Index: tools/bugpoint/ToolRunner.cpp
===================================================================
--- tools/bugpoint/ToolRunner.cpp
+++ tools/bugpoint/ToolRunner.cpp
@@ -29,6 +29,10 @@
 namespace llvm {
 cl::opt<bool> SaveTemps("save-temps", cl::init(false),
                         cl::desc("Save temporary files"));
+cl::opt<bool> EnableSymbolizer(
+    "enable-symbolizer", cl::init(false),
+    cl::desc(
+        "Enable symbolized backtraces on crashes of processes under test"));
 }
 
 namespace {
@@ -59,7 +63,8 @@
                                  unsigned MemoryLimit = 0,
                                  std::string *ErrMsg = nullptr) {
   const StringRef *Redirects[3] = {&StdInFile, &StdOutFile, &StdErrFile};
-  return sys::ExecuteAndWait(ProgramPath, Args, nullptr, Redirects, NumSeconds,
+  std::vector<const char*> Env = {"LLVM_DISABLE_SYMBOLICATION"};
+  return sys::ExecuteAndWait(ProgramPath, Args, Env.data(), Redirects, NumSeconds,
                              MemoryLimit, ErrMsg);
 }
 
@@ -77,8 +82,10 @@
                                          unsigned MemoryLimit = 0) {
   const StringRef *Redirects[3] = {&StdInFile, &StdOutFile, &StdErrFile};
 
+  std::vector<const char*> Env = {"LLVM_DISABLE_SYMBOLICATION"};
+
   // Run the program remotely with the remote client
-  int ReturnCode = sys::ExecuteAndWait(RemoteClientPath, Args, nullptr,
+  int ReturnCode = sys::ExecuteAndWait(RemoteClientPath, Args, Env.data(),
                                        Redirects, NumSeconds, MemoryLimit);
 
   // Has the remote client fail?