diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4679185573..56f0d0e1e3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -359,7 +359,7 @@ endif()
 if(MSVC)
     set(EXE_CFLAGS "${EXE_CFLAGS}")
 else()
-    set(EXE_CFLAGS "${EXE_CFLAGS} -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -D_GNU_SOURCE -fvisibility-inlines-hidden -fno-exceptions -fno-rtti -Werror=type-limits -Wno-missing-braces")
+    set(EXE_CFLAGS "${EXE_CFLAGS} -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -D_GNU_SOURCE -fvisibility-inlines-hidden -fno-exceptions -fno-rtti -Werror=type-limits -Wno-missing-braces -Wno-comment")
     if(MINGW)
         set(EXE_CFLAGS "${EXE_CFLAGS} -Wno-format")
     endif()
diff --git a/src/zig_clang_cc1_main.cpp b/src/zig_clang_cc1_main.cpp
index 6d1a67f2a4..0872015e0a 100644
--- a/src/zig_clang_cc1_main.cpp
+++ b/src/zig_clang_cc1_main.cpp
@@ -177,7 +177,7 @@ static int PrintSupportedCPUs(std::string TargetStr) {
   // the target machine will handle the mcpu printing
   llvm::TargetOptions Options;
   std::unique_ptr<llvm::TargetMachine> TheTargetMachine(
-      TheTarget->createTargetMachine(TargetStr, "", "+cpuHelp", Options, None));
+      TheTarget->createTargetMachine(TargetStr, "", "+cpuhelp", Options, None));
   return 0;
 }
 
@@ -203,8 +203,8 @@ int cc1_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
   IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
   TextDiagnosticBuffer *DiagsBuffer = new TextDiagnosticBuffer;
   DiagnosticsEngine Diags(DiagID, &*DiagOpts, DiagsBuffer);
-  bool Success =
-      CompilerInvocation::CreateFromArgs(Clang->getInvocation(), Argv, Diags);
+  bool Success = CompilerInvocation::CreateFromArgs(Clang->getInvocation(),
+                                                    Argv, Diags, Argv0);
 
   if (Clang->getFrontendOpts().TimeTrace) {
     llvm::timeTraceProfilerInitialize(
@@ -259,6 +259,7 @@ int cc1_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
       // FIXME(ibiryukov): make profilerOutput flush in destructor instead.
       profilerOutput->flush();
       llvm::timeTraceProfilerCleanup();
+      Clang->clearOutputFiles(false);
     }
   }
 
diff --git a/src/zig_clang_cc1as_main.cpp b/src/zig_clang_cc1as_main.cpp
index e1041f91bf..77b99b2013 100644
--- a/src/zig_clang_cc1as_main.cpp
+++ b/src/zig_clang_cc1as_main.cpp
@@ -207,7 +207,7 @@ bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
 
   // Target Options
   Opts.Triple = llvm::Triple::normalize(Args.getLastArgValue(OPT_triple));
-  Opts.CPU = Args.getLastArgValue(OPT_target_cpu);
+  Opts.CPU = std::string(Args.getLastArgValue(OPT_target_cpu));
   Opts.Features = Args.getAllArgValues(OPT_target_feature);
 
   // Use the default target triple if unspecified.
@@ -238,13 +238,19 @@ bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
 
   Opts.RelaxELFRelocations = Args.hasArg(OPT_mrelax_relocations);
   Opts.DwarfVersion = getLastArgIntValue(Args, OPT_dwarf_version_EQ, 2, Diags);
-  Opts.DwarfDebugFlags = Args.getLastArgValue(OPT_dwarf_debug_flags);
-  Opts.DwarfDebugProducer = Args.getLastArgValue(OPT_dwarf_debug_producer);
-  Opts.DebugCompilationDir = Args.getLastArgValue(OPT_fdebug_compilation_dir);
-  Opts.MainFileName = Args.getLastArgValue(OPT_main_file_name);
+  Opts.DwarfDebugFlags =
+      std::string(Args.getLastArgValue(OPT_dwarf_debug_flags));
+  Opts.DwarfDebugProducer =
+      std::string(Args.getLastArgValue(OPT_dwarf_debug_producer));
+  Opts.DebugCompilationDir =
+      std::string(Args.getLastArgValue(OPT_fdebug_compilation_dir));
+  Opts.MainFileName = std::string(Args.getLastArgValue(OPT_main_file_name));
 
-  for (const auto &Arg : Args.getAllArgValues(OPT_fdebug_prefix_map_EQ))
-    Opts.DebugPrefixMap.insert(StringRef(Arg).split('='));
+  for (const auto &Arg : Args.getAllArgValues(OPT_fdebug_prefix_map_EQ)) {
+    auto Split = StringRef(Arg).split('=');
+    Opts.DebugPrefixMap.insert(
+        {std::string(Split.first), std::string(Split.second)});
+  }
 
   // Frontend Options
   if (Args.hasArg(OPT_INPUT)) {
@@ -260,8 +266,9 @@ bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
     }
   }
   Opts.LLVMArgs = Args.getAllArgValues(OPT_mllvm);
-  Opts.OutputPath = Args.getLastArgValue(OPT_o);
-  Opts.SplitDwarfOutput = Args.getLastArgValue(OPT_split_dwarf_output);
+  Opts.OutputPath = std::string(Args.getLastArgValue(OPT_o));
+  Opts.SplitDwarfOutput =
+      std::string(Args.getLastArgValue(OPT_split_dwarf_output));
   if (Arg *A = Args.getLastArg(OPT_filetype)) {
     StringRef Name = A->getValue();
     unsigned OutputType = StringSwitch<unsigned>(Name)
@@ -289,8 +296,9 @@ bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
   Opts.NoExecStack = Args.hasArg(OPT_mno_exec_stack);
   Opts.FatalWarnings = Args.hasArg(OPT_massembler_fatal_warnings);
   Opts.NoWarn = Args.hasArg(OPT_massembler_no_warn);
-  Opts.RelocationModel = Args.getLastArgValue(OPT_mrelocation_model, "pic");
-  Opts.TargetABI = Args.getLastArgValue(OPT_target_abi);
+  Opts.RelocationModel =
+      std::string(Args.getLastArgValue(OPT_mrelocation_model, "pic"));
+  Opts.TargetABI = std::string(Args.getLastArgValue(OPT_target_abi));
   Opts.IncrementalLinkerCompatible =
       Args.hasArg(OPT_mincremental_linker_compatible);
   Opts.SymbolDefs = Args.getAllArgValues(OPT_defsym);
@@ -421,12 +429,7 @@ static bool ExecuteAssembler(AssemblerInvocation &Opts,
                             SrcMgr.getMemoryBuffer(BufferIndex)->getBuffer());
 
   // Build up the feature string from the target feature list.
-  std::string FS;
-  if (!Opts.Features.empty()) {
-    FS = Opts.Features[0];
-    for (unsigned i = 1, e = Opts.Features.size(); i != e; ++i)
-      FS += "," + Opts.Features[i];
-  }
+  std::string FS = llvm::join(Opts.Features, ",");
 
   std::unique_ptr<MCStreamer> Str;
 
@@ -490,7 +493,7 @@ static bool ExecuteAssembler(AssemblerInvocation &Opts,
     MCSection *AsmLabel = Ctx.getMachOSection(
         "__LLVM", "__asm", MachO::S_REGULAR, 4, SectionKind::getReadOnly());
     Str.get()->SwitchSection(AsmLabel);
-    Str.get()->EmitZeros(1);
+    Str.get()->emitZeros(1);
   }
 
   // Assembly to object compilation should leverage assembly info.
diff --git a/src/zig_clang_driver.cpp b/src/zig_clang_driver.cpp
index a3150022b3..fbe407a06c 100644
--- a/src/zig_clang_driver.cpp
+++ b/src/zig_clang_driver.cpp
@@ -30,6 +30,7 @@
 #include "llvm/Option/ArgList.h"
 #include "llvm/Option/OptTable.h"
 #include "llvm/Option/Option.h"
+#include "llvm/Support/BuryPointer.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/CrashRecoveryContext.h"
 #include "llvm/Support/ErrorHandling.h"
@@ -37,6 +38,7 @@
 #include "llvm/Support/Host.h"
 #include "llvm/Support/InitLLVM.h"
 #include "llvm/Support/Path.h"
+#include "llvm/Support/PrettyStackTrace.h"
 #include "llvm/Support/Process.h"
 #include "llvm/Support/Program.h"
 #include "llvm/Support/Regex.h"
@@ -60,7 +62,7 @@ std::string GetExecutablePath(const char *Argv0, bool CanonicalPrefixes) {
       if (llvm::ErrorOr<std::string> P =
               llvm::sys::findProgramByName(ExecutablePath))
         ExecutablePath = *P;
-    return ExecutablePath.str();
+    return std::string(ExecutablePath.str());
   }
 
   // This just needs to be some symbol in the binary; C++ doesn't
@@ -71,7 +73,7 @@ std::string GetExecutablePath(const char *Argv0, bool CanonicalPrefixes) {
 
 static const char *GetStableCStr(std::set<std::string> &SavedStrings,
                                  StringRef S) {
-  return SavedStrings.insert(S).first->c_str();
+  return SavedStrings.insert(std::string(S)).first->c_str();
 }
 
 /// ApplyQAOverride - Apply a list of edits to the input argument lists.
@@ -263,7 +265,7 @@ static void FixupDiagPrefixExeName(TextDiagnosticPrinter *DiagClient,
   StringRef ExeBasename(llvm::sys::path::stem(Path));
   if (ExeBasename.equals_lower("cl"))
     ExeBasename = "clang-cl";
-  DiagClient->setPrefix(ExeBasename);
+  DiagClient->setPrefix(std::string(ExeBasename));
 }
 
 // This lets us create the DiagnosticsEngine with a properly-filled-out
@@ -323,7 +325,7 @@ static int ExecuteCC1Tool(SmallVectorImpl<const char *> &ArgV) {
   StringRef Tool = ArgV[1];
   void *GetExecutablePathVP = (void *)(intptr_t)GetExecutablePath;
   if (Tool == "-cc1")
-    return cc1_main(makeArrayRef(ArgV).slice(2), ArgV[0], GetExecutablePathVP);
+    return cc1_main(makeArrayRef(ArgV).slice(1), ArgV[0], GetExecutablePathVP);
   if (Tool == "-cc1as")
     return cc1as_main(makeArrayRef(ArgV).slice(2), ArgV[0],
                       GetExecutablePathVP);
@@ -337,6 +339,9 @@ extern "C" int ZigClang_main(int argc_, const char **argv_);
 int ZigClang_main(int argc_, const char **argv_) {
   noteBottomOfStack();
   llvm::InitLLVM X(argc_, argv_);
+  llvm::setBugReportMsg("PLEASE submit a bug report to " BUG_REPORT_URL
+                        " and include the crash backtrace, preprocessed "
+                        "source, and associated run script.\n");
   size_t argv_offset = (strcmp(argv_[1], "-cc1") == 0 || strcmp(argv_[1], "-cc1as") == 0) ? 0 : 1;
   SmallVector<const char *, 256> argv(argv_ + argv_offset, argv_ + argc_);
 
@@ -488,6 +493,7 @@ int ZigClang_main(int argc_, const char **argv_) {
 
   std::unique_ptr<Compilation> C(TheDriver.BuildCompilation(argv));
   int Res = 1;
+  bool IsCrash = false;
   if (C && !C->containsError()) {
     SmallVector<std::pair<int, const Command *>, 4> FailingCommands;
     Res = TheDriver.ExecuteCompilation(*C, FailingCommands);
@@ -502,6 +508,11 @@ int ZigClang_main(int argc_, const char **argv_) {
       for (const auto &J : C->getJobs())
         if (const Command *C = dyn_cast<Command>(&J))
           FailingCommands.push_back(std::make_pair(-1, C));
+
+      // Print the bug report message that would be printed if we did actually
+      // crash, but only if we're crashing due to FORCE_CLANG_DIAGNOSTICS_CRASH.
+      if (::getenv("FORCE_CLANG_DIAGNOSTICS_CRASH"))
+        llvm::dbgs() << llvm::getBugReportMsg();
     }
 
     for (const auto &P : FailingCommands) {
@@ -514,11 +525,11 @@ int ZigClang_main(int argc_, const char **argv_) {
       // If result status is 70, then the driver command reported a fatal error.
       // On Windows, abort will return an exit code of 3.  In these cases,
       // generate additional diagnostic information if possible.
-      bool DiagnoseCrash = CommandRes < 0 || CommandRes == 70;
+      IsCrash = CommandRes < 0 || CommandRes == 70;
 #ifdef _WIN32
-      DiagnoseCrash |= CommandRes == 3;
+      IsCrash |= CommandRes == 3;
 #endif
-      if (DiagnoseCrash) {
+      if (IsCrash) {
         TheDriver.generateCompilationDiagnostics(*C, *FailingCommand);
         break;
       }
@@ -527,10 +538,16 @@ int ZigClang_main(int argc_, const char **argv_) {
 
   Diags.getClient()->finish();
 
-  // If any timers were active but haven't been destroyed yet, print their
-  // results now.  This happens in -disable-free mode.
-  llvm::TimerGroup::printAll(llvm::errs());
-  llvm::TimerGroup::clearAll();
+  if (!UseNewCC1Process && IsCrash) {
+    // When crashing in -fintegrated-cc1 mode, bury the timer pointers, because
+    // the internal linked list might point to already released stack frames.
+    llvm::BuryPointer(llvm::TimerGroup::aquireDefaultGroup());
+  } else {
+    // If any timers were active but haven't been destroyed yet, print their
+    // results now.  This happens in -disable-free mode.
+    llvm::TimerGroup::printAll(llvm::errs());
+    llvm::TimerGroup::clearAll();
+  }
 
 #ifdef _WIN32
   // Exit status should not be negative on Win32, unless abnormal termination.