Subzero: Fixed deadlock with _start but no globals

src/IceGlobalContext.cpp

 //===- subzero/src/IceGlobalContext.cpp - Global context defs -------------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 280 matching lines @@
 
 namespace {
 
 // By default, wake up the main parser thread when the OptQ gets half empty.
 static constexpr size_t DefaultOptQWakeupSize = GlobalContext::MaxOptQSize >> 1;
 
 } // end of anonymous namespace
 
 GlobalContext::GlobalContext(Ostream *OsDump, Ostream *OsEmit, Ostream *OsError,
                              ELFStreamer *ELFStr)
-    : Strings(new StringPool()), ConstPool(new ConstantPool()), ErrorStatus(),
-      StrDump(OsDump), StrEmit(OsEmit), StrError(OsError), IntrinsicsInfo(this),
-      ObjectWriter(),
+    : GlobalsReceived(false), Strings(new StringPool()),
+      ConstPool(new ConstantPool()), ErrorStatus(), StrDump(OsDump),
+      StrEmit(OsEmit), StrError(OsError), IntrinsicsInfo(this), ObjectWriter(),
       OptQWakeupSize(std::max(DefaultOptQWakeupSize,
                               size_t(getFlags().getNumTranslationThreads()))),
       OptQ(/*Sequential=*/getFlags().isSequential(),
            /*MaxSize=*/
            getFlags().isParseParallel()
                ? MaxOptQSize
                : getFlags().getNumTranslationThreads()),
       // EmitQ is allowed unlimited size.
       EmitQ(/*Sequential=*/getFlags().isSequential()),
       DataLowering(TargetDataLowering::createLowering(this)) {
@@ skipping 727 matching lines @@
 void TimerMarker::pushCfg(const Cfg *Func) {
   Ctx = Func->getContext();
   Active = Func->getFocusedTiming() || getFlags().getSubzeroTimingEnabled();
   if (Active)
     Ctx->pushTimer(ID, StackID);
 }
 
 ICE_TLS_DEFINE_FIELD(GlobalContext::ThreadContext *, GlobalContext, TLS);
 
 } // end of namespace Ice