Force sequential parsing when threads=0.

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 264 matching lines @@
     Str << "|Rel=" << Pool->Relocatables.size();
     Str << "|ExtRel=" << Pool->ExternRelocatables.size();
   }
   Str << "\n";
 }
 
 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(), OptQ(/*Sequential=*/Flags.isSequential(),
-                           /*MaxSize=*/
-                           (Flags.getParseParallel() && Flags.getBuildOnRead())
-                               ? MaxOptQSize
-                               : Flags.getNumTranslationThreads()),
+      ObjectWriter(),
+      OptQ(/*Sequential=*/Flags.isSequential(),
+           /*MaxSize=*/
+           Flags.isParseParallel() ? MaxOptQSize
+                                   : Flags.getNumTranslationThreads()),
       // EmitQ is allowed unlimited size.
       EmitQ(/*Sequential=*/Flags.isSequential()),
       DataLowering(TargetDataLowering::createLowering(this)) {
   assert(OsDump && "OsDump is not defined for GlobalContext");
   assert(OsEmit && "OsEmit is not defined for GlobalContext");
   assert(OsError && "OsError is not defined for GlobalContext");
   // Make sure thread_local fields are properly initialized before any
   // accesses are made.  Do this here instead of at the start of
   // main() so that all clients (e.g. unit tests) can benefit for
   // free.
@@ skipping 698 matching lines @@
   Ctx = Func->getContext();
   Active =
       Func->getFocusedTiming() || Ctx->getFlags().getSubzeroTimingEnabled();
   if (Active)
     Ctx->pushTimer(ID, StackID);
 }
 
 ICE_TLS_DEFINE_FIELD(GlobalContext::ThreadContext *, GlobalContext, TLS);
 
 } // end of namespace Ice