Force __pnacl_pso_root to be an external declaration.

src/PNaClTranslator.cpp

 //===- subzero/src/PNaClTranslator.cpp - ICE from bitcode -----------------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 529 matching lines @@
         reportLinkageError("Function", *Func);
       Ice::Constant *C = getConstantSym(
           Func->getName(), Func->getSuppressMangling(), Func->isProto());
       ValueIDConstants.push_back(C);
     }
   }
 
   // Converts global variable declarations into constant value IDs.
   void createValueIDsForGlobalVars() {
     Ice::GlobalContext *Ctx = getTranslator().getContext();
-    for (const Ice::VariableDeclaration *Decl : *VariableDeclarations) {
-      if (!Decl->verifyLinkageCorrect(Ctx))
+    for (Ice::VariableDeclaration *Decl : *VariableDeclarations) {
+      if (!Decl->verifyLinkageCorrect(Ctx) && !Decl->forcePNaClABILinkage())
         reportLinkageError("Global", *Decl);
       Ice::Constant *C =
           getConstantSym(Decl->getName(), Decl->getSuppressMangling(),
                          !Decl->hasInitializer());
       ValueIDConstants.push_back(C);
     }
   }
 
   // Reports that type ID is undefined, or not of the WantedType.
   void reportBadTypeIDAs(NaClBcIndexSize_t ID, const ExtendedType *Ty,
@@ skipping 2643 matching lines @@
     raw_string_ostream StrBuf(Buffer);
     StrBuf << IRFilename << ": Does not contain a module!";
     llvm::report_fatal_error(StrBuf.str());
   }
   if (InputStreamFile.getBitcodeBytes().getExtent() % 4 != 0) {
     llvm::report_fatal_error("Bitcode stream should be a multiple of 4 bytes");
   }
 }
 
 } // end of namespace Ice