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 458 matching lines @@
   // Gives Decl a name if it doesn't already have one. Prefix and NameIndex are
   // used to generate the name. NameIndex is automatically incremented if a new
   // name is created. DeclType is literal text describing the type of name
   // being created. Also generates warning if created names may conflict with
   // named declarations.
   void installDeclarationName(Ice::GlobalDeclaration *Decl,
                               const Ice::IceString &Prefix,
                               const char *DeclType,
                               NaClBcIndexSize_t &NameIndex) {
     if (Decl->hasName()) {
+      if (Decl->isPNaClABIExternalName()) {
+        // Force linkage to be external for the PNaCl ABI. PNaCl bitcode has a
+        // linkage field for Functions, but not for GlobalVariables (because the
+        // latter is not needed for pexes, so it has been removed).
+        Decl->setLinkage(llvm::GlobalValue::ExternalLinkage);

[Mark Seaborn, 2016/02/26 23:18:58]

It looks like you're doing this for functions, but that's not ideal -- you
should only do this for GlobalVariables.

+      }
       Translator.checkIfUnnamedNameSafe(Decl->getName(), DeclType, Prefix);
     } else {
       Decl->setName(Translator.createUnnamedName(Prefix, NameIndex));
       ++NameIndex;
     }
   }
 
   // Installs names for global variables without names.
   void installGlobalVarNames() {
     assert(VariableDeclarations);
@@ skipping 2716 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