PNaCl Dynamic Linking: 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 3025 matching lines @@
 
 private:
   Ice::TimerMarker Timer;
   const char *getTableKind() const final { return "Module"; }
   void setValueName(NaClBcIndexSize_t Index, StringType &Name) final;
   void setBbName(NaClBcIndexSize_t Index, StringType &Name) final;
 };
 
 void ModuleValuesymtabParser::setValueName(NaClBcIndexSize_t Index,
                                            StringType &Name) {
-  Context->getGlobalDeclarationByID(Index)
-      ->setName(StringRef(Name.data(), Name.size()));
+  Ice::GlobalDeclaration *Decl = Context->getGlobalDeclarationByID(Index);
+  if (llvm::isa<Ice::VariableDeclaration>(Decl) &&
+      Decl->isPNaClABIExternalName(Name.str())) {
+    // Force linkage of (specific) Global Variables 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);
+  }
+
+  Decl->setName(StringRef(Name.data(), Name.size()));
 }
 
 void ModuleValuesymtabParser::setBbName(NaClBcIndexSize_t Index,
                                         StringType &Name) {
   reportUnableToAssign("Basic block", Index, Name);
 }
 
 bool ModuleParser::ParseBlock(unsigned BlockID) {
   switch (BlockID) {
   case naclbitc::BLOCKINFO_BLOCK_ID:
@@ skipping 144 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