most of this is plumbing to get CompileOptions down into 
CodeGenModule.  Once there, add a new NoCommon option to
it and implement -fno-common.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@67735 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 92af03e..8a88051 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -11,12 +11,13 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "CGDebugInfo.h"
 #include "CodeGenModule.h"
+#include "CGDebugInfo.h"
 #include "CodeGenFunction.h"
 #include "CGCall.h"
 #include "CGObjCRuntime.h"
 #include "Mangle.h"
+#include "clang/Frontend/CompileOptions.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/DeclObjC.h"
 #include "clang/AST/DeclCXX.h"
@@ -31,10 +32,11 @@
 using namespace CodeGen;
 
 
-CodeGenModule::CodeGenModule(ASTContext &C, const LangOptions &LO,
+CodeGenModule::CodeGenModule(ASTContext &C, const CompileOptions &compileOpts,
                              llvm::Module &M, const llvm::TargetData &TD,
-                             Diagnostic &diags, bool GenerateDebugInfo)
-  : BlockModule(C, M, TD, Types, *this), Context(C), Features(LO), TheModule(M),
+                             Diagnostic &diags)
+  : BlockModule(C, M, TD, Types, *this), Context(C),
+    Features(C.getLangOptions()), CompileOpts(compileOpts), TheModule(M),
     TheTargetData(TD), Diags(diags), Types(C, M, TD), Runtime(0),
     MemCpyFn(0), MemMoveFn(0), MemSetFn(0), CFConstantStringClassRef(0) {
 
@@ -48,7 +50,7 @@
     Runtime = CreateMacObjCRuntime(*this);
 
   // If debug info generation is enabled, create the CGDebugInfo object.
-  DebugInfo = GenerateDebugInfo ? new CGDebugInfo(this) : 0;
+  DebugInfo = CompileOpts.DebugInfo ? new CGDebugInfo(this) : 0;
 }
 
 CodeGenModule::~CodeGenModule() {
@@ -767,7 +769,7 @@
     case VarDecl::Register:
       assert(0 && "Can't have auto or register globals");
     case VarDecl::None:
-      if (!D->getInit())
+      if (!D->getInit() && !CompileOpts.NoCommon)
         GV->setLinkage(llvm::GlobalVariable::CommonLinkage);
       else
         GV->setLinkage(llvm::GlobalVariable::ExternalLinkage);
diff --git a/lib/CodeGen/CodeGenModule.h b/lib/CodeGen/CodeGenModule.h
index a327748..228020c 100644
--- a/lib/CodeGen/CodeGenModule.h
+++ b/lib/CodeGen/CodeGenModule.h
@@ -14,15 +14,13 @@
 #ifndef CLANG_CODEGEN_CODEGENMODULE_H
 #define CLANG_CODEGEN_CODEGENMODULE_H
 
-#include "CodeGenTypes.h"
 #include "clang/AST/Attr.h"
+#include "CGBlocks.h"
+#include "CGCall.h"
+#include "CodeGenTypes.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringSet.h"
-
-#include "CGBlocks.h"
-#include "CGCall.h"
-
 #include <list>
 
 namespace llvm {
@@ -52,6 +50,7 @@
   class ValueDecl;
   class VarDecl;
   class LangOptions;
+  class CompileOptions;
   class Diagnostic;
   class AnnotateAttr;
 
@@ -71,6 +70,7 @@
 
   ASTContext &Context;
   const LangOptions &Features;
+  const CompileOptions &CompileOpts;
   llvm::Module &TheModule;
   const llvm::TargetData &TheTargetData;
   Diagnostic &Diags;
@@ -138,9 +138,8 @@
   /// strings. This value has type int * but is actually an Obj-C class pointer.
   llvm::Constant *CFConstantStringClassRef;
 public:
-  CodeGenModule(ASTContext &C, const LangOptions &Features, llvm::Module &M,
-                const llvm::TargetData &TD, Diagnostic &Diags,
-                bool GenerateDebugInfo);
+  CodeGenModule(ASTContext &C, const CompileOptions &CompileOpts,
+                llvm::Module &M, const llvm::TargetData &TD, Diagnostic &Diags);
 
   ~CodeGenModule();
 
diff --git a/lib/CodeGen/ModuleBuilder.cpp b/lib/CodeGen/ModuleBuilder.cpp
index 3e3f5e4..6c0b68b 100644
--- a/lib/CodeGen/ModuleBuilder.cpp
+++ b/lib/CodeGen/ModuleBuilder.cpp
@@ -13,20 +13,17 @@
 
 #include "clang/CodeGen/ModuleBuilder.h"
 #include "CodeGenModule.h"
+#include "clang/Frontend/CompileOptions.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/DeclObjC.h"
 #include "clang/AST/Expr.h"
-using namespace clang;
-
-//===----------------------------------------------------------------------===//
-// LLVM Emitter
-
 #include "clang/Basic/Diagnostic.h"
 #include "clang/Basic/TargetInfo.h"
 #include "llvm/Module.h"
 #include "llvm/Target/TargetData.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/ADT/OwningPtr.h"
+using namespace clang;
 
 
 namespace {
@@ -34,17 +31,14 @@
     Diagnostic &Diags;
     llvm::OwningPtr<const llvm::TargetData> TD;
     ASTContext *Ctx;
-    const LangOptions &Features;
-    bool GenerateDebugInfo;
+    const CompileOptions CompileOpts;  // Intentionally copied in.
   protected:
     llvm::OwningPtr<llvm::Module> M;
     llvm::OwningPtr<CodeGen::CodeGenModule> Builder;
   public:
-    CodeGeneratorImpl(Diagnostic &diags, const LangOptions &LO,
-                      const std::string& ModuleName,
-                      bool DebugInfoFlag)
-    : Diags(diags), Features(LO), GenerateDebugInfo(DebugInfoFlag),
-      M(new llvm::Module(ModuleName)) {}
+    CodeGeneratorImpl(Diagnostic &diags, const std::string& ModuleName,
+                      const CompileOptions &CO)
+      : Diags(diags), CompileOpts(CO), M(new llvm::Module(ModuleName)) {}
     
     virtual ~CodeGeneratorImpl() {}
     
@@ -62,8 +56,8 @@
       M->setTargetTriple(Ctx->Target.getTargetTriple());
       M->setDataLayout(Ctx->Target.getTargetDescription());
       TD.reset(new llvm::TargetData(Ctx->Target.getTargetDescription()));
-      Builder.reset(new CodeGen::CodeGenModule(Context, Features, *M, *TD,
-                                               Diags, GenerateDebugInfo));
+      Builder.reset(new CodeGen::CodeGenModule(Context, CompileOpts,
+                                               *M, *TD, Diags));
     }
     
     virtual void HandleTopLevelDecl(Decl *D) {
@@ -93,8 +87,7 @@
 }
 
 CodeGenerator *clang::CreateLLVMCodeGen(Diagnostic &Diags, 
-                                        const LangOptions &Features,
                                         const std::string& ModuleName,
-                                        bool GenerateDebugInfo) {
-  return new CodeGeneratorImpl(Diags, Features, ModuleName, GenerateDebugInfo);
+                                        const CompileOptions &CO) {
+  return new CodeGeneratorImpl(Diags, ModuleName, CO);
 }