Revert changes from the nested lambdas commit till i figure out 
why the buildbots are failing.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191876 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaTemplateInstantiate.cpp b/lib/Sema/SemaTemplateInstantiate.cpp
index 29481d6..32111ba 100644
--- a/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/lib/Sema/SemaTemplateInstantiate.cpp
@@ -14,7 +14,6 @@
 #include "TreeTransform.h"
 #include "clang/AST/ASTConsumer.h"
 #include "clang/AST/ASTContext.h"
-#include "clang/AST/ASTLambda.h"
 #include "clang/AST/DeclTemplate.h"
 #include "clang/AST/Expr.h"
 #include "clang/Basic/LangOptions.h"
@@ -131,11 +130,6 @@
         assert(Function->getPrimaryTemplate() && "No function template?");
         if (Function->getPrimaryTemplate()->isMemberSpecialization())
           break;
-
-        // If this function is a generic lambda specialization, we are done.
-        if (isGenericLambdaCallOperatorSpecialization(Function))
-          break;
-
       } else if (FunctionTemplateDecl *FunTmpl
                                    = Function->getDescribedFunctionTemplate()) {
         // Add the "injected" template arguments.
@@ -917,56 +911,13 @@
     }
 
     ExprResult TransformLambdaScope(LambdaExpr *E,
-                                    CXXMethodDecl *NewCallOperator) {
-      // If a lambda is undergoing transformation for instance in the
-      // call to foo('a') below:
-      //  template<class T> void foo(T t) {
-      //    auto L1 = [](T a) { return a; };

-      //    auto L2 = [](char b) { return b; };
-      //    auto L3 = [](auto c) { return c; };
-      //  }
-      // The AST nodes of the OldCallOperators within the primary template foo
-      // are connected to the NewCallOperators within the specialization of foo.
-      //  - In the case of L1 and L2 we set the NewCallOperator to be considered
-      //    an instantiation of the OldCallOperator.
-      //  - In the generic lambda case, we set the NewTemplate to be considered
-      //    an "instantiation" of the OldTemplate.
-      // See the documentation and use of get/setInstantiationOfMemberFunction
-      // and get/setInstantiatedFromMemberTemplate to appreciate the relevance
-      // of creating these links. 
-      // And so it goes on and on with nested generic lambdas.
-      CXXMethodDecl *const OldCallOperator = E->getCallOperator();
-      FunctionTemplateDecl *const NewCallOperatorTemplate = 
-          NewCallOperator->getDescribedFunctionTemplate();
-      FunctionTemplateDecl *const OldCallOperatorTemplate = 
-          OldCallOperator->getDescribedFunctionTemplate();
+                                    CXXMethodDecl *CallOperator) {
+      CallOperator->setInstantiationOfMemberFunction(E->getCallOperator(),
+                                                     TSK_ImplicitInstantiation);
+      return TreeTransform<TemplateInstantiator>::
+         TransformLambdaScope(E, CallOperator);
+    }
 
-      if (!NewCallOperatorTemplate)
-        NewCallOperator->setInstantiationOfMemberFunction(OldCallOperator,
-                                                    TSK_ImplicitInstantiation);
-      else {
-        NewCallOperatorTemplate->setInstantiatedFromMemberTemplate(
-                                                      OldCallOperatorTemplate);
-        // Set this as a specialization so we don't go digging into the 
-        // OldCallOperatorTemplate when retrieving the 
-        // 'FunctionDecl::getTemplateInstantiationPattern()' 
-        NewCallOperatorTemplate->setMemberSpecialization();
-      }
-      return inherited::TransformLambdaScope(E, NewCallOperator);
-    }
-    TemplateParameterList *TransformTemplateParameterList(

-                              TemplateParameterList *OrigTPL)  {
-      TemplateParameterList *NewTPL = 0;
-      if (OrigTPL) {
-        if (!OrigTPL->size()) return OrigTPL; // size 0, do nothing
-         
-        DeclContext *Owner = OrigTPL->getParam(0)->getDeclContext();
-        TemplateDeclInstantiator  DeclInstantiator(getSema(), 
-                          /* DeclContext *Owner */ Owner, TemplateArgs);
-        NewTPL = DeclInstantiator.SubstTemplateParams(OrigTPL);
-      }
-      return NewTPL;  
-    }
   private:
     ExprResult transformNonTypeTemplateParmRef(NonTypeTemplateParmDecl *parm,
                                                SourceLocation loc,
diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 359fb73..35f3616 100644
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -4171,30 +4171,6 @@
 NamedDecl *Sema::FindInstantiatedDecl(SourceLocation Loc, NamedDecl *D,
                           const MultiLevelTemplateArgumentList &TemplateArgs) {
   DeclContext *ParentDC = D->getDeclContext();
-
-  // If we have a parameter from a non-dependent context with a non-dependent
-  // type it obviously can not be mapped to a different instantiated decl.
-  // Consider the code below, with explicit return types, when N gets
-  // specialized ...:
-  // template<class T> void fooT(T t) {
-  //   auto L = [](auto a) -> void { 
-  //     auto M = [](char b) -> void {
-  //       auto N = [](auto c) -> void {
-  //         int x = sizeof(a) + sizeof(b) +
-  //                 sizeof(c);
-  //       };  
-  //       N('a');
-  //     };    
-  //   };
-  //   L(3.14);
-  // }
-  // fooT('a'); 
-  // ... without this check below, findInstantiationOf fails with
-  // an assertion violation.
-  if (isa<ParmVarDecl>(D) && !ParentDC->isDependentContext() &&
-      !cast<ParmVarDecl>(D)->getType()->isInstantiationDependentType())
-    return D;
-
   if (isa<ParmVarDecl>(D) || isa<NonTypeTemplateParmDecl>(D) ||
       isa<TemplateTypeParmDecl>(D) || isa<TemplateTemplateParmDecl>(D) ||
       (ParentDC->isFunctionOrMethod() && ParentDC->isDependentContext()) ||
diff --git a/lib/Sema/TreeTransform.h b/lib/Sema/TreeTransform.h
index bec956b..977d013 100644
--- a/lib/Sema/TreeTransform.h
+++ b/lib/Sema/TreeTransform.h
@@ -594,11 +594,6 @@
   /// \brief Transform the captures and body of a lambda expression.
   ExprResult TransformLambdaScope(LambdaExpr *E, CXXMethodDecl *CallOperator);
 
-  TemplateParameterList *TransformTemplateParameterList(
-        TemplateParameterList *TPL) {
-    return TPL;
-  }
-
   ExprResult TransformAddressOfOperand(Expr *E);
   ExprResult TransformDependentScopeDeclRefExpr(DependentScopeDeclRefExpr *E,
                                                 bool IsAddressOfOperand);
@@ -4578,19 +4573,6 @@
 QualType TreeTransform<Derived>::TransformDecltypeType(TypeLocBuilder &TLB,
                                                        DecltypeTypeLoc TL) {
   const DecltypeType *T = TL.getTypePtr();
-  // Don't transform a decltype construct that has already been transformed 
-  // into a non-dependent type.
-  // Allows the following to compile:
-  // auto L = [](auto a) {
-  //   return [](auto b) ->decltype(a) {
-  //     return b;
-  //  };
-  //};  
-  if (!T->isInstantiationDependentType()) {
-    DecltypeTypeLoc NewTL = TLB.push<DecltypeTypeLoc>(TL.getType());
-    NewTL.setNameLoc(TL.getNameLoc());
-    return NewTL.getType();
-  }
 
   // decltype expressions are not potentially evaluated contexts
   EnterExpressionEvaluationContext Unevaluated(SemaRef, Sema::Unevaluated, 0,
@@ -8302,27 +8284,24 @@
 ExprResult
 TreeTransform<Derived>::TransformLambdaExpr(LambdaExpr *E) {
  
-  getSema().PushLambdaScope();
-  LambdaScopeInfo *LSI = getSema().getCurLambda();
-  TemplateParameterList *const OrigTPL = E->getTemplateParameterList();
-  TemplateParameterList *NewTPL = 0;
-  // Transform the template parameters, and add them to the 
-  // current instantiation scope.
-  if (OrigTPL) {
-      NewTPL = getDerived().TransformTemplateParameterList(OrigTPL);
+  // FIXME: Implement nested generic lambda transformations.
+  if (E->isGenericLambda()) {
+    getSema().Diag(E->getIntroducerRange().getBegin(), 
+      diag::err_glambda_not_fully_implemented) 
+      << " template transformation of generic lambdas not implemented yet";
+    return ExprError();
   }
-  LSI->GLTemplateParameterList = NewTPL;
-   // Transform the type of the lambda parameters and start the definition of
-   // the lambda itself.
-  TypeSourceInfo *OldCallOpTSI = E->getCallOperator()->getTypeSourceInfo(); 
-  TypeSourceInfo *NewCallOpTSI = TransformType(OldCallOpTSI);
-  if (!NewCallOpTSI)
+  // Transform the type of the lambda parameters and start the definition of
+  // the lambda itself.
+  TypeSourceInfo *MethodTy
+    = TransformType(E->getCallOperator()->getTypeSourceInfo());
+  if (!MethodTy)
     return ExprError();
 
   // Create the local class that will describe the lambda.
   CXXRecordDecl *Class
     = getSema().createLambdaClosureType(E->getIntroducerRange(),
-                                        NewCallOpTSI,
+                                        MethodTy,
                                         /*KnownDependent=*/false);
   getDerived().transformedLocalDecl(E->getLambdaClass(), Class);
 
@@ -8334,49 +8313,19 @@
         E->getCallOperator()->param_size(),
         0, ParamTypes, &Params))
     return ExprError();
-
+  getSema().PushLambdaScope();
+  LambdaScopeInfo *LSI = getSema().getCurLambda();
+  // TODO: Fix for nested lambdas
+  LSI->GLTemplateParameterList = 0;
   // Build the call operator.
-  CXXMethodDecl *NewCallOperator
+  CXXMethodDecl *CallOperator
     = getSema().startLambdaDefinition(Class, E->getIntroducerRange(),
-                                      NewCallOpTSI,
+                                      MethodTy,
                                       E->getCallOperator()->getLocEnd(),
                                       Params);
-  LSI->CallOperator = NewCallOperator;
-  // Fix the Decl Contexts of the parameters within the call op function 
-  // prototype.
-  getDerived().transformAttrs(E->getCallOperator(), NewCallOperator);
-  
-  TypeLoc NewCallOpTL = NewCallOpTSI->getTypeLoc();
-  FunctionProtoTypeLoc NewFPTL = NewCallOpTL.castAs<FunctionProtoTypeLoc>();
-  ParmVarDecl **NewParamDeclArray = NewFPTL.getParmArray();
-  const unsigned NewNumArgs = NewFPTL.getNumArgs();
-  for (unsigned I = 0; I < NewNumArgs; ++I) {
-      NewParamDeclArray[I]->setOwningFunction(NewCallOperator);
-  }
-  // If this is a non-generic lambda, the parameters do not get added to the
-  // current instantiation scope, so add them.  This feels kludgey.
-  // Anyway, it allows the following to compile when the enclosing template
-  // is specialized and the entire lambda expression has to be
-  // transformed.  Without this FindInstantiatedDecl causes an assertion.
-  // template<class T> void foo(T t) {
-  //    auto L = [](auto a) { 
-  //      auto M = [](char b) { <-- note: non-generic lambda
-  //        auto N = [](auto c) {
-  //          int x = sizeof(a);        
-  //          x = sizeof(b); <-- specifically this line
-  //          x = sizeof(c);
-  //        };  
-  //      };    
-  //    };
-  //  }
-  //  foo('a');
-  //
-  if (!E->isGenericLambda()) {
-    for (unsigned I = 0; I < NewNumArgs; ++I)
-      SemaRef.CurrentInstantiationScope->InstantiatedLocal(
-                                   NewParamDeclArray[I], NewParamDeclArray[I]);
-  }
-  return getDerived().TransformLambdaScope(E, NewCallOperator);
+  getDerived().transformAttrs(E->getCallOperator(), CallOperator);
+
+  return getDerived().TransformLambdaScope(E, CallOperator);
 }
 
 template<typename Derived>