Re: [PATCH] D19322: Concepts: Create space for requires-clause in TemplateParameterList; NFC

2016-07-14 Thread Richard Smith via cfe-commits 
rsmith accepted this revision.
This revision is now accepted and ready to land.


Comment at: lib/AST/ASTImporter.cpp:2253-2254
@@ +2252,4 @@
+  return nullptr;
+  }
+  else {
+ToRequiresClause = nullptr;

`else` on same line as `}` please.


https://reviews.llvm.org/D19322



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Re: [PATCH] D19322: Concepts: Create space for requires-clause in TemplateParameterList; NFC

2016-06-21 Thread Hubert Tong via cfe-commits 
hubert.reinterpretcast added a comment.

Ping.


http://reviews.llvm.org/D19322



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Re: [PATCH] D19322: Concepts: Create space for requires-clause in TemplateParameterList; NFC

2016-05-16 Thread Hubert Tong via cfe-commits 
hubert.reinterpretcast added a comment.

Ping (#2).


http://reviews.llvm.org/D19322



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Re: [PATCH] D19322: Concepts: Create space for requires-clause in TemplateParameterList; NFC

2016-05-13 Thread Hubert Tong via cfe-commits 
hubert.reinterpretcast updated this revision to Diff 57216.
hubert.reinterpretcast added a comment.

Set requires-clause when creating TemplateParameterLists; NFC

Removes the default argument for the requires-clause constraint expression in 
TemplateParameterList::Create.

An appropriate argument is supplied at the various call sites. Serialization 
changes will be left until the feature is otherwise complete so that the 
version number does not need to be bumped multiple times.


http://reviews.llvm.org/D19322

Files:
  include/clang/AST/DeclTemplate.h
  lib/AST/ASTContext.cpp
  lib/AST/ASTImporter.cpp
  lib/AST/DeclTemplate.cpp
  lib/Sema/SemaLambda.cpp
  lib/Sema/SemaTemplate.cpp
  lib/Sema/SemaTemplateDeduction.cpp
  lib/Sema/SemaTemplateInstantiateDecl.cpp
  lib/Serialization/ASTReader.cpp
  lib/Serialization/ASTWriter.cpp

Index: lib/Serialization/ASTWriter.cpp
===
--- lib/Serialization/ASTWriter.cpp
+++ lib/Serialization/ASTWriter.cpp
@@ -5359,6 +5359,7 @@
   AddSourceLocation(TemplateParams->getTemplateLoc());
   AddSourceLocation(TemplateParams->getLAngleLoc());
   AddSourceLocation(TemplateParams->getRAngleLoc());
+  // TODO: Concepts
   Record->push_back(TemplateParams->size());
   for (const auto &P : *TemplateParams)
 AddDeclRef(P);
Index: lib/Serialization/ASTReader.cpp
===
--- lib/Serialization/ASTReader.cpp
+++ lib/Serialization/ASTReader.cpp
@@ -7892,9 +7892,10 @@
   while (NumParams--)
 Params.push_back(ReadDeclAs(F, Record, Idx));
 
+  // TODO: Concepts
   TemplateParameterList* TemplateParams =
 TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc,
-  Params, RAngleLoc);
+  Params, RAngleLoc, nullptr);
   return TemplateParams;
 }
 
Index: lib/Sema/SemaTemplateInstantiateDecl.cpp
===
--- lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -2947,10 +2947,14 @@
   if (Invalid)
 return nullptr;
 
+  // Note: we substitute into associated constraints later
+  Expr *const UninstantiatedRequiresClause = L->getRequiresClause();
+
   TemplateParameterList *InstL
 = TemplateParameterList::Create(SemaRef.Context, L->getTemplateLoc(),
 L->getLAngleLoc(), Params,
-L->getRAngleLoc());
+L->getRAngleLoc(),
+UninstantiatedRequiresClause);
   return InstL;
 }
 
Index: lib/Sema/SemaTemplateDeduction.cpp
===
--- lib/Sema/SemaTemplateDeduction.cpp
+++ lib/Sema/SemaTemplateDeduction.cpp
@@ -4022,8 +4022,8 @@
  nullptr, false, false);
   QualType TemplArg = QualType(TemplParam->getTypeForDecl(), 0);
   NamedDecl *TemplParamPtr = TemplParam;
-  FixedSizeTemplateParameterListStorage<1> TemplateParamsSt(
-  Loc, Loc, TemplParamPtr, Loc);
+  FixedSizeTemplateParameterListStorage<1, false> TemplateParamsSt(
+  Loc, Loc, TemplParamPtr, Loc, nullptr);
 
   QualType FuncParam = SubstituteAutoTransform(*this, TemplArg).Apply(Type);
   assert(!FuncParam.isNull() &&
Index: lib/Sema/SemaTemplate.cpp
===
--- lib/Sema/SemaTemplate.cpp
+++ lib/Sema/SemaTemplate.cpp
@@ -831,11 +831,10 @@
   if (ExportLoc.isValid())
 Diag(ExportLoc, diag::warn_template_export_unsupported);
 
-  // FIXME: store RequiresClause
   return TemplateParameterList::Create(
   Context, TemplateLoc, LAngleLoc,
   llvm::makeArrayRef((NamedDecl *const *)Params.data(), Params.size()),
-  RAngleLoc);
+  RAngleLoc, RequiresClause);
 }
 
 static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) {
@@ -1953,7 +1952,7 @@
   // Fabricate an empty template parameter list for the invented header.
   return TemplateParameterList::Create(Context, SourceLocation(),
SourceLocation(), None,
-   SourceLocation());
+   SourceLocation(), nullptr);
 }
 
 return nullptr;
Index: lib/Sema/SemaLambda.cpp
===
--- lib/Sema/SemaLambda.cpp
+++ lib/Sema/SemaLambda.cpp
@@ -235,7 +235,7 @@
 /*Template kw loc*/ SourceLocation(), LAngleLoc,
 llvm::makeArrayRef((NamedDecl *const *)LSI->AutoTemplateParams.data(),
LSI->AutoTemplateParams.size()),
-RAngleLoc);
+RAngleLoc, nullptr);
   }
   return LSI->GLTemplateParameterList;
 }
Index: lib/AST/DeclTemplate.cpp
===
--- lib/AST/DeclTemplate.cpp
+++ lib/AST/DeclTe

Re: [PATCH] D19322: Concepts: Create space for requires-clause in TemplateParameterList; NFC

2016-05-09 Thread Hubert Tong via cfe-commits 
hubert.reinterpretcast added a comment.

Ping.


http://reviews.llvm.org/D19322



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Re: [PATCH] D19322: Concepts: Create space for requires-clause in TemplateParameterList; NFC

2016-05-02 Thread Hubert Tong via cfe-commits 
hubert.reinterpretcast marked 2 inline comments as done.
hubert.reinterpretcast added a comment.

@rsmith; I've addressed Faisal's comment. Please let me know if this patch (and 
http://reviews.llvm.org/D19770) is good to go. If it isn't ready yet, I'd like 
your opinion on http://reviews.llvm.org/D19770+http://reviews.llvm.org/D19771.


http://reviews.llvm.org/D19322



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Re: [PATCH] D19322: Concepts: Create space for requires-clause in TemplateParameterList; NFC

2016-05-02 Thread Hubert Tong via cfe-commits 
hubert.reinterpretcast updated this revision to Diff 55850.
hubert.reinterpretcast added a comment.

Address Faisal's comment; supercedes http://reviews.llvm.org/D19771

Replaces the custom FixedSizeTemplateParameterListStorage implementation with 
one that follows the interface provided by llvm::TrailingObjects.


http://reviews.llvm.org/D19322

Files:
  include/clang/AST/DeclTemplate.h
  lib/AST/DeclTemplate.cpp
  lib/Sema/SemaTemplateDeduction.cpp

Index: lib/Sema/SemaTemplateDeduction.cpp
===
--- lib/Sema/SemaTemplateDeduction.cpp
+++ lib/Sema/SemaTemplateDeduction.cpp
@@ -4022,8 +4022,8 @@
  nullptr, false, false);
   QualType TemplArg = QualType(TemplParam->getTypeForDecl(), 0);
   NamedDecl *TemplParamPtr = TemplParam;
-  FixedSizeTemplateParameterListStorage<1> TemplateParamsSt(
-  Loc, Loc, TemplParamPtr, Loc);
+  FixedSizeTemplateParameterListStorage<1, false> TemplateParamsSt(
+  Loc, Loc, TemplParamPtr, Loc, nullptr);
 
   QualType FuncParam = SubstituteAutoTransform(*this, TemplArg).Apply(Type);
   assert(!FuncParam.isNull() &&
Index: lib/AST/DeclTemplate.cpp
===
--- lib/AST/DeclTemplate.cpp
+++ lib/AST/DeclTemplate.cpp
@@ -31,9 +31,11 @@
 TemplateParameterList::TemplateParameterList(SourceLocation TemplateLoc,
  SourceLocation LAngleLoc,
  ArrayRef Params,
- SourceLocation RAngleLoc)
+ SourceLocation RAngleLoc,
+ Expr *RequiresClause)
   : TemplateLoc(TemplateLoc), LAngleLoc(LAngleLoc), RAngleLoc(RAngleLoc),
-NumParams(Params.size()), ContainsUnexpandedParameterPack(false) {
+NumParams(Params.size()), ContainsUnexpandedParameterPack(false),
+HasRequiresClause(static_cast(RequiresClause)) {
   assert(this->NumParams == NumParams && "Too many template parameters");
   for (unsigned Idx = 0; Idx < NumParams; ++Idx) {
 NamedDecl *P = Params[Idx];
@@ -52,15 +54,21 @@
   // template parameter list does too.
 }
   }
+  if (RequiresClause) {
+*getTrailingObjects() = RequiresClause;
+  }
 }
 
-TemplateParameterList *TemplateParameterList::Create(
-const ASTContext &C, SourceLocation TemplateLoc, SourceLocation LAngleLoc,
-ArrayRef Params, SourceLocation RAngleLoc) {
-  void *Mem = C.Allocate(totalSizeToAlloc(Params.size()),
+TemplateParameterList *
+TemplateParameterList::Create(const ASTContext &C, SourceLocation TemplateLoc,
+  SourceLocation LAngleLoc,
+  ArrayRef Params,
+  SourceLocation RAngleLoc, Expr *RequiresClause) {
+  void *Mem = C.Allocate(totalSizeToAlloc(
+ Params.size(), RequiresClause ? 1u : 0u),
  llvm::alignOf());
   return new (Mem) TemplateParameterList(TemplateLoc, LAngleLoc, Params,
- RAngleLoc);
+ RAngleLoc, RequiresClause);
 }
 
 unsigned TemplateParameterList::getMinRequiredArguments() const {
Index: include/clang/AST/DeclTemplate.h
===
--- include/clang/AST/DeclTemplate.h
+++ include/clang/AST/DeclTemplate.h
@@ -46,7 +46,8 @@
 /// \brief Stores a list of template parameters for a TemplateDecl and its
 /// derived classes.
 class TemplateParameterList final
-: private llvm::TrailingObjects {
+: private llvm::TrailingObjects {
 
   /// The location of the 'template' keyword.
   SourceLocation TemplateLoc;
@@ -56,26 +57,36 @@
 
   /// The number of template parameters in this template
   /// parameter list.
-  unsigned NumParams : 31;
+  unsigned NumParams : 30;
 
   /// Whether this template parameter list contains an unexpanded parameter
   /// pack.
   unsigned ContainsUnexpandedParameterPack : 1;
 
+  /// Whether this template parameter list has an associated requires-clause
+  unsigned HasRequiresClause : 1;
+
 protected:
   size_t numTrailingObjects(OverloadToken) const {
 return NumParams;
   }
 
+  size_t numTrailingObjects(OverloadToken) const {
+return HasRequiresClause;
+  }
+
   TemplateParameterList(SourceLocation TemplateLoc, SourceLocation LAngleLoc,
-ArrayRef Params, SourceLocation RAngleLoc);
+ArrayRef Params, SourceLocation RAngleLoc,
+Expr *RequiresClause);
 
 public:
+  // FIXME: remove default argument for RequiresClause
   static TemplateParameterList *Create(const ASTContext &C,
SourceLocation TemplateLoc,
SourceLocation LAngleLoc,
ArrayRef Params,
-

Re: [PATCH] D19322: Concepts: Create space for requires-clause in TemplateParameterList; NFC

2016-04-29 Thread Hubert Tong via cfe-commits 
hubert.reinterpretcast added inline comments.


Comment at: include/clang/AST/DeclTemplate.h:175
@@ -152,2 +174,3 @@
+  Expr *RequiresClause;
 
 public:

faisalv wrote:
> Yuk - this entire guy (FizedSizeTemplateParameterListStorage) seems quite 
> fragile (dependent on object layout) - are the gains (in the single use below 
> during auto-type deduction) in preformance really worth the introduction of 
> this fragility/ugliness? 
> Unless there is a clear win from this strategy, I think i'd favor (perhaps in 
> a later patch) - either just removing this structure and using TPL for the 
> use-case in auto-type below, or using placement new and creating the stack 
> TPL on a stack unsigned char array?
> Thoughts?
> 
I don't like the class here either; however, I would not like to introduce heap 
allocation just to remove it. placement-new is certainly part of the solution. 
I think that `TrailingObjects` should have an alias for a type that can be used 
as aligned storage (templated in the style of `totalSizeToAlloc`). I would like 
to keep that endeavour to a separate patch though.


http://reviews.llvm.org/D19322



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Re: [PATCH] D19322: Concepts: Create space for requires-clause in TemplateParameterList; NFC

2016-04-21 Thread Faisal Vali via cfe-commits 
faisalv added inline comments.


Comment at: include/clang/AST/DeclTemplate.h:175
@@ -152,2 +174,3 @@
+  Expr *RequiresClause;
 
 public:

Yuk - this entire guy (FizedSizeTemplateParameterListStorage) seems quite 
fragile (dependent on object layout) - are the gains (in the single use below 
during auto-type deduction) in preformance really worth the introduction of 
this fragility/ugliness? 
Unless there is a clear win from this strategy, I think i'd favor (perhaps in a 
later patch) - either just removing this structure and using TPL for the 
use-case in auto-type below, or using placement new and creating the stack TPL 
on a stack unsigned char array?
Thoughts?



http://reviews.llvm.org/D19322



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Re: [PATCH] D19322: Concepts: Create space for requires-clause in TemplateParameterList; NFC

2016-04-20 Thread Hubert Tong via cfe-commits 
hubert.reinterpretcast updated this revision to Diff 54456.
hubert.reinterpretcast added a comment.

Actually add parens this time


http://reviews.llvm.org/D19322

Files:
  include/clang/AST/DeclTemplate.h
  lib/AST/DeclTemplate.cpp
  lib/Sema/SemaTemplateDeduction.cpp

Index: lib/Sema/SemaTemplateDeduction.cpp
===
--- lib/Sema/SemaTemplateDeduction.cpp
+++ lib/Sema/SemaTemplateDeduction.cpp
@@ -4034,8 +4034,8 @@
  nullptr, false, false);
   QualType TemplArg = QualType(TemplParam->getTypeForDecl(), 0);
   NamedDecl *TemplParamPtr = TemplParam;
-  FixedSizeTemplateParameterListStorage<1> TemplateParamsSt(
-  Loc, Loc, TemplParamPtr, Loc);
+  FixedSizeTemplateParameterListStorage<1, false> TemplateParamsSt(
+  Loc, Loc, TemplParamPtr, Loc, nullptr);
 
   QualType FuncParam = SubstituteAutoTransform(*this, TemplArg).Apply(Type);
   assert(!FuncParam.isNull() &&
Index: lib/AST/DeclTemplate.cpp
===
--- lib/AST/DeclTemplate.cpp
+++ lib/AST/DeclTemplate.cpp
@@ -31,9 +31,11 @@
 TemplateParameterList::TemplateParameterList(SourceLocation TemplateLoc,
  SourceLocation LAngleLoc,
  ArrayRef Params,
- SourceLocation RAngleLoc)
+ SourceLocation RAngleLoc,
+ Expr *RequiresClause)
   : TemplateLoc(TemplateLoc), LAngleLoc(LAngleLoc), RAngleLoc(RAngleLoc),
-NumParams(Params.size()), ContainsUnexpandedParameterPack(false) {
+NumParams(Params.size()), ContainsUnexpandedParameterPack(false),
+HasRequiresClause(static_cast(RequiresClause)) {
   assert(this->NumParams == NumParams && "Too many template parameters");
   for (unsigned Idx = 0; Idx < NumParams; ++Idx) {
 NamedDecl *P = Params[Idx];
@@ -52,15 +54,21 @@
   // template parameter list does too.
 }
   }
+  if (RequiresClause) {
+*getTrailingObjects() = RequiresClause;
+  }
 }
 
-TemplateParameterList *TemplateParameterList::Create(
-const ASTContext &C, SourceLocation TemplateLoc, SourceLocation LAngleLoc,
-ArrayRef Params, SourceLocation RAngleLoc) {
-  void *Mem = C.Allocate(totalSizeToAlloc(Params.size()),
+TemplateParameterList *
+TemplateParameterList::Create(const ASTContext &C, SourceLocation TemplateLoc,
+  SourceLocation LAngleLoc,
+  ArrayRef Params,
+  SourceLocation RAngleLoc, Expr *RequiresClause) {
+  void *Mem = C.Allocate(totalSizeToAlloc(
+ Params.size(), RequiresClause ? 1u : 0u),
  llvm::alignOf());
   return new (Mem) TemplateParameterList(TemplateLoc, LAngleLoc, Params,
- RAngleLoc);
+ RAngleLoc, RequiresClause);
 }
 
 unsigned TemplateParameterList::getMinRequiredArguments() const {
Index: include/clang/AST/DeclTemplate.h
===
--- include/clang/AST/DeclTemplate.h
+++ include/clang/AST/DeclTemplate.h
@@ -46,7 +46,8 @@
 /// \brief Stores a list of template parameters for a TemplateDecl and its
 /// derived classes.
 class TemplateParameterList final
-: private llvm::TrailingObjects {
+: private llvm::TrailingObjects {
 
   /// The location of the 'template' keyword.
   SourceLocation TemplateLoc;
@@ -56,26 +57,36 @@
 
   /// The number of template parameters in this template
   /// parameter list.
-  unsigned NumParams : 31;
+  unsigned NumParams : 30;
 
   /// Whether this template parameter list contains an unexpanded parameter
   /// pack.
   unsigned ContainsUnexpandedParameterPack : 1;
 
+  /// Whether this template parameter list has an associated requires-clause
+  unsigned HasRequiresClause : 1;
+
 protected:
   size_t numTrailingObjects(OverloadToken) const {
 return NumParams;
   }
 
+  size_t numTrailingObjects(OverloadToken) const {
+return HasRequiresClause;
+  }
+
   TemplateParameterList(SourceLocation TemplateLoc, SourceLocation LAngleLoc,
-ArrayRef Params, SourceLocation RAngleLoc);
+ArrayRef Params, SourceLocation RAngleLoc,
+Expr *RequiresClause);
 
 public:
+  // FIXME: remove default argument for RequiresClause
   static TemplateParameterList *Create(const ASTContext &C,
SourceLocation TemplateLoc,
SourceLocation LAngleLoc,
ArrayRef Params,
-   SourceLocation RAngleLoc);
+   SourceLocation RAngleLoc,
+   Expr *RequiresClause =

Re: [PATCH] D19322: Concepts: Create space for requires-clause in TemplateParameterList; NFC

2016-04-20 Thread Hubert Tong via cfe-commits 
hubert.reinterpretcast updated this revision to Diff 54455.
hubert.reinterpretcast added a comment.

Store the RequiresClause expression into the created storage;
add accessor;
add unnecessary parens to silence warning


http://reviews.llvm.org/D19322

Files:
  include/clang/AST/DeclTemplate.h
  lib/AST/DeclTemplate.cpp
  lib/Sema/SemaTemplateDeduction.cpp

Index: lib/Sema/SemaTemplateDeduction.cpp
===
--- lib/Sema/SemaTemplateDeduction.cpp
+++ lib/Sema/SemaTemplateDeduction.cpp
@@ -4034,8 +4034,8 @@
  nullptr, false, false);
   QualType TemplArg = QualType(TemplParam->getTypeForDecl(), 0);
   NamedDecl *TemplParamPtr = TemplParam;
-  FixedSizeTemplateParameterListStorage<1> TemplateParamsSt(
-  Loc, Loc, TemplParamPtr, Loc);
+  FixedSizeTemplateParameterListStorage<1, false> TemplateParamsSt(
+  Loc, Loc, TemplParamPtr, Loc, nullptr);
 
   QualType FuncParam = SubstituteAutoTransform(*this, TemplArg).Apply(Type);
   assert(!FuncParam.isNull() &&
Index: lib/AST/DeclTemplate.cpp
===
--- lib/AST/DeclTemplate.cpp
+++ lib/AST/DeclTemplate.cpp
@@ -31,9 +31,11 @@
 TemplateParameterList::TemplateParameterList(SourceLocation TemplateLoc,
  SourceLocation LAngleLoc,
  ArrayRef Params,
- SourceLocation RAngleLoc)
+ SourceLocation RAngleLoc,
+ Expr *RequiresClause)
   : TemplateLoc(TemplateLoc), LAngleLoc(LAngleLoc), RAngleLoc(RAngleLoc),
-NumParams(Params.size()), ContainsUnexpandedParameterPack(false) {
+NumParams(Params.size()), ContainsUnexpandedParameterPack(false),
+HasRequiresClause(static_cast(RequiresClause)) {
   assert(this->NumParams == NumParams && "Too many template parameters");
   for (unsigned Idx = 0; Idx < NumParams; ++Idx) {
 NamedDecl *P = Params[Idx];
@@ -52,15 +54,21 @@
   // template parameter list does too.
 }
   }
+  if (RequiresClause) {
+*getTrailingObjects() = RequiresClause;
+  }
 }
 
-TemplateParameterList *TemplateParameterList::Create(
-const ASTContext &C, SourceLocation TemplateLoc, SourceLocation LAngleLoc,
-ArrayRef Params, SourceLocation RAngleLoc) {
-  void *Mem = C.Allocate(totalSizeToAlloc(Params.size()),
+TemplateParameterList *
+TemplateParameterList::Create(const ASTContext &C, SourceLocation TemplateLoc,
+  SourceLocation LAngleLoc,
+  ArrayRef Params,
+  SourceLocation RAngleLoc, Expr *RequiresClause) {
+  void *Mem = C.Allocate(totalSizeToAlloc(
+ Params.size(), RequiresClause ? 1u : 0u),
  llvm::alignOf());
   return new (Mem) TemplateParameterList(TemplateLoc, LAngleLoc, Params,
- RAngleLoc);
+ RAngleLoc, RequiresClause);
 }
 
 unsigned TemplateParameterList::getMinRequiredArguments() const {
Index: include/clang/AST/DeclTemplate.h
===
--- include/clang/AST/DeclTemplate.h
+++ include/clang/AST/DeclTemplate.h
@@ -46,7 +46,8 @@
 /// \brief Stores a list of template parameters for a TemplateDecl and its
 /// derived classes.
 class TemplateParameterList final
-: private llvm::TrailingObjects {
+: private llvm::TrailingObjects {
 
   /// The location of the 'template' keyword.
   SourceLocation TemplateLoc;
@@ -56,26 +57,36 @@
 
   /// The number of template parameters in this template
   /// parameter list.
-  unsigned NumParams : 31;
+  unsigned NumParams : 30;
 
   /// Whether this template parameter list contains an unexpanded parameter
   /// pack.
   unsigned ContainsUnexpandedParameterPack : 1;
 
+  /// Whether this template parameter list has an associated requires-clause
+  unsigned HasRequiresClause : 1;
+
 protected:
   size_t numTrailingObjects(OverloadToken) const {
 return NumParams;
   }
 
+  size_t numTrailingObjects(OverloadToken) const {
+return HasRequiresClause;
+  }
+
   TemplateParameterList(SourceLocation TemplateLoc, SourceLocation LAngleLoc,
-ArrayRef Params, SourceLocation RAngleLoc);
+ArrayRef Params, SourceLocation RAngleLoc,
+Expr *RequiresClause);
 
 public:
+  // FIXME: remove default argument for RequiresClause
   static TemplateParameterList *Create(const ASTContext &C,
SourceLocation TemplateLoc,
SourceLocation LAngleLoc,
ArrayRef Params,
-   SourceLocation RAngleLoc);
+   S