commit c83d9bedc0cc430dc620e7a807daeb985d390325
author Saar Raz <saar@raz.email> Thu Jan 30 20:42:28 2020 +0200
committer Saar Raz <saar@raz.email> Thu Jan 30 20:45:44 2020 +0200
tree 47e6e43618ea308d8d5a1e87a31d27d2382e6a41
parent 34e6552dcbb4f6647746588bb35591a97a7992a3

[Concept] Fix incorrect check for containsUnexpandedParameterPack in CSE

We previously checked for containsUnexpandedParameterPack in CSEs by observing the property
in the converted arguments of the CSE. This may not work if the argument is an expanded
type-alias that contains a pack-expansion (see added test).

Check the as-written arguments when determining containsUnexpandedParameterPack and isInstantiationDependent.

clang/lib/AST/ASTContext.cpp

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 7296949..c80d394 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -731,12 +731,8 @@
       NewConverted.push_back(Arg);
   }
   Expr *NewIDC = ConceptSpecializationExpr::Create(
-      C, NestedNameSpecifierLoc(), /*TemplateKWLoc=*/SourceLocation(),
-      CSE->getConceptNameInfo(), /*FoundDecl=*/CSE->getNamedConcept(),
-      CSE->getNamedConcept(),
-      // Actually canonicalizing a TemplateArgumentLoc is difficult so we
-      // simply omit the ArgsAsWritten
-      /*ArgsAsWritten=*/nullptr, NewConverted, nullptr);
+      C, CSE->getNamedConcept(), NewConverted, nullptr,
+      CSE->isInstantiationDependent(), CSE->containsUnexpandedParameterPack());
 
   if (auto *OrigFold = dyn_cast<CXXFoldExpr>(IDC))
     NewIDC = new (C) CXXFoldExpr(OrigFold->getType(), SourceLocation(), NewIDC,

clang/lib/AST/ExprConcepts.cpp

diff --git a/clang/lib/AST/ExprConcepts.cpp b/clang/lib/AST/ExprConcepts.cpp
index 76d57ed..b5a3686 100644
--- a/clang/lib/AST/ExprConcepts.cpp
+++ b/clang/lib/AST/ExprConcepts.cpp
@@ -46,24 +46,12 @@
                    ASTConstraintSatisfaction::Create(C, *Satisfaction) :
                    nullptr) {
   setTemplateArguments(ConvertedArgs);
-}
-
-ConceptSpecializationExpr::ConceptSpecializationExpr(EmptyShell Empty,
-    unsigned NumTemplateArgs)
-    : Expr(ConceptSpecializationExprClass, Empty), ConceptReference(),
-      NumTemplateArgs(NumTemplateArgs) { }
-
-void ConceptSpecializationExpr::setTemplateArguments(
-    ArrayRef<TemplateArgument> Converted) {
-  assert(Converted.size() == NumTemplateArgs);
-  std::uninitialized_copy(Converted.begin(), Converted.end(),
-                          getTrailingObjects<TemplateArgument>());
   bool IsInstantiationDependent = false;
   bool ContainsUnexpandedParameterPack = false;
-  for (const TemplateArgument& Arg : Converted) {
-    if (Arg.isInstantiationDependent())
+  for (const TemplateArgumentLoc& ArgLoc : ArgsAsWritten->arguments()) {
+    if (ArgLoc.getArgument().isInstantiationDependent())
       IsInstantiationDependent = true;
-    if (Arg.containsUnexpandedParameterPack())
+    if (ArgLoc.getArgument().containsUnexpandedParameterPack())
       ContainsUnexpandedParameterPack = true;
     if (ContainsUnexpandedParameterPack && IsInstantiationDependent)
       break;
@@ -80,6 +68,18 @@
          "should not be value-dependent");
 }
 
+ConceptSpecializationExpr::ConceptSpecializationExpr(EmptyShell Empty,
+    unsigned NumTemplateArgs)
+    : Expr(ConceptSpecializationExprClass, Empty), ConceptReference(),
+      NumTemplateArgs(NumTemplateArgs) { }
+
+void ConceptSpecializationExpr::setTemplateArguments(
+    ArrayRef<TemplateArgument> Converted) {
+  assert(Converted.size() == NumTemplateArgs);
+  std::uninitialized_copy(Converted.begin(), Converted.end(),
+                          getTrailingObjects<TemplateArgument>());
+}
+
 ConceptSpecializationExpr *
 ConceptSpecializationExpr::Create(const ASTContext &C,
                                   NestedNameSpecifierLoc NNS,
@@ -98,6 +98,39 @@
                                                 ConvertedArgs, Satisfaction);
 }
 
+ConceptSpecializationExpr::ConceptSpecializationExpr(
+    const ASTContext &C, ConceptDecl *NamedConcept,
+    ArrayRef<TemplateArgument> ConvertedArgs,
+    const ConstraintSatisfaction *Satisfaction, bool Dependent,
+    bool ContainsUnexpandedParameterPack)
+    : Expr(ConceptSpecializationExprClass, C.BoolTy, VK_RValue, OK_Ordinary,
+           /*TypeDependent=*/false,
+           /*ValueDependent=*/!Satisfaction, Dependent,
+           ContainsUnexpandedParameterPack),
+      ConceptReference(NestedNameSpecifierLoc(), SourceLocation(),
+                       DeclarationNameInfo(), NamedConcept,
+                       NamedConcept, nullptr),
+      NumTemplateArgs(ConvertedArgs.size()),
+      Satisfaction(Satisfaction ?
+                   ASTConstraintSatisfaction::Create(C, *Satisfaction) :
+                   nullptr) {
+  setTemplateArguments(ConvertedArgs);
+}
+
+ConceptSpecializationExpr *
+ConceptSpecializationExpr::Create(const ASTContext &C,
+                                  ConceptDecl *NamedConcept,
+                                  ArrayRef<TemplateArgument> ConvertedArgs,
+                                  const ConstraintSatisfaction *Satisfaction,
+                                  bool Dependent,
+                                  bool ContainsUnexpandedParameterPack) {
+  void *Buffer = C.Allocate(totalSizeToAlloc<TemplateArgument>(
+                                ConvertedArgs.size()));
+  return new (Buffer) ConceptSpecializationExpr(
+      C, NamedConcept, ConvertedArgs, Satisfaction, Dependent,
+      ContainsUnexpandedParameterPack);
+}
+
 ConceptSpecializationExpr *
 ConceptSpecializationExpr::Create(ASTContext &C, EmptyShell Empty,
                                   unsigned NumTemplateArgs) {