PR22367: Don't forget to create a CXXFunctionalCastExpr around

list-initialization that gets converted to some form other than an
InitListExpr. CXXTemporaryObjectExpr is a special case here, because it
represents a fused CXXFunctionalCastExpr + CXXConstructExpr. That, in
itself, is probably a design error...

llvm-svn: 227377

4 files changed, 44 insertions, 10 deletions

diff --git a/clang/lib/AST/StmtPrinter.cpp b/clang/lib/AST/StmtPrinter.cpp
index 927a679244b..8a86f2a5748 100644
--- a/clang/lib/AST/StmtPrinter.cpp
+++ b/clang/lib/AST/StmtPrinter.cpp
@@ -1679,9 +1679,13 @@ void StmtPrinter::VisitCXXDefaultInitExpr(CXXDefaultInitExpr *Node) {
 
 void StmtPrinter::VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr *Node) {
   Node->getType().print(OS, Policy);
-  OS << "(";
+  // If there are no parens, this is list-initialization, and the braces are
+  // part of the syntax of the inner construct.
+  if (Node->getLParenLoc().isValid())
+    OS << "(";
   PrintExpr(Node->getSubExpr());
-  OS << ")";
+  if (Node->getLParenLoc().isValid())
+    OS << ")";
 }
 
 void StmtPrinter::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *Node) {
@@ -1690,7 +1694,10 @@ void StmtPrinter::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *Node) {
 
 void StmtPrinter::VisitCXXTemporaryObjectExpr(CXXTemporaryObjectExpr *Node) {
   Node->getType().print(OS, Policy);
-  OS << "(";
+  if (Node->isListInitialization())
+    OS << "{";
+  else
+    OS << "(";
   for (CXXTemporaryObjectExpr::arg_iterator Arg = Node->arg_begin(),
                                          ArgEnd = Node->arg_end();
        Arg != ArgEnd; ++Arg) {
@@ -1700,7 +1707,10 @@ void StmtPrinter::VisitCXXTemporaryObjectExpr(CXXTemporaryObjectExpr *Node) {
       OS << ", ";
     PrintExpr(*Arg);
   }
-  OS << ")";
+  if (Node->isListInitialization())
+    OS << "}";
+  else
+    OS << ")";
 }
 
 void StmtPrinter::VisitLambdaExpr(LambdaExpr *Node) {
diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index 96486e8d867..716e59458ae 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -985,18 +985,21 @@ Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo,
   Expr *Inner = Result.get();
   if (CXXBindTemporaryExpr *BTE = dyn_cast_or_null<CXXBindTemporaryExpr>(Inner))
     Inner = BTE->getSubExpr();
-  if (isa<InitListExpr>(Inner)) {
-    // If the list-initialization doesn't involve a constructor call, we'll get
-    // the initializer-list (with corrected type) back, but that's not what we
-    // want, since it will be treated as an initializer list in further
-    // processing. Explicitly insert a cast here.
+  if (!isa<CXXTemporaryObjectExpr>(Inner)) {
+    // If we created a CXXTemporaryObjectExpr, that node also represents the
+    // functional cast. Otherwise, create an explicit cast to represent
+    // the syntactic form of a functional-style cast that was used here.
+    //
+    // FIXME: Creating a CXXFunctionalCastExpr around a CXXConstructExpr
+    // would give a more consistent AST representation than using a
+    // CXXTemporaryObjectExpr. It's also weird that the functional cast
+    // is sometimes handled by initialization and sometimes not.
     QualType ResultType = Result.get()->getType();
     Result = CXXFunctionalCastExpr::Create(
         Context, ResultType, Expr::getValueKindForType(TInfo->getType()), TInfo,
         CK_NoOp, Result.get(), /*Path=*/nullptr, LParenLoc, RParenLoc);
   }
 
-  // FIXME: Improve AST representation?
   return Result;
 }
 
diff --git a/clang/test/SemaCXX/ast-print.cpp b/clang/test/SemaCXX/ast-print.cpp
index baece3c2b32..b0bf245e5cb 100644
--- a/clang/test/SemaCXX/ast-print.cpp
+++ b/clang/test/SemaCXX/ast-print.cpp
@@ -213,3 +213,9 @@ namespace {
 // CHECK: struct {{\[\[gnu::visibility\(\"hidden\"\)\]\]}} S;
 struct [[gnu::visibility("hidden")]] S;
 }
+
+// CHECK: struct CXXFunctionalCastExprPrint fce = CXXFunctionalCastExprPrint{ };
+struct CXXFunctionalCastExprPrint {} fce = CXXFunctionalCastExprPrint{};
+
+// CHECK: struct CXXTemporaryObjectExprPrint toe = CXXTemporaryObjectExprPrint{};
+struct CXXTemporaryObjectExprPrint { CXXTemporaryObjectExprPrint(); } toe = CXXTemporaryObjectExprPrint{};
diff --git a/clang/test/SemaCXX/cxx0x-initializer-stdinitializerlist.cpp b/clang/test/SemaCXX/cxx0x-initializer-stdinitializerlist.cpp
index 70f7c642a54..e7b515305d4 100644
--- a/clang/test/SemaCXX/cxx0x-initializer-stdinitializerlist.cpp
+++ b/clang/test/SemaCXX/cxx0x-initializer-stdinitializerlist.cpp
@@ -259,3 +259,18 @@ namespace ListInitInstantiate {
   template<typename T> void g() { int k = f({0}); }
   template void g<int>();
 }
+
+namespace TemporaryInitListSourceRange_PR22367 {
+  struct A {
+    constexpr A() {}
+    A(std::initializer_list<int>); // expected-note {{here}}
+  };
+  constexpr int f(A) { return 0; }
+  constexpr int k = f( // expected-error {{must be initialized by a constant expression}}
+      // The point of this test is to check that the caret points to
+      // 'std::initializer_list', not to '{0}'.
+      std::initializer_list // expected-note {{constructor}}
+      <int>
+      {0}
+      );
+}