From: Douglas Gregor <dgregor@apple.com>
Date: Wed, 3 Feb 2010 03:01:57 +0000 (+0000)
Subject: Provide a real fix for PR6199, reverting the old workaround. Here, we
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=321725d95d331d1612ac386d7d4235eca94b0021;p=clang

Provide a real fix for PR6199, reverting the old workaround. Here, we
realize that CXXConstructExpr is always implicit, so we should just
return its argument (if there is only one) rather than directly
invoking the constructor.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@95192 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGExprCXX.cpp b/lib/CodeGen/CGExprCXX.cpp
index 8dd747240a..4253d18c39 100644
--- a/lib/CodeGen/CGExprCXX.cpp
+++ b/lib/CodeGen/CGExprCXX.cpp
@@ -309,9 +309,7 @@ CodeGenFunction::EmitCXXConstructExpr(llvm::Value *Dest,
   if (getContext().getLangOptions().ElideConstructors && E->isElidable()) {
     const Expr *Arg = E->getArg(0);
     
-    // FIXME: This 'while' statement should really be an 'if' statement, it's 
-    // added as a workaround for PR6199.
-    while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Arg)) {
+    if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Arg)) {
       assert((ICE->getCastKind() == CastExpr::CK_NoOp ||
               ICE->getCastKind() == CastExpr::CK_ConstructorConversion ||
               ICE->getCastKind() == CastExpr::CK_UserDefinedConversion) &&
diff --git a/lib/Sema/TreeTransform.h b/lib/Sema/TreeTransform.h
index 1938e3dfb5..b1b85e5928 100644
--- a/lib/Sema/TreeTransform.h
+++ b/lib/Sema/TreeTransform.h
@@ -4808,6 +4808,12 @@ TreeTransform<Derived>::TransformDependentScopeDeclRefExpr(
 template<typename Derived>
 Sema::OwningExprResult
 TreeTransform<Derived>::TransformCXXConstructExpr(CXXConstructExpr *E) {
+  // CXXConstructExprs are always implicit, so when we have a
+  // 1-argument construction we just transform that argument.
+  if (E->getNumArgs() == 1 ||
+      (E->getNumArgs() > 1 && getDerived().DropCallArgument(E->getArg(1))))
+    return getDerived().TransformExpr(E->getArg(0));
+
   TemporaryBase Rebase(*this, /*FIXME*/E->getLocStart(), DeclarationName());
 
   QualType T = getDerived().TransformType(E->getType());