Index: lib/Sema/SemaChecking.cpp
===================================================================
--- lib/Sema/SemaChecking.cpp
+++ lib/Sema/SemaChecking.cpp
@@ -3392,6 +3392,58 @@
   }
 }
 
+static std::pair<QualType, StringRef>
+shouldNotPrintDirectly(const ASTContext &Context,
+                       QualType IntendedTy,
+                       const Expr *E) {
+  // Use a 'while' to peel off layers of typedefs.
+  QualType TyTy = IntendedTy;
+  while (const TypedefType *UserTy = TyTy->getAs<TypedefType>()) {
+    StringRef Name = UserTy->getDecl()->getName();
+    QualType CastTy = llvm::StringSwitch<QualType>(Name)
+      .Case("NSInteger", Context.LongTy)
+      .Case("NSUInteger", Context.UnsignedLongTy)
+      .Case("SInt32", Context.IntTy)
+      .Case("UInt32", Context.UnsignedIntTy)
+      .Default(QualType());
+
+    if (!CastTy.isNull())
+      return { CastTy, Name };
+
+    TyTy = UserTy->desugar();
+  }
+
+  // Strip parens if necessary.
+  if (const ParenExpr *PE = dyn_cast<ParenExpr>(E))
+    return shouldNotPrintDirectly(Context,
+                                  PE->getSubExpr()->getType(),
+                                  PE->getSubExpr());
+
+  // If this is a conditional expression, then its result type is constructed
+  // via usual airthmetic conversions and thus there might be no necessary sugar
+  // there.  Recurse to operands to check for NSInteger & Co. usage condition.
+  if (const ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
+    QualType TrueTy, FalseTy;
+    StringRef TrueName, FalseName;
+
+    std::tie(TrueTy, TrueName) = shouldNotPrintDirectly(Context,
+                                                        CO->getTrueExpr()->getType(),
+                                                        CO->getTrueExpr());
+    std::tie(FalseTy, FalseName) = shouldNotPrintDirectly(Context,
+                                                          CO->getFalseExpr()->getType(),
+                                                          CO->getFalseExpr());
+
+    if (TrueTy == FalseTy)
+      return { TrueTy, TrueName };
+    else if (TrueTy.isNull())
+      return { FalseTy, FalseName };
+    else if (FalseTy.isNull())
+      return { TrueTy, TrueName };
+  }
+
+  return { QualType(), StringRef() };
+}
+
 bool
 CheckPrintfHandler::checkFormatExpr(const analyze_printf::PrintfSpecifier &FS,
                                     const char *StartSpecifier,
@@ -3483,25 +3535,13 @@
 
   // Special-case some of Darwin's platform-independence types by suggesting
   // casts to primitive types that are known to be large enough.
-  bool ShouldNotPrintDirectly = false;
+  bool ShouldNotPrintDirectly = false; StringRef CastTyName;
   if (S.Context.getTargetInfo().getTriple().isOSDarwin()) {
-    // Use a 'while' to peel off layers of typedefs.
-    QualType TyTy = IntendedTy;
-    while (const TypedefType *UserTy = TyTy->getAs<TypedefType>()) {
-      StringRef Name = UserTy->getDecl()->getName();
-      QualType CastTy = llvm::StringSwitch<QualType>(Name)
-        .Case("NSInteger", S.Context.LongTy)
-        .Case("NSUInteger", S.Context.UnsignedLongTy)
-        .Case("SInt32", S.Context.IntTy)
-        .Case("UInt32", S.Context.UnsignedIntTy)
-        .Default(QualType());
-
-      if (!CastTy.isNull()) {
-        ShouldNotPrintDirectly = true;
-        IntendedTy = CastTy;
-        break;
-      }
-      TyTy = UserTy->desugar();
+    QualType CastTy;
+    std::tie(CastTy, CastTyName) = shouldNotPrintDirectly(S.Context, IntendedTy, E);
+    if (!CastTy.isNull()) {
+      IntendedTy = CastTy;
+      ShouldNotPrintDirectly = true;
     }
   }
 
@@ -3518,7 +3558,7 @@
 
     CharSourceRange SpecRange = getSpecifierRange(StartSpecifier, SpecifierLen);
 
-    if (IntendedTy == ExprTy) {
+    if (IntendedTy == ExprTy && !ShouldNotPrintDirectly) {
       // In this case, the specifier is wrong and should be changed to match
       // the argument.
       EmitFormatDiagnostic(
@@ -3572,8 +3612,11 @@
         // The expression has a type that should not be printed directly.
         // We extract the name from the typedef because we don't want to show
         // the underlying type in the diagnostic.
-        StringRef Name = cast<TypedefType>(ExprTy)->getDecl()->getName();
-
+        StringRef Name;
+        if (const TypedefType *TypedefTy = dyn_cast<TypedefType>(ExprTy))
+          Name = TypedefTy->getDecl()->getName();
+        else
+          Name = CastTyName;
         EmitFormatDiagnostic(S.PDiag(diag::warn_format_argument_needs_cast)
                                << Name << IntendedTy << IsEnum
                                << E->getSourceRange(),
Index: lib/Sema/SemaExpr.cpp
===================================================================
--- lib/Sema/SemaExpr.cpp
+++ lib/Sema/SemaExpr.cpp
@@ -5709,7 +5709,7 @@
       RHS.get()->getType()->isVectorType())
     return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false);
 
-  UsualArithmeticConversions(LHS, RHS);
+  QualType ResTy = UsualArithmeticConversions(LHS, RHS);
   if (LHS.isInvalid() || RHS.isInvalid())
     return QualType();
 
@@ -5726,8 +5726,12 @@
   
   // If both operands have arithmetic type, do the usual arithmetic conversions
   // to find a common type: C99 6.5.15p3,5.
-  if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType())
-    return LHS.get()->getType();
+  if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) {
+    LHS = ImpCastExprToType(LHS.get(), ResTy, PrepareScalarCast(LHS, ResTy));
+    RHS = ImpCastExprToType(RHS.get(), ResTy, PrepareScalarCast(RHS, ResTy));
+
+    return ResTy;
+  }
 
   // If both operands are the same structure or union type, the result is that
   // type.
Index: lib/Sema/SemaExprCXX.cpp
===================================================================
--- lib/Sema/SemaExprCXX.cpp
+++ lib/Sema/SemaExprCXX.cpp
@@ -4561,10 +4561,14 @@
   //      the usual arithmetic conversions are performed to bring them to a
   //      common type, and the result is of that type.
   if (LTy->isArithmeticType() && RTy->isArithmeticType()) {
-    UsualArithmeticConversions(LHS, RHS);
+    QualType ResTy = UsualArithmeticConversions(LHS, RHS);
     if (LHS.isInvalid() || RHS.isInvalid())
       return QualType();
-    return LHS.get()->getType();
+
+    LHS = ImpCastExprToType(LHS.get(), ResTy, PrepareScalarCast(LHS, ResTy));
+    RHS = ImpCastExprToType(RHS.get(), ResTy, PrepareScalarCast(RHS, ResTy));
+
+    return ResTy;
   }
 
   //   -- The second and third operands have pointer type, or one has pointer
Index: test/CodeGen/complex.c
===================================================================
--- test/CodeGen/complex.c
+++ test/CodeGen/complex.c
@@ -98,3 +98,12 @@
 
 const _Complex double test9const = 0;
 _Complex double test9func() { return test9const; }
+
+// D6217
+void t9() {
+  // Check for proper type promotion of conditional expression
+  char c[(int)(sizeof(typeof((0 ? 2.0f : (_Complex double) 2.0f))) - sizeof(_Complex double))];
+  // Check for proper codegen
+  (0 ? 2.0f : (_Complex double) 2.0f);
+}
+