5 files changed, 42 insertions, 6 deletions

diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index 1ef14a2284..7708731947 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -4113,9 +4113,11 @@ public:
   QualType CheckCommaOperands( // C99 6.5.17
     Expr *lex, Expr *&rex, SourceLocation OpLoc);
   QualType CheckConditionalOperands( // C99 6.5.15
-    Expr *&cond, Expr *&lhs, Expr *&rhs, SourceLocation questionLoc);
+    Expr *&cond, Expr *&lhs, Expr *&rhs, Expr *&save,
+    SourceLocation questionLoc);
   QualType CXXCheckConditionalOperands( // C++ 5.16
-    Expr *&cond, Expr *&lhs, Expr *&rhs, SourceLocation questionLoc);
+    Expr *&cond, Expr *&lhs, Expr *&rhs, Expr *&save, 
+    SourceLocation questionLoc);
   QualType FindCompositePointerType(SourceLocation Loc, Expr *&E1, Expr *&E2,
                                     bool *NonStandardCompositeType = 0);
 
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index c65db7e835..4bd596b672 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -4203,13 +4203,18 @@ ExprResult Sema::ActOnParenOrParenListExpr(SourceLocation L,
 /// In that case, lhs = cond.
 /// C99 6.5.15
 QualType Sema::CheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS,
+                                        Expr *&SAVE,
                                         SourceLocation QuestionLoc) {
   // C++ is sufficiently different to merit its own checker.
   if (getLangOptions().CPlusPlus)
-    return CXXCheckConditionalOperands(Cond, LHS, RHS, QuestionLoc);
+    return CXXCheckConditionalOperands(Cond, LHS, RHS, SAVE, QuestionLoc);
 
   UsualUnaryConversions(Cond);
-  UsualUnaryConversions(LHS);
+  if (SAVE) {
+    SAVE = LHS = Cond;
+  }
+  else
+    UsualUnaryConversions(LHS);
   UsualUnaryConversions(RHS);
   QualType CondTy = Cond->getType();
   QualType LHSTy = LHS->getType();
@@ -4534,8 +4539,8 @@ ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc,
     LHSExpr = SAVEExpr = CondExpr;
   }
 
-  QualType result = CheckConditionalOperands(CondExpr, LHSExpr,
-                                             RHSExpr, QuestionLoc);
+  QualType result = CheckConditionalOperands(CondExpr, LHSExpr, RHSExpr, 
+                                             SAVEExpr, QuestionLoc);
   if (result.isNull())
     return ExprError();
 
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index 30ac6189f7..80dbe459ce 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -2490,6 +2490,7 @@ static bool ConvertForConditional(Sema &Self, Expr *&E, QualType T) {
 /// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y
 /// extension. In this case, LHS == Cond. (But they're not aliases.)
 QualType Sema::CXXCheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS,
+                                           Expr *&SAVE,
                                            SourceLocation QuestionLoc) {
   // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++
   // interface pointers.
@@ -2497,6 +2498,12 @@ QualType Sema::CXXCheckConditionalOperands(Expr *&Cond, Expr *&LHS, Expr *&RHS,
   // C++0x 5.16p1
   //   The first expression is contextually converted to bool.
   if (!Cond->isTypeDependent()) {
+    if (SAVE && Cond->getType()->isArrayType()) {
+      QualType CondTy = Cond->getType();
+      CondTy = Context.getArrayDecayedType(CondTy);
+      ImpCastExprToType(Cond, CondTy, CK_ArrayToPointerDecay);
+      SAVE = LHS = Cond;
+    }
     if (CheckCXXBooleanCondition(Cond))
       return QualType();
   }
diff --git a/test/CodeGen/conditional-gnu-ext.c b/test/CodeGen/conditional-gnu-ext.c
index f4ac81bf59..5e5801af93 100644
--- a/test/CodeGen/conditional-gnu-ext.c
+++ b/test/CodeGen/conditional-gnu-ext.c
@@ -10,3 +10,12 @@ float test(float x, int Y) {
   return Y != 0 ? : x;
 }
 
+// rdar://8446940
+extern void abort();
+void  test1 () {
+  char x[1];
+  char *y = x ? : 0;
+
+  if (x != y)
+    abort();
+}
diff --git a/test/CodeGenCXX/gnu-conditional-scalar-ext.cpp b/test/CodeGenCXX/gnu-conditional-scalar-ext.cpp
index 8c529c30e1..dfd9d41489 100644
--- a/test/CodeGenCXX/gnu-conditional-scalar-ext.cpp
+++ b/test/CodeGenCXX/gnu-conditional-scalar-ext.cpp
@@ -9,3 +9,16 @@ int main(int argc, char **argv) {
     printf("%p\n", (void *)0xdeadbeef ? : (void *)0xaaaaaa);
     return 0;
 }
+
+// rdar://8446940
+namespace radar8446940 {
+extern "C" void abort();
+
+int main () {
+  char x[1];
+  char *y = x ? : 0;
+
+  if (x != y)
+    abort();
+}
+}