Handle temporaries in default arguments.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@73462 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index 34513e7..28fb918 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -1661,8 +1661,8 @@
   /// MaybeCreateCXXExprWithTemporaries - If the list of temporaries is 
   /// non-empty, will create a new CXXExprWithTemporaries expression.
   /// Otherwise, just returs the passed in expression.
-  Expr *MaybeCreateCXXExprWithTemporaries(Expr *SubExpr, 
-                                          bool DestroyTemps = true);
+  Expr *MaybeCreateCXXExprWithTemporaries(Expr *SubExpr,
+                                          bool ShouldDestroyTemporaries);
   
   virtual OwningExprResult ActOnFinishFullExpr(ExprArg Expr);
 
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 8f64e78..70057a3 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -147,8 +147,11 @@
     return;
   }
 
+  DefaultArgPtr = MaybeCreateCXXExprWithTemporaries(DefaultArg.take(),
+                                                    /*DestroyTemps=*/false);
+  
   // Okay: add the default argument to the parameter
-  Param->setDefaultArg(DefaultArg.take());
+  Param->setDefaultArg(DefaultArgPtr);
 }
 
 /// ActOnParamUnparsedDefaultArgument - We've seen a default
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index c01c812..c046941 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -2491,8 +2491,21 @@
         FDecl << cast<CXXRecordDecl>(FDecl->getDeclContext())->getDeclName();
         Diag(UnparsedDefaultArgLocs[FDecl->getParamDecl(i)], 
               diag::note_default_argument_declared_here);
+      } else {
+        Expr *DefaultExpr = FDecl->getParamDecl(i)->getDefaultArg();
+        
+        // If the default expression creates temporaries, we need to
+        // push them to the current stack of expression temporaries so they'll
+        // be properly destroyed.
+        if (CXXExprWithTemporaries *E 
+              = dyn_cast_or_null<CXXExprWithTemporaries>(DefaultExpr)) {
+          assert(!E->shouldDestroyTemporaries() && 
+                 "Can't destroy temporaries in a default argument expr!");
+          for (unsigned I = 0, N = E->getNumTemporaries(); I != N; ++I)
+            ExprTemporaries.push_back(E->getTemporary(I));
+        }
       }
-      
+  
       // We already type-checked the argument, so we know it works.
       Arg = new (Context) CXXDefaultArgExpr(FDecl->getParamDecl(i));
     }
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index ed4ac55..7353efb 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -1589,7 +1589,7 @@
 }
 
 Expr *Sema::MaybeCreateCXXExprWithTemporaries(Expr *SubExpr, 
-                                              bool DestroyTemps) {
+                                              bool ShouldDestroyTemps) {
   assert(SubExpr && "sub expression can't be null!");
   
   if (ExprTemporaries.empty())
@@ -1598,7 +1598,7 @@
   Expr *E = CXXExprWithTemporaries::Create(Context, SubExpr,
                                            &ExprTemporaries[0], 
                                            ExprTemporaries.size(),
-                                           DestroyTemps);
+                                           ShouldDestroyTemps);
   ExprTemporaries.clear();
   
   return E;
@@ -1607,7 +1607,8 @@
 Sema::OwningExprResult Sema::ActOnFinishFullExpr(ExprArg Arg) {
   Expr *FullExpr = Arg.takeAs<Expr>();
   if (FullExpr)
-    FullExpr = MaybeCreateCXXExprWithTemporaries(FullExpr);
+    FullExpr = MaybeCreateCXXExprWithTemporaries(FullExpr, 
+                                                 /*ShouldDestroyTemps=*/true);
 
   return Owned(FullExpr);
 }
diff --git a/lib/Sema/SemaTemplateInstantiateExpr.cpp b/lib/Sema/SemaTemplateInstantiateExpr.cpp
index 3c67f2a..bf19701 100644
--- a/lib/Sema/SemaTemplateInstantiateExpr.cpp
+++ b/lib/Sema/SemaTemplateInstantiateExpr.cpp
@@ -1165,7 +1165,10 @@
   if (SubExpr.isInvalid())
     return SemaRef.ExprError();
 
-  return SemaRef.ActOnFinishFullExpr(move(SubExpr));
+  Expr *Temp = 
+    SemaRef.MaybeCreateCXXExprWithTemporaries(SubExpr.takeAs<Expr>(),
+                                              E->shouldDestroyTemporaries());
+  return SemaRef.Owned(Temp);
 }
 
 Sema::OwningExprResult