[Temporary] Add an ExprWithCleanups for each C++ MaterializeTemporaryExpr.

These ExprWithCleanups are added for holding a RunCleanupsScope not
for destructor calls; rather, they are for lifetime marks. This requires
ExprWithCleanups to keep a bit to indicate whether it have cleanups with
side effects (e.g. dtor calls).

Differential Revision: http://reviews.llvm.org/D20498

llvm-svn: 272296

1 files changed, 8 insertions, 0 deletions

diff --git a/clang/lib/Sema/SemaStmt.cpp b/clang/lib/Sema/SemaStmt.cpp
index d2d4098d177..7156cd2a9ad 100644
--- a/clang/lib/Sema/SemaStmt.cpp
+++ b/clang/lib/Sema/SemaStmt.cpp
@@ -1518,6 +1518,10 @@ namespace {
   // variables Increment and DRE.
   bool ProcessIterationStmt(Sema &S, Stmt* Statement, bool &Increment,
                             DeclRefExpr *&DRE) {
+    if (auto Cleanups = dyn_cast<ExprWithCleanups>(Statement))
+      if (!Cleanups->cleanupsHaveSideEffects())
+        Statement = Cleanups->getSubExpr();
+
     if (UnaryOperator *UO = dyn_cast<UnaryOperator>(Statement)) {
       switch (UO->getOpcode()) {
         default: return false;
@@ -2472,6 +2476,10 @@ static void DiagnoseForRangeReferenceVariableCopies(Sema &SemaRef,
 
   QualType VariableType = VD->getType();
 
+  if (auto Cleanups = dyn_cast<ExprWithCleanups>(InitExpr))
+    if (!Cleanups->cleanupsHaveSideEffects())
+      InitExpr = Cleanups->getSubExpr();
+
   const MaterializeTemporaryExpr *MTE =
       dyn_cast<MaterializeTemporaryExpr>(InitExpr);