Clean up the AST for while loops and fix several problems with

cleanups for while loops: 

1) Make sure that we destroy the condition variable of a while statement each time through the loop for, e.g.,

   while (shared_ptr<WorkInt> p = getWorkItem()) {
         // ...
         }

2) Make sure that we always enter a new cleanup scope for the body of the while loop, even when there is no compound expression, e.g.,

   while (blah)
     RAIIObject raii(blah+1);



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@89800 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 23 insertions, 2 deletions

diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
index 6ff3d638fe..61d48cb63e 100644
--- a/lib/Sema/SemaStmt.cpp
+++ b/lib/Sema/SemaStmt.cpp
@@ -720,6 +720,15 @@ Sema::ActOnWhileStmt(SourceLocation WhileLoc, FullExprArg Cond, StmtArg Body) {
   Expr *condExpr = CondArg.takeAs<Expr>();
   assert(condExpr && "ActOnWhileStmt(): missing expression");
 
+  VarDecl *ConditionVar = 0;
+  if (CXXConditionDeclExpr *Cond = dyn_cast<CXXConditionDeclExpr>(condExpr)) {
+    ConditionVar = Cond->getVarDecl();
+    condExpr = DeclRefExpr::Create(Context, 0, SourceRange(), ConditionVar,
+                                   ConditionVar->getLocation(), 
+                                 ConditionVar->getType().getNonReferenceType());
+    // FIXME: Leaks the old condExpr
+  }
+
   if (CheckBooleanCondition(condExpr, WhileLoc)) {
     CondArg = condExpr;
     return StmtError();
@@ -729,7 +738,8 @@ Sema::ActOnWhileStmt(SourceLocation WhileLoc, FullExprArg Cond, StmtArg Body) {
   DiagnoseUnusedExprResult(bodyStmt);
 
   CondArg.release();
-  return Owned(new (Context) WhileStmt(condExpr, bodyStmt, WhileLoc));
+  return Owned(new (Context) WhileStmt(ConditionVar, condExpr, bodyStmt, 
+                                       WhileLoc));
 }
 
 Action::OwningStmtResult
diff --git a/lib/Sema/TreeTransform.h b/lib/Sema/TreeTransform.h
index e1d0bba4a4..202e16e31e 100644
--- a/lib/Sema/TreeTransform.h
+++ b/lib/Sema/TreeTransform.h
@@ -3139,7 +3139,18 @@ template<typename Derived>
 Sema::OwningStmtResult
 TreeTransform<Derived>::TransformWhileStmt(WhileStmt *S) {
   // Transform the condition
-  OwningExprResult Cond = getDerived().TransformExpr(S->getCond());
+  OwningExprResult Cond(SemaRef);
+  VarDecl *ConditionVar = 0;
+  if (S->getConditionVariable()) {
+    ConditionVar 
+      = cast_or_null<VarDecl>(
+                   getDerived().TransformDefinition(S->getConditionVariable()));
+    if (!ConditionVar)
+      return SemaRef.StmtError();
+    
+    Cond = getSema().CheckConditionVariable(ConditionVar);
+  } else
+    Cond = getDerived().TransformExpr(S->getCond());
   if (Cond.isInvalid())
     return SemaRef.StmtError();