Switch the initialization required by return statements over to the

new InitializationSequence. This fixes some bugs (e.g., PR5808),
changed some diagnostics, and caused more churn than expected. What's
new:

  - InitializationSequence now has a "C conversion sequence" category
    and step kind, which falls back to
  - Changed the diagnostics for returns to always have the result type
    of the function first and the type of the expression second.
    CheckSingleAssignmentConstraints to peform checking in C. 
  - Improved ASTs for initialization of return values. The ASTs now
    capture all of the temporaries we need to create, but
    intentionally do not bind the tempoary that is actually returned,
    so that it won't get destroyed twice.
  - Make sure to perform an (elidable!) copy of the class object that
    is returned from a class.
  - Fix copy elision in CodeGen to properly see through the
    subexpressions that occur with elidable copies.
  - Give "new" its own entity kind; as with return values and thrown
    objects, we don't bind the expression so we don't call a
    destructor for it.

Note that, with this patch, I've broken returning move-only types in
C++0x. We'll fix it later, when we tackle NRVO.

llvm-svn: 91669

1 files changed, 3 insertions, 0 deletions

diff --git a/clang/lib/Sema/Sema.h b/clang/lib/Sema/Sema.h
index 3d03dfd8cee..9d40a13786b 100644
--- a/clang/lib/Sema/Sema.h
+++ b/clang/lib/Sema/Sema.h
@@ -935,6 +935,9 @@ public:
   bool PerformCopyInitialization(Expr *&From, QualType ToType,
                                  AssignmentAction Action, bool Elidable = false);
 
+  OwningExprResult PerformCopyInitialization(const InitializedEntity &Entity,
+                                             SourceLocation EqualLoc,
+                                             OwningExprResult Init);
   ImplicitConversionSequence
   TryObjectArgumentInitialization(QualType FromType, CXXMethodDecl *Method,
                                   CXXRecordDecl *ActingContext);