From 7842c3fceadaa1fcef7c91c59d822a572a17c8e2 Mon Sep 17 00:00:00 2001
From: Davide Italiano <davide@freebsd.org>
Date: Sat, 18 Jul 2015 01:15:19 +0000
Subject: [Sema] Emit correct warning when copy-elision is not possible.

If we're returning a function parameter, copy elision isn't possible,
so we now warn for redundant move.

PR:		23819
Differential Revision:	 http://reviews.llvm.org/D11305

llvm-svn: 242600
---
 clang/lib/Sema/SemaInit.cpp | 5 +++++
 1 file changed, 5 insertions(+)

(limited to 'clang/lib/Sema')

diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp
index f0f7cb93d33..25d091f1d8c 100644
--- a/clang/lib/Sema/SemaInit.cpp
+++ b/clang/lib/Sema/SemaInit.cpp
@@ -5988,6 +5988,11 @@ static void CheckMoveOnConstruction(Sema &S, const Expr *InitExpr,
     if (!VD->getType()->isRecordType())
       return;
 
+    // If we're returning a function parameter, copy elision
+    // is not possible.
+    if (isa<ParmVarDecl>(VD))
+      DiagID = diag::warn_redundant_move_on_return;
+
     if (DiagID == 0) {
       DiagID = S.Context.hasSameUnqualifiedType(DestType, VD->getType())
                    ? diag::warn_pessimizing_move_on_return
-- 
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