From 15453b3284af6796c39edcc70a748de8a8ace388 Mon Sep 17 00:00:00 2001
From: Jonathan Lifflander <jliffla@sandia.gov>
Date: Wed, 14 Sep 2022 11:22:04 -0700
Subject: [PATCH] #1899: td: take message by const&

---
 src/vt/context/runnable_context/td.h      | 2 +-
 src/vt/context/runnable_context/td.impl.h | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/vt/context/runnable_context/td.h b/src/vt/context/runnable_context/td.h
index bd3c4ab494..8a0cf0f913 100644
--- a/src/vt/context/runnable_context/td.h
+++ b/src/vt/context/runnable_context/td.h
@@ -78,7 +78,7 @@ struct TD {
    * \param[in] msg the message to extract the epoch from
    */
   template <typename MsgPtrT>
-  explicit TD(MsgPtrT msg);
+  explicit TD(MsgPtrT const& msg);
 
   /**
    * \brief During begin \c TD will capture the epoch stack size and push \c ep_
diff --git a/src/vt/context/runnable_context/td.impl.h b/src/vt/context/runnable_context/td.impl.h
index e456ffd713..0992a18b54 100644
--- a/src/vt/context/runnable_context/td.impl.h
+++ b/src/vt/context/runnable_context/td.impl.h
@@ -60,7 +60,7 @@ namespace {
  * \return the associated epoch
  */
 template <typename MsgPtrT>
-static EpochType extractEpochMsg(MsgPtrT msg) {
+static EpochType extractEpochMsg(MsgPtrT const& msg) {
   auto const is_term = envelopeIsTerm(msg->env);
   if (not is_term) {
     auto ep_ = envelopeIsEpochType(msg->env) ?
@@ -77,7 +77,7 @@ static EpochType extractEpochMsg(MsgPtrT msg) {
 } /* end anon namespace */
 
 template <typename MsgPtrT>
-/*explicit*/ TD::TD(MsgPtrT msg)
+/*explicit*/ TD::TD(MsgPtrT const& msg)
   : TD(extractEpochMsg(msg))
 { }