diff --git a/ConflictSet.cpp b/ConflictSet.cpp
index 3f57c71..7be48e0 100644
--- a/ConflictSet.cpp
+++ b/ConflictSet.cpp
@@ -1613,7 +1613,8 @@ void addWriteRange(Node *&root, int64_t oldestVersion,
 
   auto *beginNode = insert<true>(useAsRoot, begin, writeVersion, impl);
 
-  const bool insertedBegin = !std::exchange(beginNode->entryPresent, true);
+  const bool insertedBegin = !beginNode->entryPresent;
+  beginNode->entryPresent = true;
 
   if (insertedBegin) {
     auto *p = nextLogical(beginNode);
@@ -1630,7 +1631,8 @@ void addWriteRange(Node *&root, int64_t oldestVersion,
 
   auto *endNode = insert<false>(useAsRoot, end, writeVersion, impl);
 
-  const bool insertedEnd = !std::exchange(endNode->entryPresent, true);
+  const bool insertedEnd = !endNode->entryPresent;
+  endNode->entryPresent = true;
 
   if (insertedEnd) {
     auto *p = nextLogical(endNode);