1 files changed, 21 insertions, 0 deletions
diff --git a/src/backend/access/gist/gistutil.c b/src/backend/access/gist/gistutil.c
index 28ab575425e..d488bbb4200 100644
--- a/src/backend/access/gist/gistutil.c
+++ b/src/backend/access/gist/gistutil.c
@@ -677,3 +677,24 @@ gistoptions(PG_FUNCTION_ARGS)
 		PG_RETURN_BYTEA_P(result);
 	PG_RETURN_NULL();
 }
+
+/*
+ * Temporary GiST indexes are not WAL-logged, but we need LSNs to detect
+ * concurrent page splits anyway. GetXLogRecPtrForTemp() provides a fake
+ * sequence of LSNs for that purpose. Each call generates an LSN that is
+ * greater than any previous value returned by this function in the same
+ * session.
+ */
+XLogRecPtr
+GetXLogRecPtrForTemp(void)
+{
+	static XLogRecPtr counter = {0, 1};
+
+	counter.xrecoff++;
+	if (counter.xrecoff == 0)
+	{
+		counter.xlogid++;
+		counter.xrecoff++;
+	}
+	return counter;
+}