diff --git i/src/test/regress/pg_regress.c w/src/test/regress/pg_regress.c
index 2f6b37b..1384223 100644
--- i/src/test/regress/pg_regress.c
+++ w/src/test/regress/pg_regress.c
@@ -691,6 +691,8 @@ initialize_environment(void)
 {
 	char	   *tmp;
 
+	putenv("PGAPPNAME=pg_regress");
+
 	if (nolocale)
 	{
 		/*