diff --git a/src/test/regress/pg_regress.h b/src/test/regress/pg_regress.h
index 5b636ca3009..141521c8910 100644
--- a/src/test/regress/pg_regress.h
+++ b/src/test/regress/pg_regress.h
@@ -18,8 +18,6 @@
 #define INVALID_PID INVALID_HANDLE_VALUE
 #endif
 
-struct StringInfoData;			/* avoid including stringinfo.h here */
-
 /* simple list of strings */
 typedef struct _stringlist
 {