diff --git a/src/include/pg_config.h.win32 b/src/include/pg_config.h.win32
index 97b9aa219c..ffa386c992 100644
--- a/src/include/pg_config.h.win32
+++ b/src/include/pg_config.h.win32
@@ -23,6 +23,12 @@
 #define HAVE_RANDOM
 #endif
 
+/* use _snprintf and _vsnprintf */
+#define HAVE_DECL_SNPRINTF 1
+#define snprintf        _snprintf
+#define HAVE_DECL_VSNPRINTF 1
+#define vsnprintf       _vsnprintf
+
 /* defines for dynamic linking on Win32 platform */
 #ifdef __CYGWIN__