diff --git a/src/port/snprintf.c b/src/port/snprintf.c
index b7eb2d7f27..61b452844c 100644
--- a/src/port/snprintf.c
+++ b/src/port/snprintf.c
@@ -109,6 +109,16 @@
 #undef	vprintf
 #undef	printf
 
+/*
+ * We use the platform's native snprintf() for some machine-dependent cases.
+ * While that's required by C99, Microsoft Visual Studio lacks it before
+ * VS2015.  Fortunately, we don't really need the length check in practice,
+ * so just fall back to native sprintf() on that platform.
+ */
+#if defined(_MSC_VER) && _MSC_VER < 1900	/* pre-VS2015 */
+#define snprintf(str,size,...) sprintf(str,__VA_ARGS__)
+#endif
+
 /*
  * Info about where the formatted output is going.
  *