Based on this report, I am adding a FUNC_MAX_ARGS define to

bmomjian · bmomjian · commit 42f2e5bd1141 · 2002-04-23T23:46:37.000Z
src/include/pg_config.h.win32.  Certainly if we have INDEX_MAX_KEYS in
there, we should have FUNC_MAX_ARGS too.

Report from Chris Ryan
diff --git a/src/include/pg_config.h.win32 b/src/include/pg_config.h.win32
@@ -19,6 +19,7 @@
 #define BLCKSZ	8192
 
 #define INDEX_MAX_KEYS		16
+#define FUNC_MAX_ARGS		INDEX_MAX_KEYS
 
 #define HAVE_ATEXIT
 #define HAVE_MEMMOVE
