Anonymous SF bug report #128053 point out that the #ifdef for
including "tmpfile" in the posix_methods[] array is wrong -- should be
HAVE_TMPFILE, not HAVE_TMPNAM.
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 4709674..b57bc02 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -5357,7 +5357,7 @@
 #ifdef HAVE_STATVFS
 	{"statvfs",	posix_statvfs, METH_VARARGS, posix_statvfs__doc__},
 #endif
-#ifdef HAVE_TMPNAM
+#ifdef HAVE_TMPFILE
 	{"tmpfile",	posix_tmpfile, METH_VARARGS, posix_tmpfile__doc__},
 #endif
 #ifdef HAVE_TEMPNAM