Typo.  HAVE_SYNC -> HAVE_FSYNC
diff --git a/pyconfig.h.in b/pyconfig.h.in
index 6c0a744..2ab8b9c 100644
--- a/pyconfig.h.in
+++ b/pyconfig.h.in
@@ -486,7 +486,7 @@
 #undef HAVE_SYMLINK
 
 /* Define if you have the 'fsync' function. */
-#undef HAVE_SYNC
+#undef HAVE_FSYNC
 
 /* Define to 1 if you have the `sysconf' function. */
 #undef HAVE_SYSCONF