libstdc++: Add comment to #include in <variant>

It's not obvious why <variant> needs <bits/parse_numbers.h> so add a
comment to it.

libstdc++-v3/ChangeLog:

	* include/std/variant: Add comment to #include.

diff --git a/libstdc++-v3/include/std/variant b/libstdc++-v3/include/std/variant
index f79d95db7a832242c03d869c7e1e73b19c135fa3..748e9bae1cb0cb5f1517039764cfcb6eb2b185b6 100644 (file)
--- a/libstdc++-v3/include/std/variant
+++ b/libstdc++-v3/include/std/variant
@@ -42,7 +42,7 @@
 #include <bits/exception_defines.h>
 #include <bits/functional_hash.h>
 #include <bits/invoke.h>
-#include <bits/parse_numbers.h>
+#include <bits/parse_numbers.h> // _Select_int
 #include <bits/stl_iterator_base_funcs.h>
 #include <bits/stl_construct.h>
 #include <bits/utility.h> // in_place_index_t