1 files changed, 15 insertions, 3 deletions

diff --git a/gl/hard-locale.h b/gl/hard-locale.h
index 880c9e85..5d40e522 100644
--- a/gl/hard-locale.h
+++ b/gl/hard-locale.h
@@ -1,6 +1,6 @@
 /* Determine whether a locale is hard.
 
-   Copyright (C) 1999, 2003-2004, 2009-2023 Free Software Foundation, Inc.
+   Copyright (C) 1999, 2003-2004, 2009-2024 Free Software Foundation, Inc.
 
    This file is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as
@@ -16,11 +16,23 @@
    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
 
 #ifndef HARD_LOCALE_H_
-# define HARD_LOCALE_H_ 1
+#define HARD_LOCALE_H_ 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 
 /* Return true if the specified CATEGORY of the current locale is hard, i.e.
    different from the C or POSIX locale that has a fixed behavior.
-   CATEGORY must be one of the LC_* values, but not LC_ALL.  */
+   CATEGORY must be one of the LC_* values, but not LC_ALL.
+   Note: This function uses the current global locale; it ignores the
+   per-thread locale.  */
 extern bool hard_locale (int category);
 
+
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* HARD_LOCALE_H_ */