include: add comment why our sys/mount.h does not include the one by glibc

diff --git a/src/basic/include/sys/mount.h b/src/basic/include/sys/mount.h
index c79160aff472a6728b2706fcf739ffca762dc199..9e7d3d74f1bf6aa44806d2d6cda76d7e690fbcf4 100644 (file)
--- a/src/basic/include/sys/mount.h
+++ b/src/basic/include/sys/mount.h
@@ -13,6 +13,12 @@
 #include "missing_fs.h"
 #include "missing_syscall_def.h"
 
+/* Since glibc-2.37 (774058d72942249f71d74e7f2b639f77184160a6), sys/mount.h includes linux/mount.h, and
+ * we can safely include both headers in the same source file. However, we cannot do that with older glibc.
+ * To avoid conflicts, let's not use glibc's sys/mount.h, and provide our own minimal implementation.
+ * Fortunately, most of definitions we need are covered by linux/fs.h and linux/mount.h, so only one enum
+ * and a few function prototypes need to be defined here. */
+
 /* Possible value for FLAGS parameter of `umount2'.  */
 enum
 {