glib/gdatetime.c: In function ‘get_iso8601_int’:
glib/gdatetime.c:1142:17: error: comparison of integer expressions of different signedness: ‘gint’ {aka ‘int’} and ‘gsize’ {aka ‘long unsigned int’} [-Werror=sign-compare]
   for (i = 0; i < length; i++)
                 ^
glib/gdatetime.c: In function ‘get_iso8601_seconds’:
glib/gdatetime.c:1175:9: error: comparison of integer expressions of different signedness: ‘gint’ {aka ‘int’} and ‘gsize’ {aka ‘long unsigned int’} [-Werror=sign-compare]
   if (i == length)
         ^~
glib/gdatetime.c:1178:12: error: comparison of integer expressions of different signedness: ‘gint’ {aka ‘int’} and ‘gsize’ {aka ‘long unsigned int’} [-Werror=sign-compare]
   for (; i < length; i++)
            ^
In file included from glib/glibconfig.h:9,
                 from glib/gtypes.h:32,
                 from glib/gtimezone.h:27,
                 from glib/gdatetime.h:31,
                 from glib/gdatetime.c:62:
glib/gdatetime.c: In function ‘initialize_alt_digits’:
glib/gdatetime.c:2806:27: error: comparison of integer expressions of different signedness: ‘gsize’ {aka ‘long unsigned int’} and ‘long int’ [-Werror=sign-compare]
       g_assert (digit_len < buffer + sizeof (buffer) - buffer_end);
                           ^
glib/gmacros.h:455:25: note: in definition of macro ‘G_LIKELY’
 #define G_LIKELY(expr) (expr)
                         ^~~~
glib/gdatetime.c:2806:7: note: in expansion of macro ‘g_assert’
       g_assert (digit_len < buffer + sizeof (buffer) - buffer_end);
       ^~~~~~~~