diff --git a/headers/posix/limits.h b/headers/posix/limits.h
index e88187ac21..37e68d0a72 100644
--- a/headers/posix/limits.h
+++ b/headers/posix/limits.h
@@ -114,6 +114,7 @@
 #define _POSIX2_BC_DIM_MAX		(2048)
 #define _POSIX2_BC_SCALE_MAX	(99)
 #define _POSIX2_BC_STRING_MAX	(1000)
+#define _POSIX2_CHARCLASS_NAME_MAX (14)
 #define _POSIX2_COLL_WEIGHTS_MAX (2)
 #define _POSIX2_EXPR_NEST_MAX	(32)
 #define _POSIX2_LINE_MAX		(2048)