#define PERL_MAGIC_uvar 'U' /* Available for use by extensions */
#define PERL_MAGIC_uvar_elem 'u' /* Reserved for use by extensions */
#define PERL_MAGIC_vec 'v' /* vec() lvalue */
+#define PERL_MAGIC_vstring 'V' /* SV was vstring literal */
#define PERL_MAGIC_substr 'x' /* substr() lvalue */
#define PERL_MAGIC_defelem 'y' /* Shadow "foreach" iterator variable /
smart parameter vivification */