+#ifndef SvRV_const
+# define SvRV_const(sv) SvRV((SV *) sv)
+#endif
+
+#ifndef SvREFCNT_inc_simple_void
+# define SvREFCNT_inc_simple_void(sv) ((void) SvREFCNT_inc(sv))
+#endif
+
+#ifndef mPUSHu
+# define mPUSHu(U) PUSHs(sv_2mortal(newSVuv(U)))
+#endif
+
+#ifndef PERL_MAGIC_ext
+# define PERL_MAGIC_ext '~'
+#endif
+
+#ifndef PERL_MAGIC_tied
+# define PERL_MAGIC_tied 'P'
+#endif
+
+#ifndef MGf_LOCAL
+# define MGf_LOCAL 0
+#endif
+
+#ifndef IN_PERL_COMPILETIME
+# define IN_PERL_COMPILETIME (PL_curcop == &PL_compiling)
+#endif
+
+/* uvar magic and Hash::Util::FieldHash were commited with 28419, but we only
+ * enable them on 5.10 */
+#if VMG_HAS_PERL(5, 10, 0)
+# define VMG_UVAR 1
+#else
+# define VMG_UVAR 0
+#endif
+
+#if VMG_HAS_PERL_MAINT(5, 11, 0, 32969) || VMG_HAS_PERL(5, 12, 0)
+# define VMG_COMPAT_SCALAR_LENGTH_NOLEN 1
+#else
+# define VMG_COMPAT_SCALAR_LENGTH_NOLEN 0
+#endif
+
+/* Applied to dev-5.9 as 25854, integrated to maint-5.8 as 28160, partially
+ * reverted to dev-5.11 as 9cdcb38b */
+#if VMG_HAS_PERL_MAINT(5, 8, 9, 28160) || VMG_HAS_PERL_MAINT(5, 9, 3, 25854) || VMG_HAS_PERL(5, 10, 0)
+# ifndef VMG_COMPAT_ARRAY_PUSH_NOLEN
+# if VMG_HAS_PERL(5, 11, 0)
+# define VMG_COMPAT_ARRAY_PUSH_NOLEN 0
+# else
+# define VMG_COMPAT_ARRAY_PUSH_NOLEN 1
+# endif
+# endif
+# ifndef VMG_COMPAT_ARRAY_PUSH_NOLEN_VOID
+# define VMG_COMPAT_ARRAY_PUSH_NOLEN_VOID 1
+# endif
+#else
+# ifndef VMG_COMPAT_ARRAY_PUSH_NOLEN
+# define VMG_COMPAT_ARRAY_PUSH_NOLEN 0
+# endif
+# ifndef VMG_COMPAT_ARRAY_PUSH_NOLEN_VOID
+# define VMG_COMPAT_ARRAY_PUSH_NOLEN_VOID 0
+# endif
+#endif
+
+/* Applied to dev-5.11 as 34908 */
+#if VMG_HAS_PERL_MAINT(5, 11, 0, 34908) || VMG_HAS_PERL(5, 12, 0)
+# define VMG_COMPAT_ARRAY_UNSHIFT_NOLEN_VOID 1
+#else
+# define VMG_COMPAT_ARRAY_UNSHIFT_NOLEN_VOID 0
+#endif
+
+/* Applied to dev-5.9 as 31473 (see #43357), integrated to maint-5.8 as 32542 */
+#if VMG_HAS_PERL_MAINT(5, 8, 9, 32542) || VMG_HAS_PERL_MAINT(5, 9, 5, 31473) || VMG_HAS_PERL(5, 10, 0)
+# define VMG_COMPAT_ARRAY_UNDEF_CLEAR 1
+#else
+# define VMG_COMPAT_ARRAY_UNDEF_CLEAR 0
+#endif
+
+#if VMG_HAS_PERL(5, 11, 0)
+# define VMG_COMPAT_HASH_DELETE_NOUVAR_VOID 1
+#else
+# define VMG_COMPAT_HASH_DELETE_NOUVAR_VOID 0
+#endif
+
+#if VMG_HAS_PERL(5, 13, 2)
+# define VMG_COMPAT_GLOB_GET 1
+#else
+# define VMG_COMPAT_GLOB_GET 0
+#endif
+
+/* ... Bug-free mg_magical ................................................. */
+
+/* See the discussion at http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2008-01/msg00036.html */
+
+#if VMG_HAS_PERL(5, 11, 3)
+
+#define vmg_mg_magical(S) mg_magical(S)
+
+#else
+
+STATIC void vmg_mg_magical(SV *sv) {
+ const MAGIC *mg;
+
+ SvMAGICAL_off(sv);
+ if ((mg = SvMAGIC(sv))) {
+ do {
+ const MGVTBL* const vtbl = mg->mg_virtual;
+ if (vtbl) {
+ if (vtbl->svt_get && !(mg->mg_flags & MGf_GSKIP))
+ SvGMAGICAL_on(sv);
+ if (vtbl->svt_set)
+ SvSMAGICAL_on(sv);
+ if (vtbl->svt_clear)
+ SvRMAGICAL_on(sv);
+ }
+ } while ((mg = mg->mg_moremagic));
+ if (!(SvFLAGS(sv) & (SVs_GMG|SVs_SMG)))
+ SvRMAGICAL_on(sv);
+ }
+}
+