Fix expected constness for utf8_length() arguments

diff --git a/Magic.xs b/Magic.xs
index e55503a9d64991e68971152b1d016f6feb96b700..f64d001f5efef803452f63eb2cc4ae0280885708 100644 (file)
--- a/Magic.xs
+++ b/Magic.xs
@@ -104,10 +104,6 @@ STATIC SV *vmg_clone(pTHX_ SV *sv, tTHX owner) {
 # define mPUSHu(U) PUSHs(sv_2mortal(newSVuv(U)))
 #endif
 
-#ifndef SvPV_const
-# define SvPV_const SvPV
-#endif
-
 #ifndef PERL_MAGIC_ext
 # define PERL_MAGIC_ext '~'
 #endif
@@ -988,7 +984,11 @@ STATIC U32 vmg_svt_len(pTHX_ SV *sv, MAGIC *mg) {
  PUSHs(mg->mg_obj ? mg->mg_obj : &PL_sv_undef);
  if (t < SVt_PVAV) {
   STRLEN l;
-  const U8 *s = (const U8 *) SvPV_const(sv, l);
+#if VMG_HAS_PERL(5, 9, 2)
+  const U8 *s = SvPV_const(sv, l);
+#else
+  U8 *s = SvPV(sv, l);
+#endif
   if (DO_UTF8(sv))
    len = utf8_length(s, s + l);
   else