Get mad compiling as C++. (At least for me)

p4raw-id: //depot/perl@31933

1 files changed, 1 insertions, 1 deletions

diff --git a/op.c b/op.c
index d3fabf35b8..05ddc86cc8 100644
--- a/op.c
+++ b/op.c
@@ -2818,7 +2818,7 @@ Perl_newMADsv(pTHX_ char key, SV* sv)
 }
 
 MADPROP *
-Perl_newMADPROP(pTHX_ char key, char type, void* val, I32 vlen)
+Perl_newMADPROP(pTHX_ char key, char type, const void* val, I32 vlen)
 {
     MADPROP *mp;
     Newxz(mp, 1, MADPROP);