3 files changed, 11 insertions, 12 deletions
diff --git a/embed.fnc b/embed.fnc
index 45f3a927dc..4b37eac6e4 100644
--- a/embed.fnc
+++ b/embed.fnc
@@ -985,8 +985,8 @@ Apa	|PerlIO*|fp_dup		|NULLOK PerlIO* fp|char type|NN CLONE_PARAMS* param
 Apa	|DIR*	|dirp_dup	|NULLOK DIR* dp
 Apa	|GP*	|gp_dup		|NULLOK GP* gp|NN CLONE_PARAMS* param
 Apa	|MAGIC*	|mg_dup		|NULLOK MAGIC* mg|NN CLONE_PARAMS* param
-Apa	|SV*	|sv_dup		|NULLOK SV* sstr|NN CLONE_PARAMS* param
-Ap	|void	|rvpv_dup	|NN SV* dstr|NN SV *sstr|NN CLONE_PARAMS* param
+Apa	|SV*	|sv_dup		|NULLOK const SV* sstr|NN CLONE_PARAMS* param
+Ap	|void	|rvpv_dup	|NN SV* dstr|NN const SV *sstr|NN CLONE_PARAMS* param
 Apa	|PTR_TBL_t*|ptr_table_new
 Apa	|void*	|ptr_table_fetch|NN PTR_TBL_t *tbl|NN const void *sv
 Ap	|void	|ptr_table_store|NN PTR_TBL_t *tbl|NULLOK const void *oldsv|NN void *newsv
diff --git a/proto.h b/proto.h
index 3a265d767a..4c53afb56f 100644
--- a/proto.h
+++ b/proto.h
@@ -2765,12 +2765,12 @@ PERL_CALLCONV MAGIC*	Perl_mg_dup(pTHX_ MAGIC* mg, CLONE_PARAMS* param)
 			__attribute__warn_unused_result__
 			__attribute__nonnull__(pTHX_2);
 
-PERL_CALLCONV SV*	Perl_sv_dup(pTHX_ SV* sstr, CLONE_PARAMS* param)
+PERL_CALLCONV SV*	Perl_sv_dup(pTHX_ const SV* sstr, CLONE_PARAMS* param)
 			__attribute__malloc__
 			__attribute__warn_unused_result__
 			__attribute__nonnull__(pTHX_2);
 
-PERL_CALLCONV void	Perl_rvpv_dup(pTHX_ SV* dstr, SV *sstr, CLONE_PARAMS* param)
+PERL_CALLCONV void	Perl_rvpv_dup(pTHX_ SV* dstr, const SV *sstr, CLONE_PARAMS* param)
 			__attribute__nonnull__(pTHX_1)
 			__attribute__nonnull__(pTHX_2)
 			__attribute__nonnull__(pTHX_3);
diff --git a/sv.c b/sv.c
index 781222ea1e..8f3e9cd220 100644
--- a/sv.c
+++ b/sv.c
@@ -9179,7 +9179,7 @@ Perl_ptr_table_free(pTHX_ PTR_TBL_t *tbl)
 
 
 void
-Perl_rvpv_dup(pTHX_ SV *dstr, SV *sstr, CLONE_PARAMS* param)
+Perl_rvpv_dup(pTHX_ SV *dstr, const SV *sstr, CLONE_PARAMS* param)
 {
     if (SvROK(sstr)) {
 	SvRV_set(dstr, SvWEAKREF(sstr)
@@ -9225,7 +9225,7 @@ Perl_rvpv_dup(pTHX_ SV *dstr, SV *sstr, CLONE_PARAMS* param)
 /* duplicate an SV of any type (including AV, HV etc) */
 
 SV *
-Perl_sv_dup(pTHX_ SV *sstr, CLONE_PARAMS* param)
+Perl_sv_dup(pTHX_ const SV *sstr, CLONE_PARAMS* param)
 {
     dVAR;
     SV *dstr;
@@ -9240,12 +9240,11 @@ Perl_sv_dup(pTHX_ SV *sstr, CLONE_PARAMS* param)
     if(param->flags & CLONEf_JOIN_IN) {
         /** We are joining here so we don't want do clone
 	    something that is bad **/
-	const char *hvname;
-
-        if(SvTYPE(sstr) == SVt_PVHV &&
-	   (hvname = HvNAME_get(sstr))) {
-	    /** don't clone stashes if they already exist **/
-	    return (SV*)gv_stashpv(hvname,0);
+	if (SvTYPE(sstr) == SVt_PVHV) {
+	    const char * const hvname = HvNAME_get(sstr);
+	    if (hvname)
+		/** don't clone stashes if they already exist **/
+		return (SV*)gv_stashpv(hvname,0);
         }
     }