diff --git a/embed.fnc b/embed.fnc
index 0332f63875ec..b0510db2d229 100644
--- a/embed.fnc
+++ b/embed.fnc
@@ -2043,9 +2043,7 @@ p	|int	|mode_from_discipline					\
 				|STRLEN len
 
 : Used in sv.c and hv.c
-Cop	|void * |more_bodies	|const svtype sv_type			\
-				|const size_t body_size 		\
-				|const size_t arena_size
+Cop	|void * |more_bodies	|const svtype sv_type
 Cp	|const char *|moreswitches					\
 				|NN const char *s
 Adp	|void	|mortal_destructor_sv					\
diff --git a/hv.c b/hv.c
index 8c65091fd2ca..a62350ff4e94 100644
--- a/hv.c
+++ b/hv.c
@@ -159,7 +159,7 @@ S_new_he(pTHX)
     void ** const root = &PL_body_roots[HE_ARENA_ROOT_IX];
 
     if (!*root)
-        Perl_more_bodies(aTHX_ HE_ARENA_ROOT_IX, sizeof(HE), PERL_ARENA_SIZE);
+        Perl_more_bodies(aTHX_ HE_ARENA_ROOT_IX);
     he = (HE*) *root;
     assert(he);
     *root = HeNEXT(he);
diff --git a/proto.h b/proto.h
index e132956f8ac8..f11476f1163c 100644
--- a/proto.h
+++ b/proto.h
@@ -2555,7 +2555,7 @@ Perl_mode_from_discipline(pTHX_ const char *s, STRLEN len)
 #define PERL_ARGS_ASSERT_MODE_FROM_DISCIPLINE
 
 PERL_CALLCONV void *
-Perl_more_bodies(pTHX_ const svtype sv_type, const size_t body_size, const size_t arena_size);
+Perl_more_bodies(pTHX_ const svtype sv_type);
 #define PERL_ARGS_ASSERT_MORE_BODIES
 
 PERL_CALLCONV const char *
diff --git a/sv.c b/sv.c
index e8c6e65a2717..1ce51330cc02 100644
--- a/sv.c
+++ b/sv.c
@@ -856,10 +856,22 @@ available in hv.c. Similarly SVt_IV is re-used for HVAUX_ARENA_ROOT_IX.
 
 
 void *
-Perl_more_bodies (pTHX_ const svtype sv_type, const size_t body_size,
-                  const size_t arena_size)
+Perl_more_bodies (pTHX_ const svtype sv_type)
 {
     void ** const root = &PL_body_roots[sv_type];
+
+    const struct body_details *type_details =
+        (sv_type > SVt_IV)
+            ? bodies_by_type + sv_type
+            : (sv_type == SVt_NULL)
+                ? NULL
+                : &fake_hv_with_aux
+                ;
+
+    const size_t body_size = (type_details) ? type_details->body_size
+                                            : sizeof(HE);
+    const size_t arena_size = (type_details) ? type_details->arena_size
+                                             : PERL_ARENA_SIZE;
     struct arena_desc *adesc;
     struct arena_set *aroot = (struct arena_set *) PL_body_arenas;
     unsigned int curr;
@@ -1291,7 +1303,7 @@ Perl_hv_auxalloc(pTHX_ HV *hv) {
 #ifdef PURIFY
     new_body = new_NOARENAZ(&fake_hv_with_aux);
 #else
-    new_body_from_arena(new_body, HVAUX_ARENA_ROOT_IX, fake_hv_with_aux);
+    new_body_from_arena(new_body, HVAUX_ARENA_ROOT_IX);
 #endif
 
     old_body = SvANY(hv);
@@ -14799,7 +14811,7 @@ S_sv_dup_common(pTHX_ const SV *const ssv, CLONE_PARAMS *const param)
 #ifdef PURIFY
                     new_body = new_NOARENA(sv_type_details);
 #else
-                    new_body_from_arena(new_body, HVAUX_ARENA_ROOT_IX, fake_hv_with_aux);
+                    new_body_from_arena(new_body, HVAUX_ARENA_ROOT_IX);
 #endif
                     goto have_body;
                 }
diff --git a/sv_inline.h b/sv_inline.h
index 57a68796cb02..70153d2024aa 100644
--- a/sv_inline.h
+++ b/sv_inline.h
@@ -180,6 +180,14 @@ ALIGNED_TYPE(XPVOBJ);
         STRUCT_OFFSET(type, last_member) \
         + sizeof (((type*)SvANY((const SV *)0))->last_member)
 
+static const struct body_details fake_hv_with_aux =
+    /* The SVt_IV arena is used for (larger) PVHV bodies.  */
+    { sizeof(ALIGNED_TYPE_NAME(XPVHV_WITH_AUX)),
+      copy_length(XPVHV, xhv_max),
+      0,
+      SVt_PVHV, TRUE, NONV, HASARENA,
+      FIT_ARENA(0, sizeof(ALIGNED_TYPE_NAME(XPVHV_WITH_AUX))) };
+
 static const struct body_details bodies_by_type[] = {
     /* HEs use this offset for their arena.  */
     { 0, 0, 0, SVt_NULL, FALSE, NONV, NOARENA, 0 },
@@ -328,13 +336,11 @@ static const struct body_details bodies_by_type[] = {
 #ifndef PURIFY
 
 /* grab a new thing from the arena's free list, allocating more if necessary. */
-#define new_body_from_arena(xpv, root_index, type_meta) \
+#define new_body_from_arena(xpv, root_index) \
     STMT_START { \
         void ** const r3wt = &PL_body_roots[root_index]; \
         xpv = (PTR_TBL_ENT_t*) (*((void **)(r3wt))      \
-          ? *((void **)(r3wt)) : Perl_more_bodies(aTHX_ root_index, \
-                                             type_meta.body_size,\
-                                             type_meta.arena_size)); \
+          ? *((void **)(r3wt)) : Perl_more_bodies(aTHX_ root_index)); \
         *(r3wt) = *(void**)(xpv); \
     } STMT_END
 
@@ -342,7 +348,7 @@ PERL_STATIC_INLINE void *
 S_new_body(pTHX_ const svtype sv_type)
 {
     void *xpv;
-    new_body_from_arena(xpv, sv_type, bodies_by_type[sv_type]);
+    new_body_from_arena(xpv, sv_type);
     return xpv;
 }
 
@@ -351,14 +357,6 @@ S_new_body(pTHX_ const svtype sv_type)
 static const struct body_details fake_rv =
     { 0, 0, 0, SVt_IV, FALSE, NONV, NOARENA, 0 };
 
-static const struct body_details fake_hv_with_aux =
-    /* The SVt_IV arena is used for (larger) PVHV bodies.  */
-    { sizeof(ALIGNED_TYPE_NAME(XPVHV_WITH_AUX)),
-      copy_length(XPVHV, xhv_max),
-      0,
-      SVt_PVHV, TRUE, NONV, HASARENA,
-      FIT_ARENA(0, sizeof(ALIGNED_TYPE_NAME(XPVHV_WITH_AUX))) };
-
 /*
 =for apidoc newSV_type
 
@@ -381,6 +379,7 @@ Perl_newSV_type(pTHX_ const svtype type)
 
     SvFLAGS(sv) &= ~SVTYPEMASK;
     SvFLAGS(sv) |= type;
+//    SvFLAGS(sv) = type;
 
     switch (type) {
     case SVt_NULL: