From: Dave Mitchell <davem@fdisolutions.com>
Date: Fri, 23 Jul 2004 09:52:59 +0000 (+0000)
Subject: remove the return stack PL_retstack, and store return ops in the CX
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=f39bc417872f70cd842818eabb72f1c97d78cdd2;p=p5sagit%2Fp5-mst-13.2.git

remove the return stack PL_retstack, and store return ops in the CX
structure directly instead

p4raw-id: //depot/perl@23156
---

diff --git a/cc_runtime.h b/cc_runtime.h
index 6a1668d..3815d3a 100644
--- a/cc_runtime.h
+++ b/cc_runtime.h
@@ -54,7 +54,7 @@
 	switch (ret) {				\
 	case 0:					\
 	    PL_op = ppaddr(aTHX);		\
-	    PL_retstack[PL_retstack_ix - 1] = Nullop;	\
+	    /* XXX PL_retstack[PL_retstack_ix - 1] = Nullop;	*/ \
 	    if (PL_op != nxt) CALLRUNOPS();		\
 	    JMPENV_POP;				\
 	    break;				\
diff --git a/cop.h b/cop.h
index 9543884..16fb824 100644
--- a/cop.h
+++ b/cop.h
@@ -119,6 +119,7 @@ struct block_sub {
     U8		hasargs;
     U8		lval;		/* XXX merge lval and hasargs? */
     PAD		*oldcomppad;
+    OP *	retop;	/* op to execute on exit from sub */
 };
 
 /* base for the next two macros. Don't use directly.
@@ -129,6 +130,7 @@ struct block_sub {
 	cx->blk_sub.cv = cv;						\
 	cx->blk_sub.olddepth = CvDEPTH(cv);				\
 	cx->blk_sub.hasargs = hasargs;					\
+	cx->blk_sub.retop = Nullop;						\
 	if (!CvDEPTH(cv)) {						\
 	    (void)SvREFCNT_inc(cv);					\
 	    (void)SvREFCNT_inc(cv);					\
@@ -150,6 +152,7 @@ struct block_sub {
 #define PUSHFORMAT(cx)							\
 	cx->blk_sub.cv = cv;						\
 	cx->blk_sub.gv = gv;						\
+	cx->blk_sub.retop = Nullop;					\
 	cx->blk_sub.hasargs = 0;					\
 	cx->blk_sub.dfoutgv = PL_defoutgv;				\
 	(void)SvREFCNT_inc(cx->blk_sub.dfoutgv)
@@ -209,6 +212,7 @@ struct block_eval {
     OP *	old_eval_root;
     SV *	cur_text;
     CV *	cv;
+    OP *	retop;	/* op to execute on exit from eval */
 };
 
 #define PUSHEVAL(cx,n,fgv)						\
@@ -219,6 +223,7 @@ struct block_eval {
 	cx->blk_eval.old_eval_root = PL_eval_root;			\
 	cx->blk_eval.cur_text = PL_linestr;				\
 	cx->blk_eval.cv = Nullcv; /* set by doeval(), as applicable */	\
+	cx->blk_eval.retop = Nullop; 					\
     } STMT_END
 
 #define POPEVAL(cx)							\
@@ -298,7 +303,7 @@ struct block_loop {
 struct block {
     I32		blku_oldsp;	/* stack pointer to copy stuff down to */
     COP *	blku_oldcop;	/* old curcop pointer */
-    I32		blku_oldretsp;	/* return stack index */
+    I32		blku_SPARE1;	/* XXX for BINCOMPAT 5.8.x */
     I32		blku_oldmarksp;	/* mark stack index */
     I32		blku_oldscopesp;	/* scope stack index */
     PMOP *	blku_oldpm;	/* values of pattern match vars */
@@ -312,7 +317,6 @@ struct block {
 };
 #define blk_oldsp	cx_u.cx_blk.blku_oldsp
 #define blk_oldcop	cx_u.cx_blk.blku_oldcop
-#define blk_oldretsp	cx_u.cx_blk.blku_oldretsp
 #define blk_oldmarksp	cx_u.cx_blk.blku_oldmarksp
 #define blk_oldscopesp	cx_u.cx_blk.blku_oldscopesp
 #define blk_oldpm	cx_u.cx_blk.blku_oldpm
@@ -328,7 +332,6 @@ struct block {
 	cx->blk_oldcop		= PL_curcop,				\
 	cx->blk_oldmarksp	= PL_markstack_ptr - PL_markstack,	\
 	cx->blk_oldscopesp	= PL_scopestack_ix,			\
-	cx->blk_oldretsp	= PL_retstack_ix,			\
 	cx->blk_oldpm		= PL_curpm,				\
 	cx->blk_gimme		= (U8)gimme;				\
 	DEBUG_l( PerlIO_printf(Perl_debug_log, "Entering block %ld, type %s\n",	\
@@ -340,7 +343,6 @@ struct block {
 	PL_curcop	 = cx->blk_oldcop,				\
 	PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,		\
 	PL_scopestack_ix = cx->blk_oldscopesp,				\
-	PL_retstack_ix	 = cx->blk_oldretsp,				\
 	pm		 = cx->blk_oldpm,				\
 	gimme		 = cx->blk_gimme;				\
 	DEBUG_SCOPE("POPBLOCK");					\
@@ -352,7 +354,6 @@ struct block {
 	PL_stack_sp	 = PL_stack_base + cx->blk_oldsp,		\
 	PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,		\
 	PL_scopestack_ix = cx->blk_oldscopesp,				\
-	PL_retstack_ix	 = cx->blk_oldretsp,				\
 	PL_curpm         = cx->blk_oldpm;				\
 	DEBUG_SCOPE("TOPBLOCK");
 
diff --git a/deb.c b/deb.c
index 20fda21..f268216 100644
--- a/deb.c
+++ b/deb.c
@@ -206,9 +206,9 @@ Perl_deb_stack_all(pTHX)
 		 */
 
 		I32 i, stack_min, stack_max, mark_min, mark_max;
-		I32 ret_min, ret_max;
 		PERL_CONTEXT *cx_n;
 		PERL_SI      *si_n;
+		OP	     *retop;
 
 		cx_n = Null(PERL_CONTEXT*);
 
@@ -257,27 +257,26 @@ Perl_deb_stack_all(pTHX)
 		}
 
 		mark_min  = cx->blk_oldmarksp;
-		ret_min   = cx->blk_oldretsp;
 		if (cx_n) {
 		    mark_max  = cx_n->blk_oldmarksp;
-		    ret_max   = cx_n->blk_oldretsp;
 		}
 		else {
 		    mark_max = PL_markstack_ptr - PL_markstack;
-		    ret_max  = PL_retstack_ix;
 		}
 
 		deb_stack_n(AvARRAY(si->si_stack),
 			stack_min, stack_max, mark_min, mark_max);
 
-		if (ret_max > ret_min) {
+		if (CxTYPE(cx) == CXt_EVAL || CxTYPE(cx) == CXt_SUB
+			|| CxTYPE(cx) == CXt_FORMAT)
+		{
+		    retop = (CxTYPE(cx) == CXt_EVAL)
+			    ? cx->blk_eval.retop : cx->blk_sub.retop;
+
 		    PerlIO_printf(Perl_debug_log, "  retop=%s\n",
-			    PL_retstack[ret_min]
-				? OP_NAME(PL_retstack[ret_min])
-				: "(null)"
+			    retop ? OP_NAME(retop) : "(null)"
 		    );
 		}
-
 	    }
 	} /* next context */
 
diff --git a/mg.c b/mg.c
index 4ab7f4f..0feb7da 100644
--- a/mg.c
+++ b/mg.c
@@ -2529,8 +2529,6 @@ Perl_sighandler(int sig)
 	flags |= 1;
     if (PL_markstack_ptr < PL_markstack_max - 2)
 	flags |= 4;
-    if (PL_retstack_ix < PL_retstack_max - 2)
-	flags |= 8;
     if (PL_scopestack_ix < PL_scopestack_max - 3)
 	flags |= 16;
 
@@ -2548,10 +2546,6 @@ Perl_sighandler(int sig)
     }
     if (flags & 4)
 	PL_markstack_ptr++;		/* Protect mark. */
-    if (flags & 8) {
-	PL_retstack_ix++;
-	PL_retstack[PL_retstack_ix] = NULL;
-    }
     if (flags & 16)
 	PL_scopestack_ix += 1;
     /* sv_2cv is too complicated, try a simpler variant first: */
@@ -2612,8 +2606,6 @@ cleanup:
 	PL_savestack_ix -= 8; /* Unprotect save in progress. */
     if (flags & 4)
 	PL_markstack_ptr--;
-    if (flags & 8)
-	PL_retstack_ix--;
     if (flags & 16)
 	PL_scopestack_ix -= 1;
     if (flags & 64)
diff --git a/perl.c b/perl.c
index d818f50..99be074 100644
--- a/perl.c
+++ b/perl.c
@@ -2051,7 +2051,6 @@ Perl_call_sv(pTHX_ SV *sv, I32 flags)
 	    ENTER;
 	    SAVETMPS;
 	
-	    push_return(Nullop);
 	    PUSHBLOCK(cx, (CXt_EVAL|CXp_TRYBLOCK), PL_stack_sp);
 	    PUSHEVAL(cx, 0, 0);
 	    PL_eval_root = PL_op;             /* Only needed so that goto works right. */
@@ -2118,7 +2117,6 @@ Perl_call_sv(pTHX_ SV *sv, I32 flags)
 
 	    POPBLOCK(cx,newpm);
 	    POPEVAL(cx);
-	    pop_return();
 	    PL_curpm = newpm;
 	    LEAVE;
 	}
@@ -3891,10 +3889,6 @@ Perl_init_stacks(pTHX)
     New(54,PL_savestack,REASONABLE(128),ANY);
     PL_savestack_ix = 0;
     PL_savestack_max = REASONABLE(128);
-
-    New(54,PL_retstack,REASONABLE(16),OP*);
-    PL_retstack_ix = 0;
-    PL_retstack_max = REASONABLE(16);
 }
 
 #undef REASONABLE
@@ -3915,7 +3909,6 @@ S_nuke_stacks(pTHX)
     Safefree(PL_markstack);
     Safefree(PL_scopestack);
     Safefree(PL_savestack);
-    Safefree(PL_retstack);
 }
 
 STATIC void
diff --git a/pp_ctl.c b/pp_ctl.c
index 0c1067a..c8dd1ae 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -1434,7 +1434,8 @@ Perl_die_where(pTHX_ char *message, STRLEN msglen)
 		DIE(aTHX_ "%sCompilation failed in require",
 		    *msg ? msg : "Unknown error\n");
 	    }
-	    return pop_return();
+	    assert(CxTYPE(cx) == CXt_EVAL);
+	    return cx->blk_eval.retop;
 	}
     }
     if (!message)
@@ -1728,9 +1729,9 @@ PP(pp_dbstate)
 	hasargs = 0;
 	SPAGAIN;
 
-	push_return(PL_op->op_next);
 	PUSHBLOCK(cx, CXt_SUB, SP);
 	PUSHSUB_DB(cx);
+	cx->blk_sub.retop = PL_op->op_next;
 	CvDEPTH(cv)++;
 	PAD_SET_CUR(CvPADLIST(cv),1);
 	RETURNOP(CvSTART(cv));
@@ -1899,6 +1900,7 @@ PP(pp_return)
     PMOP *newpm;
     I32 optype = 0;
     SV *sv;
+    OP *retop;
 
     if (PL_curstackinfo->si_type == PERLSI_SORT) {
 	if (cxstack_ix == PL_sortcxix
@@ -1922,12 +1924,14 @@ PP(pp_return)
     switch (CxTYPE(cx)) {
     case CXt_SUB:
 	popsub2 = TRUE;
+	retop = cx->blk_sub.retop;
 	cxstack_ix++; /* preserve cx entry on stack for use by POPSUB */
 	break;
     case CXt_EVAL:
 	if (!(PL_in_eval & EVAL_KEEPERR))
 	    clear_errsv = TRUE;
 	POPEVAL(cx);
+	retop = cx->blk_eval.retop;
 	if (CxTRYBLOCK(cx))
 	    break;
 	lex_end();
@@ -1942,6 +1946,7 @@ PP(pp_return)
 	break;
     case CXt_FORMAT:
 	POPFORMAT(cx);
+	retop = cx->blk_sub.retop;
 	break;
     default:
 	DIE(aTHX_ "panic: return");
@@ -1995,7 +2000,7 @@ PP(pp_return)
     LEAVESUB(sv);
     if (clear_errsv)
 	sv_setpv(ERRSV,"");
-    return pop_return();
+    return retop;
 }
 
 PP(pp_last)
@@ -2036,15 +2041,15 @@ PP(pp_last)
 	break;
     case CXt_SUB:
 	pop2 = CXt_SUB;
-	nextop = pop_return();
+	nextop = cx->blk_sub.retop;
 	break;
     case CXt_EVAL:
 	POPEVAL(cx);
-	nextop = pop_return();
+	nextop = cx->blk_eval.retop;
 	break;
     case CXt_FORMAT:
 	POPFORMAT(cx);
-	nextop = pop_return();
+	nextop = cx->blk_sub.retop;
 	break;
     default:
 	DIE(aTHX_ "panic: last");
@@ -2324,7 +2329,8 @@ PP(pp_goto)
 		    /* Do _not_ use PUTBACK, keep the XSUB's return stack! */
 		}
 		LEAVE;
-		return pop_return();
+		assert(CxTYPE(cx) == CXt_SUB);
+		return cx->blk_sub.retop;
 	    }
 	    else {
 		AV* padlist = CvPADLIST(cv);
@@ -2659,8 +2665,10 @@ S_docatch(pTHX_ OP *o)
      * the op to Nullop, we force an exit from the inner runops()
      * loop. DAPM.
      */
-    retop = pop_return();
-    push_return(Nullop);
+    assert(cxstack_ix >= 0);
+    assert(CxTYPE(&cxstack[cxstack_ix]) == CXt_EVAL);
+    retop = cxstack[cxstack_ix].blk_eval.retop;
+    cxstack[cxstack_ix].blk_eval.retop = Nullop;
 
 #ifdef PERL_FLEXIBLE_EXCEPTIONS
  redo_body:
@@ -2898,7 +2906,6 @@ S_doeval(pTHX_ int gimme, OP** startop, CV* outside, U32 seq)
 	if (!startop) {
 	    POPBLOCK(cx,PL_curpm);
 	    POPEVAL(cx);
-	    pop_return();
 	}
 	lex_end();
 	LEAVE;
@@ -3356,9 +3363,9 @@ PP(pp_require)
     }
 
     /* switch to eval mode */
-    push_return(PL_op->op_next);
     PUSHBLOCK(cx, CXt_EVAL, SP);
     PUSHEVAL(cx, name, Nullgv);
+    cx->blk_eval.retop = PL_op->op_next;
 
     SAVECOPLINE(&PL_compiling);
     CopLINE_set(&PL_compiling, 0);
@@ -3449,9 +3456,9 @@ PP(pp_entereval)
      * to do the dirty work for us */
     runcv = find_runcv(&seq);
 
-    push_return(PL_op->op_next);
     PUSHBLOCK(cx, (CXt_EVAL|CXp_REAL), SP);
     PUSHEVAL(cx, 0, Nullgv);
+    cx->blk_eval.retop = PL_op->op_next;
 
     /* prepare to compile string */
 
@@ -3480,7 +3487,7 @@ PP(pp_leaveeval)
 
     POPBLOCK(cx,newpm);
     POPEVAL(cx);
-    retop = pop_return();
+    retop = cx->blk_eval.retop;
 
     TAINT_NOT;
     if (gimme == G_VOID)
@@ -3543,9 +3550,9 @@ PP(pp_entertry)
     ENTER;
     SAVETMPS;
 
-    push_return(cLOGOP->op_other->op_next);
     PUSHBLOCK(cx, (CXt_EVAL|CXp_TRYBLOCK), SP);
     PUSHEVAL(cx, 0, 0);
+    cx->blk_eval.retop = cLOGOP->op_other->op_next;
 
     PL_in_eval = EVAL_INEVAL;
     sv_setpv(ERRSV,"");
@@ -3566,7 +3573,7 @@ PP(pp_leavetry)
 
     POPBLOCK(cx,newpm);
     POPEVAL(cx);
-    retop = pop_return();
+    retop = cx->blk_eval.retop;
 
     TAINT_NOT;
     if (gimme == G_VOID)
diff --git a/pp_hot.c b/pp_hot.c
index b170b3b..752a267 100644
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -2409,7 +2409,7 @@ PP(pp_leavesub)
     PL_curpm = newpm;	/* ... and pop $1 et al */
 
     LEAVESUB(sv);
-    return pop_return();
+    return cx->blk_sub.retop;
 }
 
 /* This duplicates the above code because the above code must not
@@ -2567,7 +2567,7 @@ PP(pp_leavesublv)
     PL_curpm = newpm;	/* ... and pop $1 et al */
 
     LEAVESUB(sv);
-    return pop_return();
+    return cx->blk_sub.retop;
 }
 
 
@@ -2697,9 +2697,9 @@ PP(pp_entersub)
 	dMARK;
 	register I32 items = SP - MARK;
 	AV* padlist = CvPADLIST(cv);
-	push_return(PL_op->op_next);
 	PUSHBLOCK(cx, CXt_SUB, MARK);
 	PUSHSUB(cx);
+	cx->blk_sub.retop = PL_op->op_next;
 	CvDEPTH(cv)++;
 	/* XXX This would be a natural place to set C<PL_compcv = cv> so
 	 * that eval'' ops within this sub know the correct lexical space.
diff --git a/pp_sys.c b/pp_sys.c
index 1f19fbd..4432a47 100644
--- a/pp_sys.c
+++ b/pp_sys.c
@@ -1247,9 +1247,9 @@ S_doform(pTHX_ CV *cv, GV *gv, OP *retop)
     ENTER;
     SAVETMPS;
 
-    push_return(retop);
     PUSHBLOCK(cx, CXt_FORMAT, PL_stack_sp);
     PUSHFORMAT(cx);
+    cx->blk_sub.retop = retop;
     PAD_SET_CUR(CvPADLIST(cv), 1);
 
     setdefout(gv);	    /* locally select filehandle so $% et al work */
@@ -1425,7 +1425,7 @@ PP(pp_leavewrite)
     /* bad_ofp: */
     PL_formtarget = PL_bodytarget;
     PUTBACK;
-    return pop_return();
+    return cx->blk_sub.retop;
 }
 
 PP(pp_prtf)
diff --git a/scope.c b/scope.c
index 54d4488..8420744 100644
--- a/scope.c
+++ b/scope.c
@@ -100,23 +100,18 @@ Perl_cxinc(pTHX)
     return cxstack_ix + 1;
 }
 
+/* XXX for 5.8.X BINCOMPAT only */
 void
 Perl_push_return(pTHX_ OP *retop)
 {
-    if (PL_retstack_ix == PL_retstack_max) {
-	PL_retstack_max = GROW(PL_retstack_max);
-	Renew(PL_retstack, PL_retstack_max, OP*);
-    }
-    PL_retstack[PL_retstack_ix++] = retop;
+    Perl_croak(aTHX_ "panic: obsolete function push_return() called");
 }
 
+/* XXX for 5.8.X BINCOMPAT only */
 OP *
 Perl_pop_return(pTHX)
 {
-    if (PL_retstack_ix > 0)
-	return PL_retstack[--PL_retstack_ix];
-    else
-	return Nullop;
+    Perl_croak(aTHX_ "panic: obsolete function pop_return() called");
 }
 
 void
@@ -1098,7 +1093,6 @@ Perl_cx_dump(pTHX_ PERL_CONTEXT *cx)
 		      PTR2UV(cx->blk_oldcop));
 	PerlIO_printf(Perl_debug_log, "BLK_OLDMARKSP = %ld\n", (long)cx->blk_oldmarksp);
 	PerlIO_printf(Perl_debug_log, "BLK_OLDSCOPESP = %ld\n", (long)cx->blk_oldscopesp);
-	PerlIO_printf(Perl_debug_log, "BLK_OLDRETSP = %ld\n", (long)cx->blk_oldretsp);
 	PerlIO_printf(Perl_debug_log, "BLK_OLDPM = 0x%"UVxf"\n",
 		      PTR2UV(cx->blk_oldpm));
 	PerlIO_printf(Perl_debug_log, "BLK_GIMME = %s\n", cx->blk_gimme ? "LIST" : "SCALAR");
@@ -1116,6 +1110,8 @@ Perl_cx_dump(pTHX_ PERL_CONTEXT *cx)
 		PTR2UV(cx->blk_sub.dfoutgv));
 	PerlIO_printf(Perl_debug_log, "BLK_SUB.HASARGS = %d\n",
 		(int)cx->blk_sub.hasargs);
+	PerlIO_printf(Perl_debug_log, "BLK_SUB.RETOP = 0x%"UVxf"\n",
+		PTR2UV(cx->blk_sub.retop));
 	break;
     case CXt_SUB:
 	PerlIO_printf(Perl_debug_log, "BLK_SUB.CV = 0x%"UVxf"\n",
@@ -1126,6 +1122,8 @@ Perl_cx_dump(pTHX_ PERL_CONTEXT *cx)
 		(int)cx->blk_sub.hasargs);
 	PerlIO_printf(Perl_debug_log, "BLK_SUB.LVAL = %d\n",
 		(int)cx->blk_sub.lval);
+	PerlIO_printf(Perl_debug_log, "BLK_SUB.RETOP = 0x%"UVxf"\n",
+		PTR2UV(cx->blk_sub.retop));
 	break;
     case CXt_EVAL:
 	PerlIO_printf(Perl_debug_log, "BLK_EVAL.OLD_IN_EVAL = %ld\n",
@@ -1138,6 +1136,8 @@ Perl_cx_dump(pTHX_ PERL_CONTEXT *cx)
 			  SvPVX(cx->blk_eval.old_namesv));
 	PerlIO_printf(Perl_debug_log, "BLK_EVAL.OLD_EVAL_ROOT = 0x%"UVxf"\n",
 		PTR2UV(cx->blk_eval.old_eval_root));
+	PerlIO_printf(Perl_debug_log, "BLK_EVAL.RETOP = 0x%"UVxf"\n",
+		PTR2UV(cx->blk_eval.retop));
 	break;
 
     case CXt_LOOP:
diff --git a/sv.c b/sv.c
index 9079315..2cdebd6 100644
--- a/sv.c
+++ b/sv.c
@@ -10975,7 +10975,6 @@ Perl_cx_dup(pTHX_ PERL_CONTEXT *cxs, I32 ix, I32 max, CLONE_PARAMS* param)
 	else {
 	    ncx->blk_oldsp	= cx->blk_oldsp;
 	    ncx->blk_oldcop	= cx->blk_oldcop;
-	    ncx->blk_oldretsp	= cx->blk_oldretsp;
 	    ncx->blk_oldmarksp	= cx->blk_oldmarksp;
 	    ncx->blk_oldscopesp	= cx->blk_oldscopesp;
 	    ncx->blk_oldpm	= cx->blk_oldpm;
@@ -10992,6 +10991,7 @@ Perl_cx_dup(pTHX_ PERL_CONTEXT *cxs, I32 ix, I32 max, CLONE_PARAMS* param)
 		ncx->blk_sub.olddepth	= cx->blk_sub.olddepth;
 		ncx->blk_sub.hasargs	= cx->blk_sub.hasargs;
 		ncx->blk_sub.lval	= cx->blk_sub.lval;
+		ncx->blk_sub.retop	= cx->blk_sub.retop;
 		break;
 	    case CXt_EVAL:
 		ncx->blk_eval.old_in_eval = cx->blk_eval.old_in_eval;
@@ -10999,6 +10999,7 @@ Perl_cx_dup(pTHX_ PERL_CONTEXT *cxs, I32 ix, I32 max, CLONE_PARAMS* param)
 		ncx->blk_eval.old_namesv = sv_dup_inc(cx->blk_eval.old_namesv, param);
 		ncx->blk_eval.old_eval_root = cx->blk_eval.old_eval_root;
 		ncx->blk_eval.cur_text	= sv_dup(cx->blk_eval.cur_text, param);
+		ncx->blk_eval.retop = cx->blk_eval.retop;
 		break;
 	    case CXt_LOOP:
 		ncx->blk_loop.label	= cx->blk_loop.label;
@@ -11023,6 +11024,7 @@ Perl_cx_dup(pTHX_ PERL_CONTEXT *cxs, I32 ix, I32 max, CLONE_PARAMS* param)
 		ncx->blk_sub.gv		= gv_dup(cx->blk_sub.gv, param);
 		ncx->blk_sub.dfoutgv	= gv_dup_inc(cx->blk_sub.dfoutgv, param);
 		ncx->blk_sub.hasargs	= cx->blk_sub.hasargs;
+		ncx->blk_sub.retop	= cx->blk_sub.retop;
 		break;
 	    case CXt_BLOCK:
 	    case CXt_NULL:
@@ -11472,7 +11474,6 @@ perl_clone_using(PerlInterpreter *proto_perl, UV flags,
     PL_savestack = 0;
     PL_savestack_ix = 0;
     PL_savestack_max = -1;
-    PL_retstack = 0;
     PL_sig_pending = 0;
     Zero(&PL_debug_pad, 1, struct perl_debug_pad);
 #  else	/* !DEBUGGING */
@@ -11505,7 +11506,6 @@ perl_clone_using(PerlInterpreter *proto_perl, UV flags,
     PL_savestack = 0;
     PL_savestack_ix = 0;
     PL_savestack_max = -1;
-    PL_retstack = 0;
     PL_sig_pending = 0;
     Zero(&PL_debug_pad, 1, struct perl_debug_pad);
 #    else	/* !DEBUGGING */
@@ -12043,13 +12043,6 @@ perl_clone_using(PerlInterpreter *proto_perl, UV flags,
 	Newz(54, PL_scopestack, PL_scopestack_max, I32);
 	Copy(proto_perl->Tscopestack, PL_scopestack, PL_scopestack_ix, I32);
 
-	/* next push_return() sets PL_retstack[PL_retstack_ix]
-	 * NOTE: unlike the others! */
-	PL_retstack_ix		= proto_perl->Tretstack_ix;
-	PL_retstack_max		= proto_perl->Tretstack_max;
-	Newz(54, PL_retstack, PL_retstack_max, OP*);
-	Copy(proto_perl->Tretstack, PL_retstack, PL_retstack_ix, OP*);
-
 	/* NOTE: si_dup() looks at PL_markstack */
 	PL_curstackinfo		= si_dup(proto_perl->Tcurstackinfo, param);
 
diff --git a/thrdvar.h b/thrdvar.h
index da80ab4..ede3cc1 100644
--- a/thrdvar.h
+++ b/thrdvar.h
@@ -56,9 +56,9 @@ PERLVAR(Tmarkstack,	I32 *)		/* stack_sp locations we're remembering */
 PERLVAR(Tmarkstack_ptr,	I32 *)
 PERLVAR(Tmarkstack_max,	I32 *)
 
-PERLVAR(Tretstack,	OP **)		/* OPs we have postponed executing */
-PERLVAR(Tretstack_ix,	I32)
-PERLVAR(Tretstack_max,	I32)
+PERLVAR(Tretstack,	OP **)		/* XXX for 5.8.x BINCOMPAT */
+PERLVAR(Tretstack_ix,	I32)		/* XXX for 5.8.x BINCOMPAT */
+PERLVAR(Tretstack_max,	I32)		/* XXX for 5.8.x BINCOMPAT */
 
 PERLVAR(TSv,		SV *)		/* used to hold temporary values */
 PERLVAR(TXpv,		XPV *)		/* used to hold temporary values */