X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=op.c;h=caf1d8433d4e95c50a356cca53c147a75c4156c6;hb=5c144d81801caa5e8317f6a38b40eb08257c47ea;hp=02d4f17c88f50b2763e62ceaff6d6e4edf3fb908;hpb=1cb0ed9b77e4ba2e0bcbeb9a897574a0fe3f3e52;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/op.c b/op.c
index 02d4f17..caf1d84 100644
--- a/op.c
+++ b/op.c
@@ -190,14 +190,14 @@ S_too_many_arguments(pTHX_ OP *o, const char *name)
 }
 
 STATIC void
-S_bad_type(pTHX_ I32 n, const char *t, const char *name, OP *kid)
+S_bad_type(pTHX_ I32 n, const char *t, const char *name, const OP *kid)
 {
     yyerror(Perl_form(aTHX_ "Type of arg %d to %s must be %s (not %s)",
 		 (int)n, name, t, OP_DESC(kid)));
 }
 
 STATIC void
-S_no_bareword_allowed(pTHX_ OP *o)
+S_no_bareword_allowed(pTHX_ const OP *o)
 {
     qerror(Perl_mess(aTHX_
 		     "Bareword \"%"SVf"\" not allowed while \"strict subs\" in use",
@@ -270,7 +270,7 @@ Perl_allocmy(pTHX_ char *name)
 void
 Perl_op_free(pTHX_ OP *o)
 {
-    register OP *kid, *nextkid;
+    dVAR;
     OPCODE type;
     PADOFFSET refcnt;
 
@@ -297,6 +297,7 @@ Perl_op_free(pTHX_ OP *o)
     }
 
     if (o->op_flags & OPf_KIDS) {
+        register OP *kid, *nextkid;
 	for (kid = cUNOPo->op_first; kid; kid = nextkid) {
 	    nextkid = kid->op_sibling; /* Get before next freeing kid */
 	    op_free(kid);
@@ -313,12 +314,17 @@ Perl_op_free(pTHX_ OP *o)
 
     op_clear(o);
     FreeOp(o);
+#ifdef DEBUG_LEAKING_SCALARS
+    if (PL_op == o)
+	PL_op = Nullop;
+#endif
 }
 
 void
 Perl_op_clear(pTHX_ OP *o)
 {
 
+    dVAR;
     switch (o->op_type) {
     case OP_NULL:	/* Was holding old type, if any. */
     case OP_ENTEREVAL:	/* Was holding hints. */
@@ -401,18 +407,21 @@ clear_pmop:
 	{
 	    HV *pmstash = PmopSTASH(cPMOPo);
 	    if (pmstash && SvREFCNT(pmstash)) {
-		PMOP *pmop = HvPMROOT(pmstash);
-		PMOP *lastpmop = NULL;
-		while (pmop) {
-		    if (cPMOPo == pmop) {
-			if (lastpmop)
-			    lastpmop->op_pmnext = pmop->op_pmnext;
-			else
-			    HvPMROOT(pmstash) = pmop->op_pmnext;
-			break;
+		MAGIC *mg = mg_find((SV*)pmstash, PERL_MAGIC_symtab);
+		if (mg) {
+		    PMOP *pmop = (PMOP*) mg->mg_obj;
+		    PMOP *lastpmop = NULL;
+		    while (pmop) {
+			if (cPMOPo == pmop) {
+			    if (lastpmop)
+				lastpmop->op_pmnext = pmop->op_pmnext;
+			    else
+				mg->mg_obj = (SV*) pmop->op_pmnext;
+			    break;
+			}
+			lastpmop = pmop;
+			pmop = pmop->op_pmnext;
 		    }
-		    lastpmop = pmop;
-		    pmop = pmop->op_pmnext;
 		}
 	    }
 	    PmopSTASH_free(cPMOPo);
@@ -467,6 +476,7 @@ S_cop_free(pTHX_ COP* cop)
 void
 Perl_op_null(pTHX_ OP *o)
 {
+    dVAR;
     if (o->op_type == OP_NULL)
 	return;
     op_clear(o);
@@ -478,12 +488,14 @@ Perl_op_null(pTHX_ OP *o)
 void
 Perl_op_refcnt_lock(pTHX)
 {
+    dVAR;
     OP_REFCNT_LOCK;
 }
 
 void
 Perl_op_refcnt_unlock(pTHX)
 {
+    dVAR;
     OP_REFCNT_UNLOCK;
 }
 
@@ -494,13 +506,13 @@ Perl_op_refcnt_unlock(pTHX)
 OP *
 Perl_linklist(pTHX_ OP *o)
 {
-    register OP *kid;
 
     if (o->op_next)
 	return o->op_next;
 
     /* establish postfix order */
     if (cUNOPo->op_first) {
+        register OP *kid;
 	o->op_next = LINKLIST(cUNOPo->op_first);
 	for (kid = cUNOPo->op_first; kid; kid = kid->op_sibling) {
 	    if (kid->op_sibling)
@@ -531,7 +543,7 @@ S_scalarboolean(pTHX_ OP *o)
 {
     if (o->op_type == OP_SASSIGN && cBINOPo->op_first->op_type == OP_CONST) {
 	if (ckWARN(WARN_SYNTAX)) {
-	    line_t oldline = CopLINE(PL_curcop);
+	    const line_t oldline = CopLINE(PL_curcop);
 
 	    if (PL_copline != NOLINE)
 		CopLINE_set(PL_curcop, PL_copline);
@@ -545,6 +557,7 @@ S_scalarboolean(pTHX_ OP *o)
 OP *
 Perl_scalar(pTHX_ OP *o)
 {
+    dVAR;
     OP *kid;
 
     /* assumes no premature commitment */
@@ -615,6 +628,7 @@ Perl_scalar(pTHX_ OP *o)
 OP *
 Perl_scalarvoid(pTHX_ OP *o)
 {
+    dVAR;
     OP *kid;
     const char* useless = 0;
     SV* sv;
@@ -771,9 +785,9 @@ Perl_scalarvoid(pTHX_ OP *o)
                      built upon these three nroff macros being used in
                      void context. The pink camel has the details in
                      the script wrapman near page 319. */
-		    if (strnEQ(SvPVX(sv), "di", 2) ||
-			strnEQ(SvPVX(sv), "ds", 2) ||
-			strnEQ(SvPVX(sv), "ig", 2))
+		    if (strnEQ(SvPVX_const(sv), "di", 2) ||
+			strnEQ(SvPVX_const(sv), "ds", 2) ||
+			strnEQ(SvPVX_const(sv), "ig", 2))
 			    useless = 0;
 		}
 	    }
@@ -843,8 +857,8 @@ Perl_scalarvoid(pTHX_ OP *o)
 OP *
 Perl_listkids(pTHX_ OP *o)
 {
-    OP *kid;
     if (o && o->op_flags & OPf_KIDS) {
+        OP *kid;
 	for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
 	    list(kid);
     }
@@ -854,6 +868,7 @@ Perl_listkids(pTHX_ OP *o)
 OP *
 Perl_list(pTHX_ OP *o)
 {
+    dVAR;
     OP *kid;
 
     /* assumes no premature commitment */
@@ -929,14 +944,13 @@ Perl_list(pTHX_ OP *o)
 OP *
 Perl_scalarseq(pTHX_ OP *o)
 {
-    OP *kid;
-
     if (o) {
 	if (o->op_type == OP_LINESEQ ||
 	     o->op_type == OP_SCOPE ||
 	     o->op_type == OP_LEAVE ||
 	     o->op_type == OP_LEAVETRY)
 	{
+            OP *kid;
 	    for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling) {
 		if (kid->op_sibling) {
 		    scalarvoid(kid);
@@ -956,8 +970,8 @@ Perl_scalarseq(pTHX_ OP *o)
 STATIC OP *
 S_modkids(pTHX_ OP *o, I32 type)
 {
-    OP *kid;
     if (o && o->op_flags & OPf_KIDS) {
+        OP *kid;
 	for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
 	    mod(kid, type);
     }
@@ -978,6 +992,7 @@ S_modkids(pTHX_ OP *o, I32 type)
 OP *
 Perl_mod(pTHX_ OP *o, I32 type)
 {
+    dVAR;
     OP *kid;
     /* -1 = error on localize, 0 = ignore localize, 1 = ok to localize */
     int localize = -1;
@@ -1317,7 +1332,7 @@ Perl_mod(pTHX_ OP *o, I32 type)
 }
 
 STATIC bool
-S_scalar_mod_type(pTHX_ OP *o, I32 type)
+S_scalar_mod_type(pTHX_ const OP *o, I32 type)
 {
     switch (type) {
     case OP_SASSIGN:
@@ -1364,12 +1379,12 @@ S_scalar_mod_type(pTHX_ OP *o, I32 type)
 }
 
 STATIC bool
-S_is_handle_constructor(pTHX_ OP *o, I32 argnum)
+S_is_handle_constructor(pTHX_ const OP *o, I32 numargs)
 {
     switch (o->op_type) {
     case OP_PIPE_OP:
     case OP_SOCKPAIR:
-	if (argnum == 2)
+	if (numargs == 2)
 	    return TRUE;
 	/* FALL THROUGH */
     case OP_SYSOPEN:
@@ -1378,7 +1393,7 @@ S_is_handle_constructor(pTHX_ OP *o, I32 argnum)
     case OP_SOCKET:
     case OP_OPEN_DIR:
     case OP_ACCEPT:
-	if (argnum == 1)
+	if (numargs == 1)
 	    return TRUE;
 	/* FALL THROUGH */
     default:
@@ -1389,8 +1404,8 @@ S_is_handle_constructor(pTHX_ OP *o, I32 argnum)
 OP *
 Perl_refkids(pTHX_ OP *o, I32 type)
 {
-    OP *kid;
     if (o && o->op_flags & OPf_KIDS) {
+        OP *kid;
 	for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
 	    ref(kid, type);
     }
@@ -1400,6 +1415,7 @@ Perl_refkids(pTHX_ OP *o, I32 type)
 OP *
 Perl_ref(pTHX_ OP *o, I32 type)
 {
+    dVAR;
     OP *kid;
 
     if (!o || PL_error_count)
@@ -1512,23 +1528,20 @@ S_dup_attrlist(pTHX_ OP *o)
 STATIC void
 S_apply_attrs(pTHX_ HV *stash, SV *target, OP *attrs, bool for_my)
 {
+    dVAR;
     SV *stashsv;
 
     /* fake up C<use attributes $pkg,$rv,@attrs> */
     ENTER;		/* need to protect against side-effects of 'use' */
     SAVEINT(PL_expect);
-    if (stash)
-	stashsv = newSVpv(HvNAME(stash), 0);
-    else
-	stashsv = &PL_sv_no;
+    stashsv = stash ? newSVhek(HvNAME_HEK(stash)) : &PL_sv_no;
 
 #define ATTRSMODULE "attributes"
 #define ATTRSMODULE_PM "attributes.pm"
 
     if (for_my) {
-	SV **svp;
 	/* Don't force the C<use> if we don't need it. */
-	svp = hv_fetch(GvHVn(PL_incgv), ATTRSMODULE_PM,
+	SV **svp = hv_fetch(GvHVn(PL_incgv), ATTRSMODULE_PM,
 		       sizeof(ATTRSMODULE_PM)-1, 0);
 	if (svp && *svp != &PL_sv_undef)
 	    ; 		/* already in %INC */
@@ -1571,10 +1584,8 @@ S_apply_attrs_my(pTHX_ HV *stash, OP *target, OP *attrs, OP **imopsp)
     pack = newSVOP(OP_CONST, 0, newSVpvn(ATTRSMODULE, sizeof(ATTRSMODULE)-1));
 
     /* Build up the real arg-list. */
-    if (stash)
-	stashsv = newSVpv(HvNAME(stash), 0);
-    else
-	stashsv = &PL_sv_no;
+    stashsv = stash ? newSVhek(HvNAME_HEK(stash)) : &PL_sv_no;
+
     arg = newOP(OP_PADSV, 0);
     arg->op_targ = target->op_targ;
     arg = prepend_elem(OP_LIST,
@@ -1586,9 +1597,13 @@ S_apply_attrs_my(pTHX_ HV *stash, OP *target, OP *attrs, OP **imopsp)
 
     /* Fake up a method call to import */
     meth = newSVpvn("import", 6);
-    (void)SvUPGRADE(meth, SVt_PVIV);
+    SvUPGRADE(meth, SVt_PVIV);
     (void)SvIOK_on(meth);
-    PERL_HASH(SvUVX(meth), SvPVX(meth), SvCUR(meth));
+    {
+	U32 hash;
+	PERL_HASH(hash, SvPVX_const(meth), SvCUR(meth));
+	SvUV_set(meth, hash);
+    }
     imop = convert(OP_ENTERSUB, OPf_STACKED|OPf_SPECIAL|OPf_WANT_VOID,
 		   append_elem(OP_LIST,
 			       prepend_elem(OP_LIST, pack, list(arg)),
@@ -1617,8 +1632,8 @@ to respect attribute syntax properly would be welcome.
 */
 
 void
-Perl_apply_attrs_string(pTHX_ char *stashpv, CV *cv,
-                        char *attrstr, STRLEN len)
+Perl_apply_attrs_string(pTHX_ const char *stashpv, CV *cv,
+                        const char *attrstr, STRLEN len)
 {
     OP *attrs = Nullop;
 
@@ -1629,7 +1644,7 @@ Perl_apply_attrs_string(pTHX_ char *stashpv, CV *cv,
     while (len) {
         for (; isSPACE(*attrstr) && len; --len, ++attrstr) ;
         if (len) {
-            char *sstr = attrstr;
+            const char *sstr = attrstr;
             for (; !isSPACE(*attrstr) && len; --len, ++attrstr) ;
             attrs = append_elem(OP_LIST, attrs,
                                 newSVOP(OP_CONST, 0,
@@ -1650,7 +1665,6 @@ Perl_apply_attrs_string(pTHX_ char *stashpv, CV *cv,
 STATIC OP *
 S_my_kid(pTHX_ OP *o, OP *attrs, OP **imopsp)
 {
-    OP *kid;
     I32 type;
 
     if (!o || PL_error_count)
@@ -1658,6 +1672,7 @@ S_my_kid(pTHX_ OP *o, OP *attrs, OP **imopsp)
 
     type = o->op_type;
     if (type == OP_LIST) {
+        OP *kid;
 	for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
 	    my_kid(kid, attrs, imopsp);
     } else if (type == OP_UNDEF) {
@@ -1821,6 +1836,7 @@ Perl_invert(pTHX_ OP *o)
 OP *
 Perl_scope(pTHX_ OP *o)
 {
+    dVAR;
     if (o) {
 	if (o->op_flags & OPf_PARENS || PERLDB_NOOPT || PL_tainting) {
 	    o = prepend_elem(OP_LINESEQ, newOP(OP_ENTER, 0), o);
@@ -1871,7 +1887,7 @@ Perl_block_start(pTHX_ int full)
 OP*
 Perl_block_end(pTHX_ I32 floor, OP *seq)
 {
-    int needblockscope = PL_hints & HINT_BLOCK_SCOPE;
+    const int needblockscope = PL_hints & HINT_BLOCK_SCOPE;
     OP* retval = scalarseq(seq);
     LEAVE_SCOPE(floor);
     PL_compiling.op_private = (U8)(PL_hints & HINT_PRIVATE_MASK);
@@ -1884,7 +1900,7 @@ Perl_block_end(pTHX_ I32 floor, OP *seq)
 STATIC OP *
 S_newDEFSVOP(pTHX)
 {
-    I32 offset = pad_findmy("$_");
+    const I32 offset = pad_findmy("$_");
     if (offset == NOT_IN_PAD || PAD_COMPNAME_FLAGS(offset) & SVpad_OUR) {
 	return newSVREF(newGVOP(OP_GV, 0, PL_defgv));
     }
@@ -2006,6 +2022,7 @@ Perl_jmaybe(pTHX_ OP *o)
 OP *
 Perl_fold_constants(pTHX_ register OP *o)
 {
+    dVAR;
     register OP *curop;
     I32 type = o->op_type;
     SV *sv;
@@ -2085,8 +2102,9 @@ Perl_fold_constants(pTHX_ register OP *o)
 OP *
 Perl_gen_constant_list(pTHX_ register OP *o)
 {
+    dVAR;
     register OP *curop;
-    I32 oldtmps_floor = PL_tmps_floor;
+    const I32 oldtmps_floor = PL_tmps_floor;
 
     list(o);
     if (PL_error_count)
@@ -2116,6 +2134,7 @@ Perl_gen_constant_list(pTHX_ register OP *o)
 OP *
 Perl_convert(pTHX_ I32 type, I32 flags, OP *o)
 {
+    dVAR;
     if (!o || o->op_type != OP_LIST)
 	o = newLISTOP(OP_LIST, 0, o, Nullop);
     else
@@ -2129,7 +2148,7 @@ Perl_convert(pTHX_ I32 type, I32 flags, OP *o)
     o->op_flags |= flags;
 
     o = CHECKOP(type, o);
-    if (o->op_type != type)
+    if (o->op_type != (unsigned)type)
 	return o;
 
     return fold_constants(o);
@@ -2146,7 +2165,7 @@ Perl_append_elem(pTHX_ I32 type, OP *first, OP *last)
     if (!last)
 	return first;
 
-    if (first->op_type != type
+    if (first->op_type != (unsigned)type
 	|| (type == OP_LIST && (first->op_flags & OPf_PARENS)))
     {
 	return newLISTOP(type, 0, first, last);
@@ -2171,10 +2190,10 @@ Perl_append_list(pTHX_ I32 type, LISTOP *first, LISTOP *last)
     if (!last)
 	return (OP*)first;
 
-    if (first->op_type != type)
+    if (first->op_type != (unsigned)type)
 	return prepend_elem(type, (OP*)first, (OP*)last);
 
-    if (last->op_type != type)
+    if (last->op_type != (unsigned)type)
 	return append_elem(type, (OP*)first, (OP*)last);
 
     first->op_last->op_sibling = last->op_first;
@@ -2195,7 +2214,7 @@ Perl_prepend_elem(pTHX_ I32 type, OP *first, OP *last)
     if (!last)
 	return first;
 
-    if (last->op_type == type) {
+    if (last->op_type == (unsigned)type) {
 	if (type == OP_LIST) {	/* already a PUSHMARK there */
 	    first->op_sibling = ((LISTOP*)last)->op_first->op_sibling;
 	    ((LISTOP*)last)->op_first->op_sibling = first;
@@ -2237,6 +2256,7 @@ Perl_force_list(pTHX_ OP *o)
 OP *
 Perl_newLISTOP(pTHX_ I32 type, I32 flags, OP *first, OP *last)
 {
+    dVAR;
     LISTOP *listop;
 
     NewOp(1101, listop, 1, LISTOP);
@@ -2271,6 +2291,7 @@ Perl_newLISTOP(pTHX_ I32 type, I32 flags, OP *first, OP *last)
 OP *
 Perl_newOP(pTHX_ I32 type, I32 flags)
 {
+    dVAR;
     OP *o;
     NewOp(1101, o, 1, OP);
     o->op_type = (OPCODE)type;
@@ -2289,6 +2310,7 @@ Perl_newOP(pTHX_ I32 type, I32 flags)
 OP *
 Perl_newUNOP(pTHX_ I32 type, I32 flags, OP *first)
 {
+    dVAR;
     UNOP *unop;
 
     if (!first)
@@ -2312,6 +2334,7 @@ Perl_newUNOP(pTHX_ I32 type, I32 flags, OP *first)
 OP *
 Perl_newBINOP(pTHX_ I32 type, I32 flags, OP *first, OP *last)
 {
+    dVAR;
     BINOP *binop;
     NewOp(1101, binop, 1, BINOP);
 
@@ -2340,8 +2363,8 @@ Perl_newBINOP(pTHX_ I32 type, I32 flags, OP *first, OP *last)
     return fold_constants((OP *)binop);
 }
 
-static int
-uvcompare(const void *a, const void *b)
+static int uvcompare(const void *a, const void *b) __attribute__nonnull__(1) __attribute__nonnull__(2) __attribute__pure__;
+static int uvcompare(const void *a, const void *b)
 {
     if (*((const UV *)a) < (*(const UV *)b))
 	return -1;
@@ -2361,8 +2384,8 @@ Perl_pmtrans(pTHX_ OP *o, OP *expr, OP *repl)
     SV *rstr = ((SVOP*)repl)->op_sv;
     STRLEN tlen;
     STRLEN rlen;
-    U8 *t = (U8*)SvPV(tstr, tlen);
-    U8 *r = (U8*)SvPV(rstr, rlen);
+    const U8 *t = (U8*)SvPV_const(tstr, tlen);
+    const U8 *r = (U8*)SvPV_const(rstr, rlen);
     register I32 i;
     register I32 j;
     I32 del;
@@ -2385,8 +2408,8 @@ Perl_pmtrans(pTHX_ OP *o, OP *expr, OP *repl)
     if (o->op_private & (OPpTRANS_FROM_UTF|OPpTRANS_TO_UTF)) {
 	SV* listsv = newSVpvn("# comment\n",10);
 	SV* transv = 0;
-	U8* tend = t + tlen;
-	U8* rend = r + rlen;
+	const U8* tend = t + tlen;
+	const U8* rend = r + rlen;
 	STRLEN ulen;
 	UV tfirst = 1;
 	UV tlast = 0;
@@ -2407,12 +2430,12 @@ Perl_pmtrans(pTHX_ OP *o, OP *expr, OP *repl)
 
 	if (!from_utf) {
 	    STRLEN len = tlen;
-	    tsave = t = bytes_to_utf8(t, &len);
+	    t = tsave = bytes_to_utf8(t, &len);
 	    tend = t + len;
 	}
 	if (!to_utf && rlen) {
 	    STRLEN len = rlen;
-	    rsave = r = bytes_to_utf8(r, &len);
+	    r = rsave = bytes_to_utf8(r, &len);
 	    rend = r + len;
 	}
 
@@ -2664,6 +2687,7 @@ Perl_pmtrans(pTHX_ OP *o, OP *expr, OP *repl)
 OP *
 Perl_newPMOP(pTHX_ I32 type, I32 flags)
 {
+    dVAR;
     PMOP *pmop;
 
     NewOp(1101, pmop, 1, PMOP);
@@ -2697,8 +2721,13 @@ Perl_newPMOP(pTHX_ I32 type, I32 flags)
 
         /* link into pm list */
     if (type != OP_TRANS && PL_curstash) {
-	pmop->op_pmnext = HvPMROOT(PL_curstash);
-	HvPMROOT(PL_curstash) = pmop;
+	MAGIC *mg = mg_find((SV*)PL_curstash, PERL_MAGIC_symtab);
+
+	if (!mg) {
+	    mg = sv_magicext((SV*)PL_curstash, 0, PERL_MAGIC_symtab, 0, 0, 0);
+	}
+	pmop->op_pmnext = (PMOP*)mg->mg_obj;
+	mg->mg_obj = (SV*)pmop;
 	PmopSTASH_set(pmop,PL_curstash);
     }
 
@@ -2720,6 +2749,7 @@ Perl_newPMOP(pTHX_ I32 type, I32 flags)
 OP *
 Perl_pmruntime(pTHX_ OP *o, OP *expr, bool isreg)
 {
+    dVAR;
     PMOP *pm;
     LOGOP *rcop;
     I32 repl_has_vars = 0;
@@ -2762,15 +2792,31 @@ Perl_pmruntime(pTHX_ OP *o, OP *expr, bool isreg)
     if (expr->op_type == OP_CONST) {
 	STRLEN plen;
 	SV *pat = ((SVOP*)expr)->op_sv;
-	char *p = SvPV(pat, plen);
+	const char *p = SvPV_const(pat, plen);
 	if ((o->op_flags & OPf_SPECIAL) && (*p == ' ' && p[1] == '\0')) {
+	    U32 was_readonly = SvREADONLY(pat);
+
+	    if (was_readonly) {
+		if (SvFAKE(pat)) {
+		    sv_force_normal_flags(pat, 0);
+		    assert(!SvREADONLY(pat));
+		    was_readonly = 0;
+		} else {
+		    SvREADONLY_off(pat);
+		}
+	    }   
+
 	    sv_setpvn(pat, "\\s+", 3);
-	    p = SvPV(pat, plen);
+
+	    SvFLAGS(pat) |= was_readonly;
+
+	    p = SvPV_const(pat, plen);
 	    pm->op_pmflags |= PMf_SKIPWHITE;
 	}
         if (DO_UTF8(pat))
 	    pm->op_pmdynflags |= PMdf_UTF8;
-	PM_SETRE(pm, CALLREGCOMP(aTHX_ p, p + plen, pm));
+	/* FIXME - can we make this function take const char * args?  */
+	PM_SETRE(pm, CALLREGCOMP(aTHX_ (char*)p, (char*)p + plen, pm));
 	if (strEQ("\\s+", PM_GETRE(pm)->precomp))
 	    pm->op_pmflags |= PMf_WHITE;
 	op_free(expr);
@@ -2889,6 +2935,7 @@ Perl_pmruntime(pTHX_ OP *o, OP *expr, bool isreg)
 OP *
 Perl_newSVOP(pTHX_ I32 type, I32 flags, SV *sv)
 {
+    dVAR;
     SVOP *svop;
     NewOp(1101, svop, 1, SVOP);
     svop->op_type = (OPCODE)type;
@@ -2906,6 +2953,7 @@ Perl_newSVOP(pTHX_ I32 type, I32 flags, SV *sv)
 OP *
 Perl_newPADOP(pTHX_ I32 type, I32 flags, SV *sv)
 {
+    dVAR;
     PADOP *padop;
     NewOp(1101, padop, 1, PADOP);
     padop->op_type = (OPCODE)type;
@@ -2927,6 +2975,7 @@ Perl_newPADOP(pTHX_ I32 type, I32 flags, SV *sv)
 OP *
 Perl_newGVOP(pTHX_ I32 type, I32 flags, GV *gv)
 {
+    dVAR;
 #ifdef USE_ITHREADS
     if (gv)
 	GvIN_PAD_on(gv);
@@ -2939,6 +2988,7 @@ Perl_newGVOP(pTHX_ I32 type, I32 flags, GV *gv)
 OP *
 Perl_newPVOP(pTHX_ I32 type, I32 flags, char *pv)
 {
+    dVAR;
     PVOP *pvop;
     NewOp(1101, pvop, 1, PVOP);
     pvop->op_type = (OPCODE)type;
@@ -2956,13 +3006,13 @@ Perl_newPVOP(pTHX_ I32 type, I32 flags, char *pv)
 void
 Perl_package(pTHX_ OP *o)
 {
-    char *name;
+    const char *name;
     STRLEN len;
 
     save_hptr(&PL_curstash);
     save_item(PL_curstname);
 
-    name = SvPV(cSVOPo->op_sv, len);
+    name = SvPV_const(cSVOPo->op_sv, len);
     PL_curstash = gv_stashpvn(name, len, TRUE);
     sv_setpvn(PL_curstname, name, len);
     op_free(o);
@@ -3004,7 +3054,11 @@ Perl_utilize(pTHX_ int aver, I32 floor, OP *version, OP *idop, OP *arg)
 	    meth = newSVpvn("VERSION",7);
 	    sv_upgrade(meth, SVt_PVIV);
 	    (void)SvIOK_on(meth);
-	    PERL_HASH(SvUVX(meth), SvPVX(meth), SvCUR(meth));
+	    {
+		U32 hash;
+		PERL_HASH(hash, SvPVX_const(meth), SvCUR(meth));
+		SvUV_set(meth, hash);
+	    }
 	    veop = convert(OP_ENTERSUB, OPf_STACKED|OPf_SPECIAL,
 			    append_elem(OP_LIST,
 					prepend_elem(OP_LIST, pack, list(version)),
@@ -3026,9 +3080,13 @@ Perl_utilize(pTHX_ int aver, I32 floor, OP *version, OP *idop, OP *arg)
 
 	/* Fake up a method call to import/unimport */
 	meth = aver ? newSVpvn("import",6) : newSVpvn("unimport", 8);
-	(void)SvUPGRADE(meth, SVt_PVIV);
+	SvUPGRADE(meth, SVt_PVIV);
 	(void)SvIOK_on(meth);
-	PERL_HASH(SvUVX(meth), SvPVX(meth), SvCUR(meth));
+	{
+	    U32 hash;
+	    PERL_HASH(hash, SvPVX_const(meth), SvCUR(meth));
+	    SvUV_set(meth, hash);
+	}
 	imop = convert(OP_ENTERSUB, OPf_STACKED|OPf_SPECIAL,
 		       append_elem(OP_LIST,
 				   prepend_elem(OP_LIST, pack, list(arg)),
@@ -3134,9 +3192,9 @@ Perl_vload_module(pTHX_ U32 flags, SV *name, SV *ver, va_list *args)
 	}
     }
     {
-	line_t ocopline = PL_copline;
-	COP *ocurcop = PL_curcop;
-	int oexpect = PL_expect;
+	const line_t ocopline = PL_copline;
+	COP * const ocurcop = PL_curcop;
+	const int oexpect = PL_expect;
 
 	utilize(!(flags & PERL_LOADMOD_DENY), start_subparse(FALSE, 0),
 		veop, modname, imop);
@@ -3178,7 +3236,7 @@ Perl_newSLICEOP(pTHX_ I32 flags, OP *subscript, OP *listval)
 }
 
 STATIC I32
-S_list_assignment(pTHX_ register OP *o)
+S_is_list_assignment(pTHX_ register const OP *o)
 {
     if (!o)
 	return TRUE;
@@ -3187,8 +3245,8 @@ S_list_assignment(pTHX_ register OP *o)
 	o = cUNOPo->op_first;
 
     if (o->op_type == OP_COND_EXPR) {
-	I32 t = list_assignment(cLOGOPo->op_first->op_sibling);
-	I32 f = list_assignment(cLOGOPo->op_first->op_sibling->op_sibling);
+        const I32 t = is_list_assignment(cLOGOPo->op_first->op_sibling);
+        const I32 f = is_list_assignment(cLOGOPo->op_first->op_sibling->op_sibling);
 
 	if (t && f)
 	    return TRUE;
@@ -3233,7 +3291,7 @@ Perl_newASSIGNOP(pTHX_ I32 flags, OP *left, I32 optype, OP *right)
 	}
     }
 
-    if (list_assignment(left)) {
+    if (is_list_assignment(left)) {
 	OP *curop;
 
 	PL_modcount = 0;
@@ -3282,7 +3340,7 @@ Perl_newASSIGNOP(pTHX_ I32 flags, OP *left, I32 optype, OP *right)
 			GV *gv = cGVOPx_gv(curop);
 			if (gv == PL_defgv || (int)SvCUR(gv) == PL_generation)
 			    break;
-			SvCUR(gv) = PL_generation;
+			SvCUR_set(gv, PL_generation);
 		    }
 		    else if (curop->op_type == OP_PADSV ||
 			     curop->op_type == OP_PADAV ||
@@ -3292,8 +3350,7 @@ Perl_newASSIGNOP(pTHX_ I32 flags, OP *left, I32 optype, OP *right)
 			if (PAD_COMPNAME_GEN(curop->op_targ)
 						    == (STRLEN)PL_generation)
 			    break;
-			PAD_COMPNAME_GEN(curop->op_targ)
-			    				= PL_generation;
+			PAD_COMPNAME_GEN_set(curop->op_targ, PL_generation);
 
 		    }
 		    else if (curop->op_type == OP_RV2CV)
@@ -3315,7 +3372,7 @@ Perl_newASSIGNOP(pTHX_ I32 flags, OP *left, I32 optype, OP *right)
 #endif
 			    if (gv == PL_defgv || (int)SvCUR(gv) == PL_generation)
 				break;
-			    SvCUR(gv) = PL_generation;
+			    SvCUR_set(gv, PL_generation);
 			}
 		    }
 		    else
@@ -3392,6 +3449,7 @@ Perl_newASSIGNOP(pTHX_ I32 flags, OP *left, I32 optype, OP *right)
 OP *
 Perl_newSTATEOP(pTHX_ I32 flags, char *label, OP *o)
 {
+    dVAR;
     const U32 seq = intro_my();
     register COP *cop;
 
@@ -3445,7 +3503,7 @@ Perl_newSTATEOP(pTHX_ I32 flags, char *label, OP *o)
 	SV **svp = av_fetch(CopFILEAV(PL_curcop), (I32)CopLINE(cop), FALSE);
         if (svp && *svp != &PL_sv_undef ) {
            (void)SvIOK_on(*svp);
-	    SvIVX(*svp) = PTR2IV(cop);
+	    SvIV_set(*svp, PTR2IV(cop));
 	}
     }
 
@@ -3456,12 +3514,14 @@ Perl_newSTATEOP(pTHX_ I32 flags, char *label, OP *o)
 OP *
 Perl_newLOGOP(pTHX_ I32 type, I32 flags, OP *first, OP *other)
 {
+    dVAR;
     return new_logop(type, flags, &first, &other);
 }
 
 STATIC OP *
 S_new_logop(pTHX_ I32 type, I32 flags, OP** firstp, OP** otherp)
 {
+    dVAR;
     LOGOP *logop;
     OP *o;
     OP *first = *firstp;
@@ -3502,7 +3562,7 @@ S_new_logop(pTHX_ I32 type, I32 flags, OP** firstp, OP** otherp)
 	}
 	else {
 	    /* check for C<my $x if 0>, or C<my($x,$y) if 0> */
-	    OP *o2 = other;
+	    const OP *o2 = other;
 	    if ( ! (o2->op_type == OP_LIST
 		    && (( o2 = cUNOPx(o2)->op_first))
 		    && o2->op_type == OP_PUSHMARK
@@ -3528,8 +3588,8 @@ S_new_logop(pTHX_ I32 type, I32 flags, OP** firstp, OP** otherp)
     else if (ckWARN(WARN_MISC) && (first->op_flags & OPf_KIDS) &&
              type != OP_DOR) /* [#24076] Don't warn for <FH> err FOO. */
     {
-	OP *k1 = ((UNOP*)first)->op_first;
-	OP *k2 = k1->op_sibling;
+	const OP *k1 = ((UNOP*)first)->op_first;
+	const OP *k2 = k1->op_sibling;
 	OPCODE warnop = 0;
 	switch (first->op_type)
 	{
@@ -3554,7 +3614,7 @@ S_new_logop(pTHX_ I32 type, I32 flags, OP** firstp, OP** otherp)
 	    break;
 	}
 	if (warnop) {
-	    line_t oldline = CopLINE(PL_curcop);
+	    const line_t oldline = CopLINE(PL_curcop);
 	    CopLINE_set(PL_curcop, PL_copline);
 	    Perl_warner(aTHX_ packWARN(WARN_MISC),
 		 "Value of %s%s can be \"0\"; test with defined()",
@@ -3596,6 +3656,7 @@ S_new_logop(pTHX_ I32 type, I32 flags, OP** firstp, OP** otherp)
 OP *
 Perl_newCONDOP(pTHX_ I32 flags, OP *first, OP *trueop, OP *falseop)
 {
+    dVAR;
     LOGOP *logop;
     OP *start;
     OP *o;
@@ -3651,6 +3712,7 @@ Perl_newCONDOP(pTHX_ I32 flags, OP *first, OP *trueop, OP *falseop)
 OP *
 Perl_newRANGE(pTHX_ I32 flags, OP *left, OP *right)
 {
+    dVAR;
     LOGOP *range;
     OP *flip;
     OP *flop;
@@ -3755,8 +3817,10 @@ Perl_newLOOPOP(pTHX_ I32 flags, I32 debuggable, OP *expr, OP *block)
 }
 
 OP *
-Perl_newWHILEOP(pTHX_ I32 flags, I32 debuggable, LOOP *loop, I32 whileline, OP *expr, OP *block, OP *cont)
+Perl_newWHILEOP(pTHX_ I32 flags, I32 debuggable, LOOP *loop, I32
+whileline, OP *expr, OP *block, OP *cont, I32 has_my)
 {
+    dVAR;
     OP *redo;
     OP *next = 0;
     OP *listop;
@@ -3791,7 +3855,7 @@ Perl_newWHILEOP(pTHX_ I32 flags, I32 debuggable, LOOP *loop, I32 whileline, OP *
 
     if (!block)
 	block = newOP(OP_NULL, 0);
-    else if (cont) {
+    else if (cont || has_my) {
 	block = scope(block);
     }
 
@@ -3851,6 +3915,7 @@ Perl_newWHILEOP(pTHX_ I32 flags, I32 debuggable, LOOP *loop, I32 whileline, OP *
 OP *
 Perl_newFOROP(pTHX_ I32 flags,char *label,line_t forline,OP *sv,OP *expr,OP *block,OP *cont)
 {
+    dVAR;
     LOOP *loop;
     OP *wop;
     PADOFFSET padoff = 0;
@@ -3943,7 +4008,7 @@ Perl_newFOROP(pTHX_ I32 flags,char *label,line_t forline,OP *sv,OP *expr,OP *blo
     Renew(loop, 1, LOOP);
 #endif
     loop->op_targ = padoff;
-    wop = newWHILEOP(flags, 1, loop, forline, newOP(OP_ITER, 0), block, cont);
+    wop = newWHILEOP(flags, 1, loop, forline, newOP(OP_ITER, 0), block, cont, 0);
     PL_copline = forline;
     return newSTATEOP(0, label, wop);
 }
@@ -3960,7 +4025,7 @@ Perl_newLOOPEX(pTHX_ I32 type, OP *label)
 	    o = newOP(type, OPf_SPECIAL);
 	else {
 	    o = newPVOP(type, 0, savepv(label->op_type == OP_CONST
-					? SvPVx(((SVOP*)label)->op_sv, n_a)
+					? SvPVx_const(((SVOP*)label)->op_sv, n_a)
 					: ""));
 	}
 	op_free(label);
@@ -3990,6 +4055,7 @@ children can still follow the full lexical scope chain.
 void
 Perl_cv_undef(pTHX_ CV *cv)
 {
+    dVAR;
 #ifdef USE_ITHREADS
     if (CvFILE(cv) && !CvXSUB(cv)) {
 	/* for XSUBs CvFILE point directly to static memory; __FILE__ */
@@ -4007,6 +4073,7 @@ Perl_cv_undef(pTHX_ CV *cv)
 
 	op_free(CvROOT(cv));
 	CvROOT(cv) = Nullop;
+	CvSTART(cv) = Nullop;
 	LEAVE;
     }
     SvPOK_off((SV*)cv);		/* forget prototype */
@@ -4034,7 +4101,7 @@ Perl_cv_undef(pTHX_ CV *cv)
 void
 Perl_cv_ckproto(pTHX_ const CV *cv, const GV *gv, const char *p)
 {
-    if (((!p != !SvPOK(cv)) || (p && strNE(p, SvPVX(cv)))) && ckWARN_d(WARN_PROTOTYPE)) {
+    if (((!p != !SvPOK(cv)) || (p && strNE(p, SvPVX_const(cv)))) && ckWARN_d(WARN_PROTOTYPE)) {
 	SV* msg = sv_newmortal();
 	SV* name = Nullsv;
 
@@ -4101,7 +4168,7 @@ Perl_cv_const_sv(pTHX_ CV *cv)
  */
 
 SV *
-Perl_op_const_sv(pTHX_ OP *o, CV *cv)
+Perl_op_const_sv(pTHX_ const OP *o, CV *cv)
 {
     SV *sv = Nullsv;
 
@@ -4180,19 +4247,20 @@ Perl_newSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *block)
 CV *
 Perl_newATTRSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *attrs, OP *block)
 {
+    dVAR;
     STRLEN n_a;
-    char *name;
-    char *aname;
+    const char *aname;
     GV *gv;
-    char *ps;
+    const char *ps;
+    STRLEN ps_len;
     register CV *cv=0;
     SV *const_sv;
 
-    name = o ? SvPVx(cSVOPo->op_sv, n_a) : Nullch;
+    const char * const name = o ? SvPVx_const(cSVOPo->op_sv, n_a) : Nullch;
 
     if (proto) {
 	assert(proto->op_type == OP_CONST);
-	ps = SvPVx(((SVOP*)proto)->op_sv, n_a);
+	ps = SvPVx_const(((SVOP*)proto)->op_sv, ps_len);
     }
     else
 	ps = Nullch;
@@ -4202,7 +4270,7 @@ Perl_newATTRSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *attrs, OP *block)
 	Perl_sv_setpvf(aTHX_ sv, "%s[%s:%"IVdf"]",
 		       PL_curstash ? "__ANON__" : "__ANON__::__ANON__",
 		       CopFILE(PL_curcop), (IV)CopLINE(PL_curcop));
-	aname = SvPVX(sv);
+	aname = SvPVX_const(sv);
     }
     else
 	aname = Nullch;
@@ -4232,7 +4300,7 @@ Perl_newATTRSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *attrs, OP *block)
 	    cv_ckproto((CV*)gv, NULL, ps);
 	}
 	if (ps)
-	    sv_setpv((SV*)gv, ps);
+	    sv_setpvn((SV*)gv, ps, ps_len);
 	else
 	    sv_setiv((SV*)gv, -1);
 	SvREFCNT_dec(PL_compcv);
@@ -4255,7 +4323,7 @@ Perl_newATTRSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *attrs, OP *block)
 	const_sv = op_const_sv(block, Nullcv);
 
     if (cv) {
-        bool exists = CvROOT(cv) || CvXSUB(cv);
+        const bool exists = CvROOT(cv) || CvXSUB(cv);
 
 #ifdef GV_UNIQUE_CHECK
         if (exists && GvUNIQUE(gv)) {
@@ -4288,7 +4356,7 @@ Perl_newATTRSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *attrs, OP *block)
 		    || (CvCONST(cv)
 			&& (!const_sv || sv_cmp(cv_const_sv(cv), const_sv))))
 		{
-		    line_t oldline = CopLINE(PL_curcop);
+		    const line_t oldline = CopLINE(PL_curcop);
 		    if (PL_copline != NOLINE)
 			CopLINE_set(PL_curcop, PL_copline);
 		    Perl_warner(aTHX_ packWARN(WARN_REDEFINE),
@@ -4305,7 +4373,7 @@ Perl_newATTRSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *attrs, OP *block)
 	(void)SvREFCNT_inc(const_sv);
 	if (cv) {
 	    assert(!CvROOT(cv) && !CvCONST(cv));
-	    sv_setpv((SV*)cv, "");  /* prototype is "" */
+	    sv_setpvn((SV*)cv, "", 0);  /* prototype is "" */
 	    CvXSUBANY(cv).any_ptr = const_sv;
 	    CvXSUB(cv) = const_sv_xsub;
 	    CvCONST_on(cv);
@@ -4385,13 +4453,13 @@ Perl_newATTRSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *attrs, OP *block)
     CvSTASH(cv) = PL_curstash;
 
     if (ps)
-	sv_setpv((SV*)cv, ps);
+	sv_setpvn((SV*)cv, ps, ps_len);
 
     if (PL_error_count) {
 	op_free(block);
 	block = Nullop;
 	if (name) {
-	    char *s = strrchr(name, ':');
+	    const char *s = strrchr(name, ':');
 	    s = s ? s+1 : name;
 	    if (strEQ(s, "BEGIN")) {
 		const char not_safe[] =
@@ -4438,8 +4506,8 @@ Perl_newATTRSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *attrs, OP *block)
     }
 
     if (name || aname) {
-	char *s;
-	char *tname = (name ? name : aname);
+	const char *s;
+	const char *tname = (name ? name : aname);
 
 	if (PERLDB_SUBLINE && PL_curstash != PL_debstash) {
 	    SV *sv = NEWSV(0,0);
@@ -4452,9 +4520,9 @@ Perl_newATTRSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *attrs, OP *block)
 			   CopFILE(PL_curcop),
 			   (long)PL_subline, (long)CopLINE(PL_curcop));
 	    gv_efullname3(tmpstr, gv, Nullch);
-	    hv_store(GvHV(PL_DBsub), SvPVX(tmpstr), SvCUR(tmpstr), sv, 0);
+	    hv_store(GvHV(PL_DBsub), SvPVX_const(tmpstr), SvCUR(tmpstr), sv, 0);
 	    hv = GvHVn(db_postponed);
-	    if (HvFILL(hv) > 0 && hv_exists(hv, SvPVX(tmpstr), SvCUR(tmpstr))
+	    if (HvFILL(hv) > 0 && hv_exists(hv, SvPVX_const(tmpstr), SvCUR(tmpstr))
 		&& (pcv = GvCV(db_postponed)))
 	    {
 		dSP;
@@ -4474,7 +4542,7 @@ Perl_newATTRSUB(pTHX_ I32 floor, OP *o, OP *proto, OP *attrs, OP *block)
 	    goto done;
 
 	if (strEQ(s, "BEGIN") && !PL_error_count) {
-	    I32 oldscope = PL_scopestack_ix;
+	    const I32 oldscope = PL_scopestack_ix;
 	    ENTER;
 	    SAVECOPFILE(&PL_compiling);
 	    SAVECOPLINE(&PL_compiling);
@@ -4538,6 +4606,7 @@ eligible for inlining at compile-time.
 CV *
 Perl_newCONSTSUB(pTHX_ HV *stash, const char *name, SV *sv)
 {
+    dVAR;
     CV* cv;
 
     ENTER;
@@ -4558,7 +4627,7 @@ Perl_newCONSTSUB(pTHX_ HV *stash, const char *name, SV *sv)
     cv = newXS(name, const_sv_xsub, savepv(CopFILE(PL_curcop)));
     CvXSUBANY(cv).any_ptr = sv;
     CvCONST_on(cv);
-    sv_setpv((SV*)cv, "");  /* prototype is "" */
+    sv_setpvn((SV*)cv, "", 0);  /* prototype is "" */
 
     if (stash)
 	CopSTASH_free(PL_curcop);
@@ -4595,9 +4664,10 @@ Perl_newXS(pTHX_ const char *name, XSUBADDR_t subaddr, const char *filename)
 	}
 	else if (CvROOT(cv) || CvXSUB(cv) || GvASSUMECV(gv)) {
 	    /* already defined (or promised) */
+	    /* XXX It's possible for this HvNAME_get to return null, and get passed into strEQ */
 	    if (ckWARN(WARN_REDEFINE) && !(CvGV(cv) && GvSTASH(CvGV(cv))
-			    && strEQ(HvNAME(GvSTASH(CvGV(cv))), "autouse"))) {
-		line_t oldline = CopLINE(PL_curcop);
+			    && strEQ(HvNAME_get(GvSTASH(CvGV(cv))), "autouse"))) {
+		const line_t oldline = CopLINE(PL_curcop);
 		if (PL_copline != NOLINE)
 		    CopLINE_set(PL_curcop, PL_copline);
 		Perl_warner(aTHX_ packWARN(WARN_REDEFINE),
@@ -4695,7 +4765,7 @@ Perl_newFORM(pTHX_ I32 floor, OP *o, OP *block)
     GvMULTI_on(gv);
     if ((cv = GvFORM(gv))) {
 	if (ckWARN(WARN_REDEFINE)) {
-	    line_t oldline = CopLINE(PL_curcop);
+	    const line_t oldline = CopLINE(PL_curcop);
 	    if (PL_copline != NOLINE)
 		CopLINE_set(PL_curcop, PL_copline);
 	    Perl_warner(aTHX_ packWARN(WARN_REDEFINE),
@@ -4754,6 +4824,7 @@ Perl_newANONATTRSUB(pTHX_ I32 floor, OP *proto, OP *attrs, OP *block)
 OP *
 Perl_oopsAV(pTHX_ OP *o)
 {
+    dVAR;
     switch (o->op_type) {
     case OP_PADSV:
 	o->op_type = OP_PADAV;
@@ -4777,6 +4848,7 @@ Perl_oopsAV(pTHX_ OP *o)
 OP *
 Perl_oopsHV(pTHX_ OP *o)
 {
+    dVAR;
     switch (o->op_type) {
     case OP_PADSV:
     case OP_PADAV:
@@ -4802,6 +4874,7 @@ Perl_oopsHV(pTHX_ OP *o)
 OP *
 Perl_newAVREF(pTHX_ OP *o)
 {
+    dVAR;
     if (o->op_type == OP_PADANY) {
 	o->op_type = OP_PADAV;
 	o->op_ppaddr = PL_ppaddr[OP_PADAV];
@@ -4826,6 +4899,7 @@ Perl_newGVREF(pTHX_ I32 type, OP *o)
 OP *
 Perl_newHVREF(pTHX_ OP *o)
 {
+    dVAR;
     if (o->op_type == OP_PADANY) {
 	o->op_type = OP_PADHV;
 	o->op_ppaddr = PL_ppaddr[OP_PADHV];
@@ -4845,11 +4919,7 @@ Perl_oopsCV(pTHX_ OP *o)
     Perl_croak(aTHX_ "NOT IMPL LINE %d",__LINE__);
     /* STUB */
     (void)o;
-#ifndef HASATTRIBUTE
-    /* No __attribute__, so the compiler doesn't know that croak never returns
-     */
-    return 0;
-#endif
+    NORETURN_FUNCTION_END;
 }
 
 OP *
@@ -4861,6 +4931,7 @@ Perl_newCVREF(pTHX_ I32 flags, OP *o)
 OP *
 Perl_newSVREF(pTHX_ OP *o)
 {
+    dVAR;
     if (o->op_type == OP_PADANY) {
 	o->op_type = OP_PADSV;
 	o->op_ppaddr = PL_ppaddr[OP_PADSV];
@@ -4901,8 +4972,8 @@ Perl_ck_bitop(pTHX_ OP *o)
 	     || o->op_type == OP_BIT_AND
 	     || o->op_type == OP_BIT_XOR))
     {
-	OP * left = cBINOPo->op_first;
-	OP * right = left->op_sibling;
+	const OP * const left = cBINOPo->op_first;
+	const OP * const right = left->op_sibling;
 	if ((OP_IS_NUMCOMPARE(left->op_type) &&
 		(left->op_flags & OPf_PARENS) == 0) ||
 	    (OP_IS_NUMCOMPARE(right->op_type) &&
@@ -4920,7 +4991,7 @@ Perl_ck_bitop(pTHX_ OP *o)
 OP *
 Perl_ck_concat(pTHX_ OP *o)
 {
-    OP *kid = cUNOPo->op_first;
+    const OP *kid = cUNOPo->op_first;
     if (kid->op_type == OP_CONCAT && !(kid->op_private & OPpTARGET_MY) &&
 	    !(kUNOP->op_first->op_flags & OPf_MOD))
         o->op_flags |= OPf_STACKED;
@@ -4930,10 +5001,11 @@ Perl_ck_concat(pTHX_ OP *o)
 OP *
 Perl_ck_spair(pTHX_ OP *o)
 {
+    dVAR;
     if (o->op_flags & OPf_KIDS) {
 	OP* newop;
 	OP* kid;
-	OPCODE type = o->op_type;
+	const OPCODE type = o->op_type;
 	o = modkids(ck_fun(o), type);
 	kid = cUNOPo->op_first;
 	newop = kUNOP->op_first->op_sibling;
@@ -4992,7 +5064,7 @@ Perl_ck_die(pTHX_ OP *o)
 OP *
 Perl_ck_eof(pTHX_ OP *o)
 {
-    I32 type = o->op_type;
+    const I32 type = o->op_type;
 
     if (o->op_flags & OPf_KIDS) {
 	if (cLISTOPo->op_first->op_type == OP_STUB) {
@@ -5007,6 +5079,7 @@ Perl_ck_eof(pTHX_ OP *o)
 OP *
 Perl_ck_eval(pTHX_ OP *o)
 {
+    dVAR;
     PL_hints |= HINT_BLOCK_SCOPE;
     if (o->op_flags & OPf_KIDS) {
 	SVOP *kid = (SVOP*)cUNOPo->op_first;
@@ -5066,8 +5139,8 @@ Perl_ck_exit(pTHX_ OP *o)
 OP *
 Perl_ck_exec(pTHX_ OP *o)
 {
-    OP *kid;
     if (o->op_flags & OPf_STACKED) {
+        OP *kid;
 	o = ck_fun(o);
 	kid = cUNOPo->op_first->op_sibling;
 	if (kid->op_type == OP_RV2GV)
@@ -5101,32 +5174,22 @@ Perl_ck_exists(pTHX_ OP *o)
     return o;
 }
 
-#if 0
-OP *
-Perl_ck_gvconst(pTHX_ register OP *o)
-{
-    o = fold_constants(o);
-    if (o->op_type == OP_CONST)
-	o->op_type = OP_GV;
-    return o;
-}
-#endif
-
 OP *
 Perl_ck_rvconst(pTHX_ register OP *o)
 {
+    dVAR;
     SVOP *kid = (SVOP*)cUNOPo->op_first;
 
     o->op_private |= (PL_hints & HINT_STRICT_REFS);
     if (kid->op_type == OP_CONST) {
 	int iscv;
 	GV *gv;
-	SV *kidsv = kid->op_sv;
+	SV * const kidsv = kid->op_sv;
 
 	/* Is it a constant from cv_const_sv()? */
 	if (SvROK(kidsv) && SvREADONLY(kidsv)) {
 	    SV *rsv = SvRV(kidsv);
-	    int svtype = SvTYPE(rsv);
+	    const int svtype = SvTYPE(rsv);
             const char *badtype = Nullch;
 
 	    switch (o->op_type) {
@@ -5213,7 +5276,8 @@ Perl_ck_rvconst(pTHX_ register OP *o)
 OP *
 Perl_ck_ftst(pTHX_ OP *o)
 {
-    I32 type = o->op_type;
+    dVAR;
+    const I32 type = o->op_type;
 
     if (o->op_flags & OPf_REF) {
 	/* nothing */
@@ -5250,11 +5314,7 @@ Perl_ck_ftst(pTHX_ OP *o)
 OP *
 Perl_ck_fun(pTHX_ OP *o)
 {
-    register OP *kid;
-    OP **tokid;
-    OP *sibl;
-    I32 numargs = 0;
-    int type = o->op_type;
+    const int type = o->op_type;
     register I32 oa = PL_opargs[type] >> OASHIFT;
 
     if (o->op_flags & OPf_STACKED) {
@@ -5265,8 +5325,11 @@ Perl_ck_fun(pTHX_ OP *o)
     }
 
     if (o->op_flags & OPf_KIDS) {
-	tokid = &cLISTOPo->op_first;
-	kid = cLISTOPo->op_first;
+        OP **tokid = &cLISTOPo->op_first;
+        register OP *kid = cLISTOPo->op_first;
+        OP *sibl;
+        I32 numargs = 0;
+
 	if (kid->op_type == OP_PUSHMARK ||
 	    (kid->op_type == OP_NULL && kid->op_targ == OP_PUSHMARK))
 	{
@@ -5428,7 +5491,7 @@ Perl_ck_fun(pTHX_ OP *o)
 				      else if (op->op_type == OP_PADAV
 					       || op->op_type == OP_PADHV) {
 					   /* lexicalvar $a[] or $h{} */
-					   char *padname =
+					   const char *padname =
 						PAD_COMPNAME_PV(op->op_targ);
 					   if (padname)
 						tmpstr =
@@ -5453,7 +5516,7 @@ Perl_ck_fun(pTHX_ OP *o)
 				SV *namesv;
 				targ = pad_alloc(OP_RV2GV, SVs_PADTMP);
 				namesv = PAD_SVl(targ);
-				(void)SvUPGRADE(namesv, SVt_PV);
+				SvUPGRADE(namesv, SVt_PV);
 				if (*name != '$')
 				    sv_setpvn(namesv, "$", 1);
 				sv_catpvn(namesv, name, len);
@@ -5499,6 +5562,7 @@ Perl_ck_fun(pTHX_ OP *o)
 OP *
 Perl_ck_glob(pTHX_ OP *o)
 {
+    dVAR;
     GV *gv;
 
     o = ck_fun(o);
@@ -5553,9 +5617,10 @@ Perl_ck_glob(pTHX_ OP *o)
 OP *
 Perl_ck_grep(pTHX_ OP *o)
 {
+    dVAR;
     LOGOP *gwop;
     OP *kid;
-    OPCODE type = o->op_type == OP_GREPSTART ? OP_GREPWHILE : OP_MAPWHILE;
+    const OPCODE type = o->op_type == OP_GREPSTART ? OP_GREPWHILE : OP_MAPWHILE;
     I32 offset;
 
     o->op_ppaddr = PL_ppaddr[OP_GREPSTART];
@@ -5565,6 +5630,8 @@ Perl_ck_grep(pTHX_ OP *o)
 	OP* k;
 	o = ck_sort(o);
         kid = cLISTOPo->op_first->op_sibling;
+	if (!cUNOPx(kid)->op_next)
+	    Perl_croak(aTHX_ "panic: ck_grep");
 	for (k = cUNOPx(kid)->op_first; k; k = k->op_next) {
 	    kid = k;
 	}
@@ -5632,7 +5699,7 @@ Perl_ck_lengthconst(pTHX_ OP *o)
 OP *
 Perl_ck_lfun(pTHX_ OP *o)
 {
-    OPCODE type = o->op_type;
+    const OPCODE type = o->op_type;
     return modkids(ck_fun(o), type);
 }
 
@@ -5677,7 +5744,7 @@ Perl_ck_defined(pTHX_ OP *o)		/* 19990527 MJD */
 OP *
 Perl_ck_rfun(pTHX_ OP *o)
 {
-    OPCODE type = o->op_type;
+    const OPCODE type = o->op_type;
     return refkids(ck_fun(o), type);
 }
 
@@ -5758,7 +5825,7 @@ OP *
 Perl_ck_match(pTHX_ OP *o)
 {
     if (o->op_type != OP_QR) {
-	I32 offset = pad_findmy("$_");
+	const I32 offset = pad_findmy("$_");
 	if (offset != NOT_IN_PAD && !(PAD_COMPNAME_FLAGS(offset) & SVpad_OUR)) {
 	    o->op_targ = offset;
 	    o->op_private |= OPpTARGET_MY;
@@ -5775,10 +5842,10 @@ Perl_ck_method(pTHX_ OP *o)
     OP *kid = cUNOPo->op_first;
     if (kid->op_type == OP_CONST) {
 	SV* sv = kSVOP->op_sv;
-	if (!(strchr(SvPVX(sv), ':') || strchr(SvPVX(sv), '\''))) {
+	if (!(strchr(SvPVX_const(sv), ':') || strchr(SvPVX_const(sv), '\''))) {
 	    OP *cmop;
 	    if (!SvREADONLY(sv) || !SvFAKE(sv)) {
-		sv = newSVpvn_share(SvPVX(sv), SvCUR(sv), 0);
+		sv = newSVpvn_share(SvPVX_const(sv), SvCUR(sv), 0);
 	    }
 	    else {
 		kSVOP->op_sv = Nullsv;
@@ -5830,7 +5897,7 @@ Perl_ck_open(pTHX_ OP *o)
 	 OP *first = cLISTOPx(o)->op_first; /* The pushmark. */
 	 OP *last  = cLISTOPx(o)->op_last;  /* The bareword. */
 	 OP *oa;
-	 char *mode;
+	 const char *mode;
 
 	 if ((last->op_type == OP_CONST) &&		/* The bareword. */
 	     (last->op_private & OPpCONST_BARE) &&
@@ -5838,7 +5905,7 @@ Perl_ck_open(pTHX_ OP *o)
 	     (oa = first->op_sibling) &&		/* The fh. */
 	     (oa = oa->op_sibling) &&			/* The mode. */
 	     SvPOK(((SVOP*)oa)->op_sv) &&
-	     (mode = SvPVX(((SVOP*)oa)->op_sv)) &&
+	     (mode = SvPVX_const(((SVOP*)oa)->op_sv)) &&
 	     mode[0] == '>' && mode[1] == '&' &&	/* A dup open. */
 	     (last == oa->op_sibling))			/* The bareword. */
 	      last->op_private &= ~OPpCONST_STRICT;
@@ -5867,21 +5934,29 @@ Perl_ck_require(pTHX_ OP *o)
 	SVOP *kid = (SVOP*)cUNOPo->op_first;
 
 	if (kid->op_type == OP_CONST && (kid->op_private & OPpCONST_BARE)) {
+	    SV *sv = kid->op_sv;
+	    U32 was_readonly = SvREADONLY(sv);
 	    char *s;
-	    for (s = SvPVX(kid->op_sv); *s; s++) {
+
+	    if (was_readonly) {
+		if (SvFAKE(sv)) {
+		    sv_force_normal_flags(sv, 0);
+		    assert(!SvREADONLY(sv));
+		    was_readonly = 0;
+		} else {
+		    SvREADONLY_off(sv);
+		}
+	    }   
+
+	    for (s = SvPVX(sv); *s; s++) {
 		if (*s == ':' && s[1] == ':') {
 		    *s = '/';
 		    Move(s+2, s+1, strlen(s+2)+1, char);
-		    --SvCUR(kid->op_sv);
+		    SvCUR_set(sv, SvCUR(sv) - 1);
 		}
 	    }
-	    if (SvREADONLY(kid->op_sv)) {
-		SvREADONLY_off(kid->op_sv);
-		sv_catpvn(kid->op_sv, ".pm", 3);
-		SvREADONLY_on(kid->op_sv);
-	    }
-	    else
-		sv_catpvn(kid->op_sv, ".pm", 3);
+	    sv_catpvn(sv, ".pm", 3);
+	    SvFLAGS(sv) |= was_readonly;
 	}
     }
 
@@ -5907,8 +5982,8 @@ Perl_ck_require(pTHX_ OP *o)
 OP *
 Perl_ck_return(pTHX_ OP *o)
 {
-    OP *kid;
     if (CvLVALUE(PL_compcv)) {
+        OP *kid;
 	for (kid = cLISTOPo->op_first->op_sibling; kid; kid = kid->op_sibling)
 	    mod(kid, OP_LEAVESUBLV);
     }
@@ -5928,6 +6003,7 @@ Perl_ck_retarget(pTHX_ OP *o)
 OP *
 Perl_ck_select(pTHX_ OP *o)
 {
+    dVAR;
     OP* kid;
     if (o->op_flags & OPf_KIDS) {
 	kid = cLISTOPo->op_first->op_sibling;	/* get past pushmark */
@@ -5948,7 +6024,7 @@ Perl_ck_select(pTHX_ OP *o)
 OP *
 Perl_ck_shift(pTHX_ OP *o)
 {
-    I32 type = o->op_type;
+    const I32 type = o->op_type;
 
     if (!(o->op_flags & OPf_KIDS)) {
 	OP *argop;
@@ -6096,6 +6172,7 @@ S_simplify_sort(pTHX_ OP *o)
 OP *
 Perl_ck_split(pTHX_ OP *o)
 {
+    dVAR;
     register OP *kid;
 
     if (o->op_flags & OPf_STACKED)
@@ -6152,11 +6229,10 @@ OP *
 Perl_ck_join(pTHX_ OP *o)
 {
     if (ckWARN(WARN_SYNTAX)) {
-	OP *kid = cLISTOPo->op_first->op_sibling;
+	const OP *kid = cLISTOPo->op_first->op_sibling;
 	if (kid && kid->op_type == OP_MATCH) {
-	    const char *pmstr = "STRING";
-	    if (PM_GETRE(kPMOP))
-		pmstr = PM_GETRE(kPMOP)->precomp;
+            const REGEXP *re = PM_GETRE(kPMOP);
+	    const char *pmstr = re ? re->precomp : "STRING";
 	    Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
 			"/%s/ should probably be written as \"%s\"",
 			pmstr, pmstr);
@@ -6180,7 +6256,7 @@ Perl_ck_subr(pTHX_ OP *o)
     I32 contextclass = 0;
     char *e = 0;
     STRLEN n_a;
-    bool delete=0;
+    bool delete_op = 0;
 
     o->op_private |= OPpENTERSUB_HASTARG;
     for (cvop = o2; cvop->op_sibling; cvop = cvop->op_sibling) ;
@@ -6205,7 +6281,7 @@ Perl_ck_subr(pTHX_ OP *o)
 			    o->op_private |= OPpENTERSUB_DB;
 		    }
 		    else {
-			delete=1;
+			delete_op = 1;
 			if (ckWARN(WARN_ASSERTIONS) && !(PL_hints & HINT_ASSERTIONSSEEN)) {
 			    Perl_warner(aTHX_ packWARN(WARN_ASSERTIONS),
 					"Impossible to activate assertion call");
@@ -6309,8 +6385,8 @@ Perl_ck_subr(pTHX_ OP *o)
 		     break;
 		case ']':
 		     if (contextclass) {
-			 char *p = proto;
-			 char s = *p;
+		         char *p = proto;
+			 const char s = *p;
 			 contextclass = 0;
 			 *p = '\0';
 			 while (*--p != '[');
@@ -6393,7 +6469,7 @@ Perl_ck_subr(pTHX_ OP *o)
     if (proto && !optional &&
 	  (*proto && *proto != '@' && *proto != '%' && *proto != ';'))
 	return too_few_arguments(o, gv_ename(namegv));
-    if(delete) {
+    if(delete_op) {
 	op_free(o);
 	o=newSVOP(OP_CONST, 0, newSViv(0));
     }
@@ -6460,6 +6536,7 @@ Perl_ck_substr(pTHX_ OP *o)
 void
 Perl_peep(pTHX_ register OP *o)
 {
+    dVAR;
     register OP* oldop = 0;
 
     if (!o || o->op_opt)
@@ -6488,7 +6565,7 @@ Perl_peep(pTHX_ register OP *o)
 	     * Despite being a "constant", the SV is written to,
 	     * for reference counts, sv_upgrade() etc. */
 	    if (cSVOP->op_sv) {
-		PADOFFSET ix = pad_alloc(OP_CONST, SVs_PADTMP);
+		const PADOFFSET ix = pad_alloc(OP_CONST, SVs_PADTMP);
 		if (o->op_type == OP_CONST && SvPADTMP(cSVOPo->op_sv)) {
 		    /* If op_sv is already a PADTMP then it is being used by
 		     * some pad, so make a copy. */
@@ -6611,7 +6688,7 @@ Perl_peep(pTHX_ register OP *o)
 	    }
 	    else if ((o->op_private & OPpEARLY_CV) && ckWARN(WARN_PROTOTYPE)) {
 		GV *gv = cGVOPo_gv;
-		if (SvTYPE(gv) == SVt_PVGV && GvCV(gv) && SvPVX(GvCV(gv))) {
+		if (SvTYPE(gv) == SVt_PVGV && GvCV(gv) && SvPVX_const(GvCV(gv))) {
 		    /* XXX could check prototype here instead of just carping */
 		    SV *sv = sv_newmortal();
 		    gv_efullname3(sv, gv, Nullch);
@@ -6683,7 +6760,7 @@ Perl_peep(pTHX_ register OP *o)
 			o->op_next->op_sibling->op_type != OP_EXIT &&
 			o->op_next->op_sibling->op_type != OP_WARN &&
 			o->op_next->op_sibling->op_type != OP_DIE) {
-		    line_t oldline = CopLINE(PL_curcop);
+		    const line_t oldline = CopLINE(PL_curcop);
 
 		    CopLINE_set(PL_curcop, CopLINE((COP*)o->op_next));
 		    Perl_warner(aTHX_ packWARN(WARN_EXEC),
@@ -6737,7 +6814,7 @@ Perl_peep(pTHX_ register OP *o)
 	    {
 		Perl_croak(aTHX_ "No such class field \"%s\" " 
 			   "in variable %s of type %s", 
-		      key, SvPV_nolen(lexname), HvNAME(SvSTASH(lexname)));
+		      key, SvPV_nolen(lexname), HvNAME_get(SvSTASH(lexname)));
 	    }
 
             break;
@@ -6794,7 +6871,7 @@ Perl_peep(pTHX_ register OP *o)
 		{
 		    Perl_croak(aTHX_ "No such class field \"%s\" "
 			       "in variable %s of type %s",
-			  key, SvPV_nolen(lexname), HvNAME(SvSTASH(lexname)));
+			  key, SvPV_nolen(lexname), HvNAME_get(SvSTASH(lexname)));
 		}
 	    }
 	    break;
@@ -7026,13 +7103,13 @@ Perl_custom_op_name(pTHX_ const OP* o)
     HE* he;
 
     if (!PL_custom_op_names) /* This probably shouldn't happen */
-        return PL_op_name[OP_CUSTOM];
+        return (char *)PL_op_name[OP_CUSTOM];
 
     keysv = sv_2mortal(newSViv(index));
 
     he = hv_fetch_ent(PL_custom_op_names, keysv, 0, 0);
     if (!he)
-        return PL_op_name[OP_CUSTOM]; /* Don't know who you are */
+        return (char *)PL_op_name[OP_CUSTOM]; /* Don't know who you are */
 
     return SvPV_nolen(HeVAL(he));
 }
@@ -7045,13 +7122,13 @@ Perl_custom_op_desc(pTHX_ const OP* o)
     HE* he;
 
     if (!PL_custom_op_descs)
-        return PL_op_desc[OP_CUSTOM];
+        return (char *)PL_op_desc[OP_CUSTOM];
 
     keysv = sv_2mortal(newSViv(index));
 
     he = hv_fetch_ent(PL_custom_op_descs, keysv, 0, 0);
     if (!he)
-        return PL_op_desc[OP_CUSTOM];
+        return (char *)PL_op_desc[OP_CUSTOM];
 
     return SvPV_nolen(HeVAL(he));
 }
@@ -7066,10 +7143,20 @@ const_sv_xsub(pTHX_ CV* cv)
     if (items != 0) {
 #if 0
         Perl_croak(aTHX_ "usage: %s::%s()",
-                   HvNAME(GvSTASH(CvGV(cv))), GvNAME(CvGV(cv)));
+                   HvNAME_get(GvSTASH(CvGV(cv))), GvNAME(CvGV(cv)));
 #endif
     }
     EXTEND(sp, 1);
     ST(0) = (SV*)XSANY.any_ptr;
     XSRETURN(1);
 }
+
+/*
+ * Local variables:
+ * c-indentation-style: bsd
+ * c-basic-offset: 4
+ * indent-tabs-mode: t
+ * End:
+ *
+ * ex: set ts=8 sts=4 sw=4 noet:
+ */