This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
Merge branch 'blead' into dual/Safe
[perl5.git] / pp_ctl.c
index 2419f27..0eb513f 100644 (file)
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -1,7 +1,7 @@
 /*    pp_ctl.c
  *
- *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- *    2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 by Larry Wall and others
+ *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
+ *    2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
  *
  *    You may distribute under the terms of either the GNU General Public
  *    License or the Artistic License, as specified in the README file.
@@ -9,12 +9,14 @@
  */
 
 /*
- * Now far ahead the Road has gone,
- * And I must follow, if I can,
- * Pursuing it with eager feet,
- * Until it joins some larger way
- * Where many paths and errands meet.
- * And whither then?  I cannot say.
+ *      Now far ahead the Road has gone,
+ *          And I must follow, if I can,
+ *      Pursuing it with eager feet,
+ *          Until it joins some larger way
+ *      Where many paths and errands meet.
+ *          And whither then?  I cannot say.
+ *
+ *     [Bilbo on p.35 of _The Lord of the Rings_, I/i: "A Long-Expected Party"]
  */
 
 /* This file contains control-oriented pp ("push/pop") functions that
@@ -95,7 +97,7 @@ PP(pp_regcomp)
        /* multiple args; concatentate them */
        dMARK; dORIGMARK;
        tmpstr = PAD_SV(ARGTARG);
-       sv_setpvn(tmpstr, "", 0);
+       sv_setpvs(tmpstr, "");
        while (++MARK <= SP) {
            if (PL_amagic_generation) {
                SV *sv;
@@ -231,7 +233,6 @@ PP(pp_substcont)
        if (!(cx->sb_rxtainted & 2) && SvTAINTED(TOPs))
            cx->sb_rxtainted |= 2;
        sv_catsv(dstr, POPs);
-       FREETMPS; /* Prevent excess tmp stack */
 
        /* Are we done */
        if (CxONCE(cx) || !CALLREGEXEC(rx, s, cx->sb_strend, orig,
@@ -298,7 +299,6 @@ PP(pp_substcont)
     { /* Update the pos() information. */
        SV * const sv = cx->sb_targ;
        MAGIC *mg;
-       I32 i;
        SvUPGRADE(sv, SVt_PVMG);
        if (!(mg = mg_find(sv, PERL_MAGIC_regex_global))) {
 #ifdef PERL_OLD_COPY_ON_WRITE
@@ -308,10 +308,7 @@ PP(pp_substcont)
            mg = sv_magicext(sv, NULL, PERL_MAGIC_regex_global, &PL_vtbl_mglob,
                             NULL, 0);
        }
-       i = m - orig;
-       if (DO_UTF8(sv))
-           sv_pos_b2u(sv, &i);
-       mg->mg_len = i;
+       mg->mg_len = m - orig;
     }
     if (old != rx)
        (void)ReREFCNT_inc(rx);
@@ -325,6 +322,8 @@ Perl_rxres_save(pTHX_ void **rsp, REGEXP *rx)
 {
     UV *p = (UV*)*rsp;
     U32 i;
+
+    PERL_ARGS_ASSERT_RXRES_SAVE;
     PERL_UNUSED_CONTEXT;
 
     if (!p || p[1] < RX_NPARENS(rx)) {
@@ -358,11 +357,13 @@ Perl_rxres_save(pTHX_ void **rsp, REGEXP *rx)
     }
 }
 
-void
-Perl_rxres_restore(pTHX_ void **rsp, REGEXP *rx)
+static void
+S_rxres_restore(pTHX_ void **rsp, REGEXP *rx)
 {
     UV *p = (UV*)*rsp;
     U32 i;
+
+    PERL_ARGS_ASSERT_RXRES_RESTORE;
     PERL_UNUSED_CONTEXT;
 
     RX_MATCH_COPY_FREE(rx);
@@ -386,10 +387,12 @@ Perl_rxres_restore(pTHX_ void **rsp, REGEXP *rx)
     }
 }
 
-void
-Perl_rxres_free(pTHX_ void **rsp)
+static void
+S_rxres_free(pTHX_ void **rsp)
 {
     UV * const p = (UV*)*rsp;
+
+    PERL_ARGS_ASSERT_RXRES_FREE;
     PERL_UNUSED_CONTEXT;
 
     if (p) {
@@ -437,7 +440,6 @@ PP(pp_formline)
     SV * nsv = NULL;
     OP * parseres = NULL;
     const char *fmt;
-    bool oneline;
 
     if (!SvMAGICAL(tmpForm) || !SvCOMPILED(tmpForm)) {
        if (SvREADONLY(tmpForm)) {
@@ -503,13 +505,13 @@ PP(pp_formline)
                *t = '\0';
                sv_catpvn_utf8_upgrade(PL_formtarget, f, arg, nsv);
                t = SvEND(PL_formtarget);
+               f += arg;
                break;
            }
            if (!targ_is_utf8 && DO_UTF8(tmpForm)) {
                SvCUR_set(PL_formtarget, t - SvPVX_const(PL_formtarget));
                *t = '\0';
-               sv_utf8_upgrade(PL_formtarget);
-               SvGROW(PL_formtarget, SvCUR(PL_formtarget) + fudge + 1);
+               sv_utf8_upgrade_flags_grow(PL_formtarget, SV_GMAGIC, fudge + 1);
                t = SvEND(PL_formtarget);
                targ_is_utf8 = TRUE;
            }
@@ -692,8 +694,8 @@ PP(pp_formline)
                    if (!targ_is_utf8) {
                        SvCUR_set(PL_formtarget, t - SvPVX_const(PL_formtarget));
                        *t = '\0';
-                       sv_utf8_upgrade(PL_formtarget);
-                       SvGROW(PL_formtarget, SvCUR(PL_formtarget) + fudge + 1);
+                       sv_utf8_upgrade_flags_grow(PL_formtarget, SV_GMAGIC,
+                                                                   fudge + 1);
                        t = SvEND(PL_formtarget);
                        targ_is_utf8 = TRUE;
                    }
@@ -763,51 +765,76 @@ PP(pp_formline)
 
        case FF_LINESNGL:
            chopspace = 0;
-           oneline = TRUE;
-           goto ff_line;
        case FF_LINEGLOB:
-           oneline = FALSE;
-       ff_line:
            {
+               const bool oneline = fpc[-1] == FF_LINESNGL;
                const char *s = item = SvPV_const(sv, len);
+               item_is_utf8 = DO_UTF8(sv);
                itemsize = len;
-               if ((item_is_utf8 = DO_UTF8(sv)))
-                   itemsize = sv_len_utf8(sv);
                if (itemsize) {
-                   bool chopped = FALSE;
+                   STRLEN to_copy = itemsize;
                    const char *const send = s + len;
+                   const U8 *source = (const U8 *) s;
+                   U8 *tmp = NULL;
+
                    gotsome = TRUE;
                    chophere = s + itemsize;
                    while (s < send) {
                        if (*s++ == '\n') {
                            if (oneline) {
-                               chopped = TRUE;
+                               to_copy = s - SvPVX_const(sv) - 1;
                                chophere = s;
                                break;
                            } else {
                                if (s == send) {
                                    itemsize--;
-                                   chopped = TRUE;
+                                   to_copy--;
                                } else
                                    lines++;
                            }
                        }
                    }
-                   SvCUR_set(PL_formtarget, t - SvPVX_const(PL_formtarget));
-                   if (targ_is_utf8)
-                       SvUTF8_on(PL_formtarget);
-                   if (oneline) {
-                       SvCUR_set(sv, chophere - item);
-                       sv_catsv(PL_formtarget, sv);
-                       SvCUR_set(sv, itemsize);
-                   } else
-                       sv_catsv(PL_formtarget, sv);
-                   if (chopped)
-                       SvCUR_set(PL_formtarget, SvCUR(PL_formtarget) - 1);
-                   SvGROW(PL_formtarget, SvCUR(PL_formtarget) + fudge + 1);
+                   if (targ_is_utf8 && !item_is_utf8) {
+                       source = tmp = bytes_to_utf8(source, &to_copy);
+                       SvCUR_set(PL_formtarget,
+                                 t - SvPVX_const(PL_formtarget));
+                   } else {
+                       if (item_is_utf8 && !targ_is_utf8) {
+                           /* Upgrade targ to UTF8, and then we reduce it to
+                              a problem we have a simple solution for.  */
+                           SvCUR_set(PL_formtarget,
+                                     t - SvPVX_const(PL_formtarget));
+                           targ_is_utf8 = TRUE;
+                           /* Don't need get magic.  */
+                           sv_utf8_upgrade_nomg(PL_formtarget);
+                       } else {
+                           SvCUR_set(PL_formtarget,
+                                     t - SvPVX_const(PL_formtarget));
+                       }
+
+                       /* Easy. They agree.  */
+                       assert (item_is_utf8 == targ_is_utf8);
+                   }
+                   SvGROW(PL_formtarget,
+                          SvCUR(PL_formtarget) + to_copy + fudge + 1);
                    t = SvPVX(PL_formtarget) + SvCUR(PL_formtarget);
-                   if (item_is_utf8)
-                       targ_is_utf8 = TRUE;
+
+                   Copy(source, t, to_copy, char);
+                   t += to_copy;
+                   SvCUR_set(PL_formtarget, SvCUR(PL_formtarget) + to_copy);
+                   if (item_is_utf8) {
+                       if (SvGMAGICAL(sv)) {
+                           /* Mustn't call sv_pos_b2u() as it does a second
+                              mg_get(). Is this a bug? Do we need a _flags()
+                              variant? */
+                           itemsize = utf8_length(source, source + itemsize);
+                       } else {
+                           sv_pos_b2u(sv, &itemsize);
+                       }
+                       assert(!tmp);
+                   } else if (tmp) {
+                       Safefree(tmp);
+                   }
                }
                break;
            }
@@ -960,7 +987,7 @@ PP(pp_grepstart)
     if (PL_op->op_private & OPpGREP_LEX)
        PAD_SVl(PL_op->op_targ) = src;
     else
-       DEFSV = src;
+       DEFSV_set(src);
 
     PUTBACK;
     if (PL_op->op_type == OP_MAPSTART)
@@ -1071,7 +1098,7 @@ PP(pp_mapwhile)
        if (PL_op->op_private & OPpGREP_LEX)
            PAD_SVl(PL_op->op_targ) = src;
        else
-           DEFSV = src;
+           DEFSV_set(src);
 
        RETURNOP(cLOGOP->op_other);
     }
@@ -1128,7 +1155,7 @@ PP(pp_flip)
                RETURNOP(((LOGOP*)cUNOP->op_first)->op_other);
            }
        }
-       sv_setpvn(TARG, "", 0);
+       sv_setpvs(TARG, "");
        SETs(targ);
        RETURN;
     }
@@ -1224,14 +1251,17 @@ PP(pp_flop)
 
 static const char * const context_name[] = {
     "pseudo-block",
+    NULL, /* CXt_WHEN never actually needs "block" */
+    NULL, /* CXt_BLOCK never actually needs "block" */
+    NULL, /* CXt_GIVEN never actually needs "block" */
+    NULL, /* CXt_LOOP_FOR never actually needs "loop" */
+    NULL, /* CXt_LOOP_PLAIN never actually needs "loop" */
+    NULL, /* CXt_LOOP_LAZYSV never actually needs "loop" */
+    NULL, /* CXt_LOOP_LAZYIV never actually needs "loop" */
     "subroutine",
+    "format",
     "eval",
-    "loop",
     "substitution",
-    "block",
-    "format",
-    "given",
-    "when"
 };
 
 STATIC I32
@@ -1240,6 +1270,8 @@ S_dopoptolabel(pTHX_ const char *label)
     dVAR;
     register I32 i;
 
+    PERL_ARGS_ASSERT_DOPOPTOLABEL;
+
     for (i = cxstack_ix; i >= 0; i--) {
        register const PERL_CONTEXT * const cx = &cxstack[i];
        switch (CxTYPE(cx)) {
@@ -1248,14 +1280,14 @@ S_dopoptolabel(pTHX_ const char *label)
        case CXt_FORMAT:
        case CXt_EVAL:
        case CXt_NULL:
-       case CXt_GIVEN:
-       case CXt_WHEN:
            if (ckWARN(WARN_EXITING))
                Perl_warner(aTHX_ packWARN(WARN_EXITING), "Exiting %s via %s",
                        context_name[CxTYPE(cx)], OP_NAME(PL_op));
            if (CxTYPE(cx) == CXt_NULL)
                return -1;
            break;
+       case CXt_LOOP_LAZYIV:
+       case CXt_LOOP_LAZYSV:
        case CXt_LOOP_FOR:
        case CXt_LOOP_PLAIN:
            if ( !CxLABEL(cx) || strNE(label, CxLABEL(cx)) ) {
@@ -1320,6 +1352,9 @@ S_dopoptosub_at(pTHX_ const PERL_CONTEXT *cxstk, I32 startingblock)
 {
     dVAR;
     I32 i;
+
+    PERL_ARGS_ASSERT_DOPOPTOSUB_AT;
+
     for (i = startingblock; i >= 0; i--) {
        register const PERL_CONTEXT * const cx = &cxstk[i];
        switch (CxTYPE(cx)) {
@@ -1372,6 +1407,8 @@ S_dopoptoloop(pTHX_ I32 startingblock)
            if ((CxTYPE(cx)) == CXt_NULL)
                return -1;
            break;
+       case CXt_LOOP_LAZYIV:
+       case CXt_LOOP_LAZYSV:
        case CXt_LOOP_FOR:
        case CXt_LOOP_PLAIN:
            DEBUG_l( Perl_deb(aTHX_ "(Found loop #%ld)\n", (long)i));
@@ -1397,6 +1434,8 @@ S_dopoptogiven(pTHX_ I32 startingblock)
        case CXt_LOOP_PLAIN:
            assert(!CxFOREACHDEF(cx));
            break;
+       case CXt_LOOP_LAZYIV:
+       case CXt_LOOP_LAZYSV:
        case CXt_LOOP_FOR:
            if (CxFOREACHDEF(cx)) {
                DEBUG_l( Perl_deb(aTHX_ "(Found foreach #%ld)\n", (long)i));
@@ -1448,6 +1487,8 @@ Perl_dounwind(pTHX_ I32 cxix)
        case CXt_EVAL:
            POPEVAL(cx);
            break;
+       case CXt_LOOP_LAZYIV:
+       case CXt_LOOP_LAZYSV:
        case CXt_LOOP_FOR:
        case CXt_LOOP_PLAIN:
            POPLOOP(cx);
@@ -1467,6 +1508,9 @@ void
 Perl_qerror(pTHX_ SV *err)
 {
     dVAR;
+
+    PERL_ARGS_ASSERT_QERROR;
+
     if (PL_in_eval)
        sv_catsv(ERRSV, err);
     else if (PL_errors)
@@ -1492,7 +1536,7 @@ Perl_die_where(pTHX_ const char *message, STRLEN msglen)
                SV * const err = ERRSV;
                const char *e = NULL;
                if (!SvPOK(err))
-                   sv_setpvn(err,"",0);
+                   sv_setpvs(err,"");
                else if (SvCUR(err) >= sizeof(prefix)+msglen-1) {
                    STRLEN len;
                    e = SvPV_const(err, len);
@@ -1506,7 +1550,8 @@ Perl_die_where(pTHX_ const char *message, STRLEN msglen)
                    sv_catpvn(err, message, msglen);
                    if (ckWARN(WARN_MISC)) {
                        const STRLEN start = SvCUR(err)-msglen-sizeof(prefix)+1;
-                       Perl_warner(aTHX_ packWARN(WARN_MISC), SvPVX_const(err)+start);
+                       Perl_warner(aTHX_ packWARN(WARN_MISC), "%s",
+                               SvPVX_const(err)+start);
                    }
                }
            }
@@ -1704,9 +1749,8 @@ PP(pp_caller)
        const int off = AvARRAY(ary) - AvALLOC(ary);
 
        if (!PL_dbargs) {
-           GV* const tmpgv = gv_fetchpvs("DB::args", GV_ADD, SVt_PVAV);
-           PL_dbargs = GvAV(gv_AVadd(tmpgv));
-           GvMULTI_on(tmpgv);
+           PL_dbargs = GvAV(gv_AVadd(gv_fetchpvs("DB::args", GV_ADDMULTI,
+                                                 SVt_PVAV)));
            AvREAL_off(PL_dbargs);      /* XXX should be REIFY (see av.h) */
        }
 
@@ -1731,7 +1775,7 @@ PP(pp_caller)
            /* Get the bit mask for $warnings::Bits{all}, because
             * it could have been extended by warnings::register */
            SV **bits_all;
-           HV * const bits = get_hv("warnings::Bits", FALSE);
+           HV * const bits = get_hv("warnings::Bits", 0);
            if (bits && (bits_all=hv_fetchs(bits, "all", FALSE))) {
                mask = newSVsv(*bits_all);
            }
@@ -1746,8 +1790,8 @@ PP(pp_caller)
 
     PUSHs(cx->blk_oldcop->cop_hints_hash ?
          sv_2mortal(newRV_noinc(
-           (SV*)Perl_refcounted_he_chain_2hv(aTHX_
-                                             cx->blk_oldcop->cop_hints_hash)))
+                                MUTABLE_SV(Perl_refcounted_he_chain_2hv(aTHX_
+                                             cx->blk_oldcop->cop_hints_hash))))
          : &PL_sv_undef);
     RETURN;
 }
@@ -1827,9 +1871,9 @@ PP(pp_enteriter)
     register PERL_CONTEXT *cx;
     const I32 gimme = GIMME_V;
     SV **svp;
-    U16 cxtype = CXt_LOOP_FOR;
+    U8 cxtype = CXt_LOOP_FOR;
 #ifdef USE_ITHREADS
-    void *iterdata;
+    PAD *iterdata;
 #endif
 
     ENTER;
@@ -1841,22 +1885,20 @@ PP(pp_enteriter)
            SAVESETSVFLAGS(PAD_SVl(PL_op->op_targ),
                    SVs_PADSTALE, SVs_PADSTALE);
        }
+       SAVEPADSVANDMORTALIZE(PL_op->op_targ);
 #ifndef USE_ITHREADS
        svp = &PAD_SVl(PL_op->op_targ);         /* "my" variable */
-       SAVESPTR(*svp);
 #else
-       SAVEPADSV(PL_op->op_targ);
-       iterdata = INT2PTR(void*, PL_op->op_targ);
-       cxtype |= CXp_PADVAR;
+       iterdata = NULL;
 #endif
     }
     else {
-       GV * const gv = (GV*)POPs;
+       GV * const gv = MUTABLE_GV(POPs);
        svp = &GvSV(gv);                        /* symbol table variable */
        SAVEGENERICSV(*svp);
        *svp = newSV(0);
 #ifdef USE_ITHREADS
-       iterdata = (void*)gv;
+       iterdata = (PAD*)gv;
 #endif
     }
 
@@ -1867,18 +1909,23 @@ PP(pp_enteriter)
 
     PUSHBLOCK(cx, cxtype, SP);
 #ifdef USE_ITHREADS
-    PUSHLOOP_FOR(cx, iterdata, MARK);
+    PUSHLOOP_FOR(cx, iterdata, MARK, PL_op->op_targ);
 #else
-    PUSHLOOP_FOR(cx, svp, MARK);
+    PUSHLOOP_FOR(cx, svp, MARK, 0);
 #endif
     if (PL_op->op_flags & OPf_STACKED) {
-       cx->blk_loop.iterary = (AV*)SvREFCNT_inc(POPs);
-       if (SvTYPE(cx->blk_loop.iterary) != SVt_PVAV) {
+       SV *maybe_ary = POPs;
+       if (SvTYPE(maybe_ary) != SVt_PVAV) {
            dPOPss;
-           SV * const right = (SV*)cx->blk_loop.iterary;
+           SV * const right = maybe_ary;
            SvGETMAGIC(sv);
            SvGETMAGIC(right);
            if (RANGE_IS_NUMERIC(sv,right)) {
+               cx->cx_type &= ~CXTYPEMASK;
+               cx->cx_type |= CXt_LOOP_LAZYIV;
+               /* Make sure that no-one re-orders cop.h and breaks our
+                  assumptions */
+               assert(CxTYPE(cx) == CXt_LOOP_LAZYIV);
 #ifdef NV_PRESERVES_UV
                if ((SvOK(sv) && ((SvNV(sv) < (NV)IV_MIN) ||
                                  (SvNV(sv) > (NV)IV_MAX)))
@@ -1899,33 +1946,50 @@ PP(pp_enteriter)
                                         (SvNV(right) > (NV)UV_MAX))))))
 #endif
                    DIE(aTHX_ "Range iterator outside integer range");
-               cx->blk_loop.iterix = SvIV(sv);
-               cx->blk_loop.itermax = SvIV(right);
+               cx->blk_loop.state_u.lazyiv.cur = SvIV(sv);
+               cx->blk_loop.state_u.lazyiv.end = SvIV(right);
 #ifdef DEBUGGING
                /* for correct -Dstv display */
                cx->blk_oldsp = sp - PL_stack_base;
 #endif
            }
            else {
-               cx->blk_loop.iterlval = newSVsv(sv);
-               (void) SvPV_force_nolen(cx->blk_loop.iterlval);
+               cx->cx_type &= ~CXTYPEMASK;
+               cx->cx_type |= CXt_LOOP_LAZYSV;
+               /* Make sure that no-one re-orders cop.h and breaks our
+                  assumptions */
+               assert(CxTYPE(cx) == CXt_LOOP_LAZYSV);
+               cx->blk_loop.state_u.lazysv.cur = newSVsv(sv);
+               cx->blk_loop.state_u.lazysv.end = right;
+               SvREFCNT_inc(right);
+               (void) SvPV_force_nolen(cx->blk_loop.state_u.lazysv.cur);
+               /* This will do the upgrade to SVt_PV, and warn if the value
+                  is uninitialised.  */
                (void) SvPV_nolen_const(right);
+               /* Doing this avoids a check every time in pp_iter in pp_hot.c
+                  to replace !SvOK() with a pointer to "".  */
+               if (!SvOK(right)) {
+                   SvREFCNT_dec(right);
+                   cx->blk_loop.state_u.lazysv.end = &PL_sv_no;
+               }
            }
        }
-       else if (PL_op->op_private & OPpITER_REVERSED) {
-           cx->blk_loop.itermax = 0;
-           cx->blk_loop.iterix = AvFILL(cx->blk_loop.iterary) + 1;
-
+       else /* SvTYPE(maybe_ary) == SVt_PVAV */ {
+           cx->blk_loop.state_u.ary.ary = MUTABLE_AV(maybe_ary);
+           SvREFCNT_inc(maybe_ary);
+           cx->blk_loop.state_u.ary.ix =
+               (PL_op->op_private & OPpITER_REVERSED) ?
+               AvFILL(cx->blk_loop.state_u.ary.ary) + 1 :
+               -1;
        }
     }
-    else {
-       cx->blk_loop.iterary = PL_curstack;
+    else { /* iterating over items on the stack */
+       cx->blk_loop.state_u.ary.ary = NULL; /* means to use the stack */
        if (PL_op->op_private & OPpITER_REVERSED) {
-           cx->blk_loop.itermax = MARK - PL_stack_base + 1;
-           cx->blk_loop.iterix = cx->blk_oldsp + 1;
+           cx->blk_loop.state_u.ary.ix = cx->blk_oldsp + 1;
        }
        else {
-           cx->blk_loop.iterix = MARK - PL_stack_base;
+           cx->blk_loop.state_u.ary.ix = MARK - PL_stack_base;
        }
     }
 
@@ -2108,8 +2172,9 @@ PP(pp_return)
     PL_curpm = newpm;  /* ... and pop $1 et al */
 
     LEAVESUB(sv);
-    if (clear_errsv)
-       sv_setpvn(ERRSV,"",0);
+    if (clear_errsv) {
+       CLEAR_ERRSV();
+    }
     return retop;
 }
 
@@ -2145,6 +2210,8 @@ PP(pp_last)
     cxstack_ix++; /* temporarily protect top context */
     mark = newsp;
     switch (CxTYPE(cx)) {
+    case CXt_LOOP_LAZYIV:
+    case CXt_LOOP_LAZYSV:
     case CXt_LOOP_FOR:
     case CXt_LOOP_PLAIN:
        pop2 = CxTYPE(cx);
@@ -2189,7 +2256,9 @@ PP(pp_last)
     cxstack_ix--;
     /* Stack values are safe: */
     switch (pop2) {
+    case CXt_LOOP_LAZYIV:
     case CXt_LOOP_PLAIN:
+    case CXt_LOOP_LAZYSV:
     case CXt_LOOP_FOR:
        POPLOOP(cx);    /* release loop vars ... */
        LEAVE;
@@ -2280,6 +2349,8 @@ S_dofindlabel(pTHX_ OP *o, const char *label, OP **opstack, OP **oplimit)
     OP **ops = opstack;
     static const char too_deep[] = "Target of goto is too deeply nested";
 
+    PERL_ARGS_ASSERT_DOFINDLABEL;
+
     if (ops >= oplimit)
        Perl_croak(aTHX_ too_deep);
     if (o->op_type == OP_LEAVE ||
@@ -2298,7 +2369,7 @@ S_dofindlabel(pTHX_ OP *o, const char *label, OP **opstack, OP **oplimit)
        /* First try all the kids at this level, since that's likeliest. */
        for (kid = cUNOPo->op_first; kid; kid = kid->op_sibling) {
            if ((kid->op_type == OP_NEXTSTATE || kid->op_type == OP_DBSTATE) &&
-                   kCOP->cop_label && strEQ(kCOP->cop_label, label))
+                   CopLABEL(kCOP) && strEQ(CopLABEL(kCOP), label))
                return kid;
        }
        for (kid = cUNOPo->op_first; kid; kid = kid->op_sibling) {
@@ -2340,7 +2411,7 @@ PP(pp_goto)
        if (SvROK(sv) && SvTYPE(SvRV(sv)) == SVt_PVCV) {
            I32 cxix;
            register PERL_CONTEXT *cx;
-           CV* cv = (CV*)SvRV(sv);
+           CV *cv = MUTABLE_CV(SvRV(sv));
            SV** mark;
            I32 items = 0;
            I32 oldsave;
@@ -2402,7 +2473,7 @@ PP(pp_goto)
                    av = newAV();
                    av_extend(av, items-1);
                    AvREIFY_only(av);
-                   PAD_SVl(0) = (SV*)(cx->blk_sub.argarray = av);
+                   PAD_SVl(0) = MUTABLE_SV(cx->blk_sub.argarray = av);
                }
            }
            else if (CvISXSUB(cv)) {    /* put GvAV(defgv) back onto stack */
@@ -2463,10 +2534,10 @@ PP(pp_goto)
                PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));
                if (CxHASARGS(cx))
                {
-                   AV* const av = (AV*)PAD_SVl(0);
+                   AV *const av = MUTABLE_AV(PAD_SVl(0));
 
                    cx->blk_sub.savearray = GvAV(PL_defgv);
-                   GvAV(PL_defgv) = (AV*)SvREFCNT_inc_simple(av);
+                   GvAV(PL_defgv) = MUTABLE_AV(SvREFCNT_inc_simple(av));
                    CX_CURPAD_SAVE(cx->blk_sub);
                    cx->blk_sub.argarray = av;
 
@@ -2501,10 +2572,10 @@ PP(pp_goto)
                if (PERLDB_SUB) {       /* Checking curstash breaks DProf. */
                    Perl_get_db_sub(aTHX_ NULL, cv);
                    if (PERLDB_GOTO) {
-                       CV * const gotocv = get_cv("DB::goto", FALSE);
+                       CV * const gotocv = get_cvs("DB::goto", 0);
                        if (gotocv) {
                            PUSHMARK( PL_stack_sp );
-                           call_sv((SV*)gotocv, G_SCALAR | G_NODEBUG);
+                           call_sv(MUTABLE_SV(gotocv), G_SCALAR | G_NODEBUG);
                            PL_stack_sp--;
                        }
                    }
@@ -2548,8 +2619,12 @@ PP(pp_goto)
                    break;
                 }
                 /* else fall through */
+           case CXt_LOOP_LAZYIV:
+           case CXt_LOOP_LAZYSV:
            case CXt_LOOP_FOR:
            case CXt_LOOP_PLAIN:
+           case CXt_GIVEN:
+           case CXt_WHEN:
                gotoprobe = cx->blk_oldcop->op_sibling;
                break;
            case CXt_SUBST:
@@ -2681,11 +2756,13 @@ S_save_lines(pTHX_ AV *array, SV *sv)
     const char * const send = SvPVX_const(sv) + SvCUR(sv);
     I32 line = 1;
 
+    PERL_ARGS_ASSERT_SAVE_LINES;
+
     while (s && s < send) {
        const char *t;
        SV * const tmpstr = newSV_type(SVt_PVMG);
 
-       t = strchr(s, '\n');
+       t = (const char *)memchr(s, '\n', send - s);
        if (t)
            t++;
        else
@@ -2768,6 +2845,8 @@ Perl_sv_compile_2op(pTHX_ SV *sv, OP** startop, const char *code, PAD** padp)
     CV* runcv = NULL;  /* initialise to avoid compiler warnings */
     STRLEN len;
 
+    PERL_ARGS_ASSERT_SV_COMPILE_2OP;
+
     ENTER;
     lex_start(sv, NULL, FALSE);
     SAVETMPS;
@@ -2815,7 +2894,7 @@ Perl_sv_compile_2op(pTHX_ SV *sv, OP** startop, const char *code, PAD** padp)
     PL_op->op_type = OP_ENTEREVAL;
     PL_op->op_flags = 0;                       /* Avoid uninit warning. */
     PUSHBLOCK(cx, CXt_EVAL|(IN_PERL_COMPILETIME ? 0 : CXp_REAL), SP);
-    PUSHEVAL(cx, 0, NULL);
+    PUSHEVAL(cx, 0);
 
     if (runtime)
        (void) doeval(G_SCALAR, startop, runcv, PL_curcop->cop_seq);
@@ -2828,7 +2907,7 @@ Perl_sv_compile_2op(pTHX_ SV *sv, OP** startop, const char *code, PAD** padp)
     (*startop)->op_ppaddr = PL_ppaddr[OP_NULL];
     lex_end();
     /* XXX DAPM do this properly one year */
-    *padp = (AV*)SvREFCNT_inc_simple(PL_comppad);
+    *padp = MUTABLE_AV(SvREFCNT_inc_simple(PL_comppad));
     LEAVE;
     if (IN_PERL_COMPILETIME)
        CopHINTS_set(&PL_compiling, PL_hints);
@@ -2905,13 +2984,13 @@ S_doeval(pTHX_ int gimme, OP** startop, CV* outside, U32 seq)
     PUSHMARK(SP);
 
     SAVESPTR(PL_compcv);
-    PL_compcv = (CV*)newSV_type(SVt_PVCV);
+    PL_compcv = MUTABLE_CV(newSV_type(SVt_PVCV));
     CvEVAL_on(PL_compcv);
     assert(CxTYPE(&cxstack[cxstack_ix]) == CXt_EVAL);
     cxstack[cxstack_ix].blk_eval.cv = PL_compcv;
 
     CvOUTSIDE_SEQ(PL_compcv) = seq;
-    CvOUTSIDE(PL_compcv) = (CV*)SvREFCNT_inc_simple(outside);
+    CvOUTSIDE(PL_compcv) = MUTABLE_CV(SvREFCNT_inc_simple(outside));
 
     /* set up a scratch pad */
 
@@ -2949,7 +3028,7 @@ S_doeval(pTHX_ int gimme, OP** startop, CV* outside, U32 seq)
     if (saveop && (saveop->op_type != OP_REQUIRE) && (saveop->op_flags & OPf_SPECIAL))
        PL_in_eval |= EVAL_KEEPERR;
     else
-       sv_setpvn(ERRSV,"",0);
+       CLEAR_ERRSV();
     if (yyparse() || PL_parser->error_count || !PL_eval_root) {
        SV **newsp;                     /* Used by POPBLOCK. */
        PERL_CONTEXT *cx = &cxstack[cxstack_ix];
@@ -2967,7 +3046,7 @@ S_doeval(pTHX_ int gimme, OP** startop, CV* outside, U32 seq)
            POPEVAL(cx);
        }
        lex_end();
-       LEAVE;
+       LEAVE; /* pp_entereval knows about this LEAVE.  */
 
        msg = SvPVx_nolen_const(ERRSV);
        if (optype == OP_REQUIRE) {
@@ -3018,13 +3097,13 @@ S_doeval(pTHX_ int gimme, OP** startop, CV* outside, U32 seq)
 
     /* Register with debugger: */
     if (PERLDB_INTER && saveop && saveop->op_type == OP_REQUIRE) {
-       CV * const cv = get_cv("DB::postponed", FALSE);
+       CV * const cv = get_cvs("DB::postponed", 0);
        if (cv) {
            dSP;
            PUSHMARK(SP);
-           XPUSHs((SV*)CopFILEGV(&PL_compiling));
+           XPUSHs(MUTABLE_SV(CopFILEGV(&PL_compiling)));
            PUTBACK;
-           call_sv((SV*)cv, G_DISCARD);
+           call_sv(MUTABLE_SV(cv), G_DISCARD);
        }
     }
 
@@ -3048,6 +3127,8 @@ S_check_type_and_open(pTHX_ const char *name)
     Stat_t st;
     const int st_rc = PerlLIO_stat(name, &st);
 
+    PERL_ARGS_ASSERT_CHECK_TYPE_AND_OPEN;
+
     if (st_rc < 0 || S_ISDIR(st.st_mode) || S_ISBLK(st.st_mode)) {
        return NULL;
     }
@@ -3061,6 +3142,8 @@ S_doopen_pm(pTHX_ const char *name, const STRLEN namelen)
 {
     PerlIO *fp;
 
+    PERL_ARGS_ASSERT_DOOPEN_PM;
+
     if (namelen > 3 && memEQs(name + namelen - 3, 3, ".pm")) {
        SV *const pmcsv = newSV(namelen + 2);
        char *const pmc = SvPVX(pmcsv);
@@ -3126,14 +3209,14 @@ PP(pp_require)
                I32 first = 0;
                AV *lav;
                SV * const req = SvRV(sv);
-               SV * const pv = *hv_fetchs((HV*)req, "original", FALSE);
+               SV * const pv = *hv_fetchs(MUTABLE_HV(req), "original", FALSE);
 
                /* get the left hand term */
-               lav = (AV *)SvRV(*hv_fetchs((HV*)req, "version", FALSE));
+               lav = MUTABLE_AV(SvRV(*hv_fetchs(MUTABLE_HV(req), "version", FALSE)));
 
                first  = SvIV(*av_fetch(lav,0,0));
                if (   first > (int)PERL_REVISION    /* probably 'use 6.0' */
-                   || hv_exists((HV*)req, "qv", 2 ) /* qv style */
+                   || hv_exists(MUTABLE_HV(req), "qv", 2 ) /* qv style */
                    || av_len(lav) > 1               /* FP with > 3 digits */
                    || strstr(SvPVX(pv),".0")        /* FP with leading 0 */
                   ) {
@@ -3173,6 +3256,11 @@ PP(pp_require)
            Perl_load_module(aTHX_ 0, newSVpvs("feature"), NULL, importsv, NULL);
            LEAVE;
        }
+       /* If a version >= 5.11.0 is requested, strictures are on by default! */
+       if (PL_compcv &&
+               vcmp(sv, sv_2mortal(upg_version(newSVnv(5.011000), FALSE))) >= 0) {
+           PL_hints |= (HINT_STRICT_REFS | HINT_STRICT_SUBS | HINT_STRICT_VARS);
+       }
 
        RETPUSHYES;
     }
@@ -3220,17 +3308,6 @@ PP(pp_require)
        tryname = name;
        tryrsfp = doopen_pm(name, len);
     }
-#ifdef MACOS_TRADITIONAL
-    if (!tryrsfp) {
-       char newname[256];
-
-       MacPerl_CanonDir(name, newname, 1);
-       if (path_is_absolute(newname)) {
-           tryname = newname;
-           tryrsfp = doopen_pm(newname, strlen(newname));
-       }
-    }
-#endif
     if (!tryrsfp) {
        AV * const ar = GvAVn(PL_incgv);
        I32 i;
@@ -3242,7 +3319,7 @@ PP(pp_require)
            for (i = 0; i <= AvFILL(ar); i++) {
                SV * const dirsv = *av_fetch(ar, i, TRUE);
 
-               if (SvTIED_mg((SV*)ar, PERL_MAGIC_tied))
+               if (SvTIED_mg((const SV *)ar, PERL_MAGIC_tied))
                    mg_get(dirsv);
                if (SvROK(dirsv)) {
                    int count;
@@ -3252,7 +3329,7 @@ PP(pp_require)
                    if (SvTYPE(SvRV(loader)) == SVt_PVAV
                        && !sv_isobject(loader))
                    {
-                       loader = *av_fetch((AV *)SvRV(loader), 0, TRUE);
+                       loader = *av_fetch(MUTABLE_AV(SvRV(loader)), 0, TRUE);
                    }
 
                    Perl_sv_setpvf(aTHX_ namesv, "/loader/0x%"UVxf"/%s",
@@ -3296,12 +3373,12 @@ PP(pp_require)
                            }
                        }
 
-                       if (SvROK(arg) && SvTYPE(SvRV(arg)) == SVt_PVGV) {
+                       if (SvROK(arg) && isGV_with_GP(SvRV(arg))) {
                            arg = SvRV(arg);
                        }
 
-                       if (SvTYPE(arg) == SVt_PVGV) {
-                           IO * const io = GvIO((GV *)arg);
+                       if (isGV_with_GP(arg)) {
+                           IO * const io = GvIO((const GV *)arg);
 
                            ++filter_has_file;
 
@@ -3361,12 +3438,6 @@ PP(pp_require)
                }
                else {
                  if (!path_is_absolute(name)
-#ifdef MACOS_TRADITIONAL
-                       /* We consider paths of the form :a:b ambiguous and interpret them first
-                          as global then as local
-                       */
-                       || (*name == ':' && name[1] != ':' && strchr(name+2, ':'))
-#endif
                  ) {
                    const char *dir;
                    STRLEN dirlen;
@@ -3378,21 +3449,14 @@ PP(pp_require)
                        dirlen = 0;
                    }
 
-#ifdef MACOS_TRADITIONAL
-                   char buf1[256];
-                   char buf2[256];
-
-                   MacPerl_CanonDir(name, buf2, 1);
-                   Perl_sv_setpvf(aTHX_ namesv, "%s%s", MacPerl_CanonDir(dir, buf1, 0), buf2+(buf2[0] == ':'));
-#else
-#  ifdef VMS
+#ifdef VMS
                    char *unixdir;
                    if ((unixdir = tounixpath(dir, NULL)) == NULL)
                        continue;
                    sv_setpv(namesv, unixdir);
                    sv_catpv(namesv, unixname);
-#  else
-#    ifdef __SYMBIAN32__
+#else
+#  ifdef __SYMBIAN32__
                    if (PL_origfilename[0] &&
                        PL_origfilename[1] == ':' &&
                        !(dir[0] && dir[1] == ':'))
@@ -3404,7 +3468,7 @@ PP(pp_require)
                        Perl_sv_setpvf(aTHX_ namesv,
                                       "%s\\%s",
                                       dir, name);
-#    else
+#  else
                    /* The equivalent of                    
                       Perl_sv_setpvf(aTHX_ namesv, "%s/%s", dir, name);
                       but without the need to parse the format string, or
@@ -3425,15 +3489,16 @@ PP(pp_require)
                        /* Don't even actually have to turn SvPOK_on() as we
                           access it directly with SvPVX() below.  */
                    }
-#    endif
 #  endif
 #endif
                    TAINT_PROPER("require");
                    tryname = SvPVX_const(namesv);
                    tryrsfp = doopen_pm(tryname, SvCUR(namesv));
                    if (tryrsfp) {
-                       if (tryname[0] == '.' && tryname[1] == '/')
-                           tryname += 2;
+                       if (tryname[0] == '.' && tryname[1] == '/') {
+                           ++tryname;
+                           while (*++tryname == '/');
+                       }
                        break;
                    }
                    else if (errno == EMFILE)
@@ -3503,6 +3568,8 @@ PP(pp_require)
 
     SAVEHINTS();
     PL_hints = 0;
+    hv_clear(GvHV(PL_hintgv));
+
     SAVECOMPILEWARNINGS();
     if (PL_dowarn & G_WARN_ALL_ON)
         PL_compiling.cop_warnings = pWARN_ALL ;
@@ -3514,14 +3581,14 @@ PP(pp_require)
     if (filter_sub || filter_cache) {
        SV * const datasv = filter_add(S_run_user_filter, NULL);
        IoLINES(datasv) = filter_has_file;
-       IoTOP_GV(datasv) = (GV *)filter_state;
-       IoBOTTOM_GV(datasv) = (GV *)filter_sub;
-       IoFMT_GV(datasv) = (GV *)filter_cache;
+       IoTOP_GV(datasv) = MUTABLE_GV(filter_state);
+       IoBOTTOM_GV(datasv) = MUTABLE_GV(filter_sub);
+       IoFMT_GV(datasv) = MUTABLE_GV(filter_cache);
     }
 
     /* switch to eval mode */
     PUSHBLOCK(cx, CXt_EVAL, SP);
-    PUSHEVAL(cx, name, NULL);
+    PUSHEVAL(cx, name);
     cx->blk_eval.retop = PL_op->op_next;
 
     SAVECOPLINE(&PL_compiling);
@@ -3544,26 +3611,35 @@ PP(pp_require)
     return op;
 }
 
+/* This is a op added to hold the hints hash for
+   pp_entereval. The hash can be modified by the code
+   being eval'ed, so we return a copy instead. */
+
+PP(pp_hintseval)
+{
+    dVAR;
+    dSP;
+    mXPUSHs(MUTABLE_SV(Perl_hv_copy_hints_hv(aTHX_ MUTABLE_HV(cSVOP_sv))));
+    RETURN;
+}
+
+
 PP(pp_entereval)
 {
     dVAR; dSP;
     register PERL_CONTEXT *cx;
     SV *sv;
     const I32 gimme = GIMME_V;
-    const I32 was = PL_sub_generation;
+    const U32 was = PL_breakable_sub_gen;
     char tbuf[TYPE_DIGITS(long) + 12];
     char *tmpbuf = tbuf;
-    char *safestr;
     STRLEN len;
-    bool ok;
     CV* runcv;
     U32 seq;
     HV *saved_hh = NULL;
-    const char * const fakestr = "_<(eval )";
-    const int fakelen = 9 + 1;
-    
+
     if (PL_op->op_private & OPpEVAL_HAS_HH) {
-       saved_hh = (HV*) SvREFCNT_inc(POPs);
+       saved_hh = MUTABLE_HV(SvREFCNT_inc(POPs));
     }
     sv = POPs;
 
@@ -3595,12 +3671,13 @@ PP(pp_entereval)
        (i.e. before run-time proper). To work around the coredump that
        ensues, we always turn GvMULTI_on for any globals that were
        introduced within evals. See force_ident(). GSAR 96-10-12 */
-    safestr = savepvn(tmpbuf, len);
-    SAVEDELETE(PL_defstash, safestr, len);
     SAVEHINTS();
     PL_hints = PL_op->op_targ;
-    if (saved_hh)
+    if (saved_hh) {
+       /* SAVEHINTS created a new HV in PL_hintgv, which we need to GC */
+       SvREFCNT_dec(GvHV(PL_hintgv));
        GvHV(PL_hintgv) = saved_hh;
+    }
     SAVECOMPILEWARNINGS();
     PL_compiling.cop_warnings = DUP_WARNINGS(PL_curcop->cop_warnings);
     if (PL_compiling.cop_hints_hash) {
@@ -3620,21 +3697,37 @@ PP(pp_entereval)
     runcv = find_runcv(&seq);
 
     PUSHBLOCK(cx, (CXt_EVAL|CXp_REAL), SP);
-    PUSHEVAL(cx, 0, NULL);
+    PUSHEVAL(cx, 0);
     cx->blk_eval.retop = PL_op->op_next;
 
     /* prepare to compile string */
 
-    if (PERLDB_LINE && PL_curstash != PL_debstash)
+    if ((PERLDB_LINE || PERLDB_SAVESRC) && PL_curstash != PL_debstash)
        save_lines(CopFILEAV(&PL_compiling), PL_parser->linestr);
     PUTBACK;
-    ok = doeval(gimme, NULL, runcv, seq);
-    if (PERLDB_INTER && was != (I32)PL_sub_generation /* Some subs defined here. */
-       && ok) {
-       /* Copy in anything fake and short. */
-       my_strlcpy(safestr, fakestr, fakelen);
+
+    if (doeval(gimme, NULL, runcv, seq)) {
+       if (was != PL_breakable_sub_gen /* Some subs defined here. */
+           ? (PERLDB_LINE || PERLDB_SAVESRC)
+           :  PERLDB_SAVESRC_NOSUBS) {
+           /* Retain the filegv we created.  */
+       } else {
+           char *const safestr = savepvn(tmpbuf, len);
+           SAVEDELETE(PL_defstash, safestr, len);
+       }
+       return DOCATCH(PL_eval_start);
+    } else {
+       /* We have already left the scope set up earler thanks to the LEAVE
+          in doeval().  */
+       if (was != PL_breakable_sub_gen /* Some subs defined here. */
+           ? (PERLDB_LINE || PERLDB_SAVESRC)
+           :  PERLDB_SAVESRC_INVALID) {
+           /* Retain the filegv we created.  */
+       } else {
+           (void)hv_delete(PL_defstash, tmpbuf, len, G_DISCARD);
+       }
+       return PL_op->op_next;
     }
-    return ok ? DOCATCH(PL_eval_start) : PL_op->op_next;
 }
 
 PP(pp_leaveeval)
@@ -3698,8 +3791,9 @@ PP(pp_leaveeval)
     }
     else {
        LEAVE;
-       if (!(save_flags & OPf_SPECIAL))
-           sv_setpvn(ERRSV,"",0);
+       if (!(save_flags & OPf_SPECIAL)) {
+           CLEAR_ERRSV();
+       }
     }
 
     RETURNOP(retop);
@@ -3737,13 +3831,13 @@ Perl_create_eval_scope(pTHX_ U32 flags)
     SAVETMPS;
 
     PUSHBLOCK(cx, (CXt_EVAL|CXp_TRYBLOCK), PL_stack_sp);
-    PUSHEVAL(cx, 0, 0);
+    PUSHEVAL(cx, 0);
 
     PL_in_eval = EVAL_INEVAL;
     if (flags & G_KEEPERR)
        PL_in_eval |= EVAL_KEEPERR;
     else
-       sv_setpvn(ERRSV,"",0);
+       CLEAR_ERRSV();
     if (flags & G_FAKINGEVAL) {
        PL_eval_root = PL_op; /* Only needed so that goto works right. */
     }
@@ -3802,7 +3896,7 @@ PP(pp_leavetry)
     PL_curpm = newpm;  /* Don't pop $1 et al till now */
 
     LEAVE;
-    sv_setpvn(ERRSV,"",0);
+    CLEAR_ERRSV();
     RETURN;
 }
 
@@ -3815,13 +3909,7 @@ PP(pp_entergiven)
     ENTER;
     SAVETMPS;
 
-    if (PL_op->op_targ == 0) {
-       SV ** const defsv_p = &GvSV(PL_defgv);
-       *defsv_p = newSVsv(POPs);
-       SAVECLEARSV(*defsv_p);
-    }
-    else
-       sv_setsv(PAD_SV(PL_op->op_targ), POPs);
+    sv_setsv(PAD_SV(PL_op->op_targ), POPs);
 
     PUSHBLOCK(cx, CXt_GIVEN, SP);
     PUSHGIVEN(cx);
@@ -3857,8 +3945,11 @@ S_make_matcher(pTHX_ REGEXP *re)
 {
     dVAR;
     PMOP *matcher = (PMOP *) newPMOP(OP_MATCH, OPf_WANT_SCALAR | OPf_STACKED);
+
+    PERL_ARGS_ASSERT_MAKE_MATCHER;
+
     PM_SETRE(matcher, ReREFCNT_inc(re));
-    
+
     SAVEFREEOP((OP *) matcher);
     ENTER; SAVETMPS;
     SAVEOP();
@@ -3870,6 +3961,8 @@ S_matcher_matches_sv(pTHX_ PMOP *matcher, SV *sv)
 {
     dVAR;
     dSP;
+
+    PERL_ARGS_ASSERT_MATCHER_MATCHES_SV;
     
     PL_op = (OP *) matcher;
     XPUSHs(sv);
@@ -3883,7 +3976,10 @@ STATIC void
 S_destroy_matcher(pTHX_ PMOP *matcher)
 {
     dVAR;
+
+    PERL_ARGS_ASSERT_DESTROY_MATCHER;
     PERL_UNUSED_ARG(matcher);
+
     FREETMPS;
     LEAVE;
 }
@@ -3891,6 +3987,7 @@ S_destroy_matcher(pTHX_ PMOP *matcher)
 /* Do a smart match */
 PP(pp_smartmatch)
 {
+    DEBUG_M(Perl_deb(aTHX_ "Starting smart match resolution\n"));
     return do_smartmatch(NULL, NULL);
 }
 
@@ -3903,49 +4000,26 @@ S_do_smartmatch(pTHX_ HV *seen_this, HV *seen_other)
     dVAR;
     dSP;
     
+    bool object_on_left = FALSE;
     SV *e = TOPs;      /* e is for 'expression' */
     SV *d = TOPm1s;    /* d is for 'default', as in PL_defgv */
-    SV *This, *Other;  /* 'This' (and Other to match) to play with C++ */
-    REGEXP *this_regex, *other_regex;
-
-#   define NOT_EMPTY_PROTO(cv) (!SvPOK(cv) || SvCUR(cv) == 0)
-
-#   define SM_REF(type) ( \
-          (SvROK(d) && (SvTYPE(This = SvRV(d)) == SVt_##type) && (Other = e)) \
-       || (SvROK(e) && (SvTYPE(This = SvRV(e)) == SVt_##type) && (Other = d)))
-
-#   define SM_CV_NEP   /* Find a code ref without an empty prototype */ \
-       ((SvROK(d) && (SvTYPE(This = SvRV(d)) == SVt_PVCV)              \
-           && NOT_EMPTY_PROTO(This) && (Other = e))                    \
-       || (SvROK(e) && (SvTYPE(This = SvRV(e)) == SVt_PVCV)            \
-           && NOT_EMPTY_PROTO(This) && (Other = d)))
-
-#   define SM_REGEX ( \
-          (SvROK(d) && (SvTYPE(This = SvRV(d)) == SVt_REGEXP)          \
-       && (this_regex = (REGEXP*) This)                                \
-       && (Other = e))                                                 \
-    ||                                                                 \
-          (SvROK(e) && (SvTYPE(This = SvRV(e)) == SVt_REGEXP)          \
-       && (this_regex = (REGEXP*) This)                                \
-       && (Other = d)) )
-       
 
-#   define SM_OTHER_REF(type) \
-       (SvROK(Other) && SvTYPE(SvRV(Other)) == SVt_##type)
+    /* First of all, handle overload magic of the rightmost argument */
+    if (SvAMAGIC(e)) {
+       SV * tmpsv;
+       DEBUG_M(Perl_deb(aTHX_ "    applying rule Any-Object\n"));
+       DEBUG_M(Perl_deb(aTHX_ "        attempting overload\n"));
 
-#   define SM_OTHER_REGEX (SvROK(Other)                                        \
-       && (SvTYPE(SvRV(Other)) == SVt_REGEXP)                          \
-       && (other_regex = (REGEXP*) SvRV(Other)))
-
-
-#   define SM_SEEN_THIS(sv) hv_exists_ent(seen_this, \
-       sv_2mortal(newSViv(PTR2IV(sv))), 0)
-
-#   define SM_SEEN_OTHER(sv) hv_exists_ent(seen_other, \
-       sv_2mortal(newSViv(PTR2IV(sv))), 0)
+       tmpsv = amagic_call(d, e, smart_amg, 0);
+       if (tmpsv) {
+           SPAGAIN;
+           (void)POPs;
+           SETs(tmpsv);
+           RETURN;
+       }
+       DEBUG_M(Perl_deb(aTHX_ "        failed to run overload method; continuing...\n"));
+    }
 
-    tryAMAGICbinSET(smart, 0);
-    
     SP -= 2;   /* Pop the values */
 
     /* Take care only to invoke mg_get() once for each argument. 
@@ -3961,69 +4035,156 @@ S_do_smartmatch(pTHX_ HV *seen_this, HV *seen_other)
     if (SvGMAGICAL(e))
        e = sv_mortalcopy(e);
 
-    if (SM_CV_NEP) {
+    /* ~~ undef */
+    if (!SvOK(e)) {
+       DEBUG_M(Perl_deb(aTHX_ "    applying rule Any-undef\n"));
+       if (SvOK(d))
+           RETPUSHNO;
+       else
+           RETPUSHYES;
+    }
+
+    if (sv_isobject(e) && (SvTYPE(SvRV(e)) != SVt_REGEXP)) {
+       DEBUG_M(Perl_deb(aTHX_ "    applying rule Any-Object\n"));
+       Perl_croak(aTHX_ "Smart matching a non-overloaded object breaks encapsulation");
+    }
+    if (sv_isobject(d) && (SvTYPE(SvRV(d)) != SVt_REGEXP))
+       object_on_left = TRUE;
+
+    /* ~~ sub */
+    if (SvROK(e) && SvTYPE(SvRV(e)) == SVt_PVCV) {
        I32 c;
-       
-       if ( SM_OTHER_REF(PVCV) && NOT_EMPTY_PROTO(SvRV(Other)) )
-       {
-           if (This == SvRV(Other))
+       if (object_on_left) {
+           goto sm_any_sub; /* Treat objects like scalars */
+       }
+       else if (SvROK(d) && SvTYPE(SvRV(d)) == SVt_PVHV) {
+           /* Test sub truth for each key */
+           HE *he;
+           bool andedresults = TRUE;
+           HV *hv = (HV*) SvRV(d);
+           I32 numkeys = hv_iterinit(hv);
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Hash-CodeRef\n"));
+           if (numkeys == 0)
+               RETPUSHYES;
+           while ( (he = hv_iternext(hv)) ) {
+               DEBUG_M(Perl_deb(aTHX_ "        testing hash key...\n"));
+               ENTER;
+               SAVETMPS;
+               PUSHMARK(SP);
+               PUSHs(hv_iterkeysv(he));
+               PUTBACK;
+               c = call_sv(e, G_SCALAR);
+               SPAGAIN;
+               if (c == 0)
+                   andedresults = FALSE;
+               else
+                   andedresults = SvTRUEx(POPs) && andedresults;
+               FREETMPS;
+               LEAVE;
+           }
+           if (andedresults)
                RETPUSHYES;
            else
                RETPUSHNO;
        }
-       
-       ENTER;
-       SAVETMPS;
-       PUSHMARK(SP);
-       PUSHs(Other);
-       PUTBACK;
-       c = call_sv(This, G_SCALAR);
-       SPAGAIN;
-       if (c == 0)
-           PUSHs(&PL_sv_no);
-       else if (SvTEMP(TOPs))
-           SvREFCNT_inc_void(TOPs);
-       FREETMPS;
-       LEAVE;
-       RETURN;
+       else if (SvROK(d) && SvTYPE(SvRV(d)) == SVt_PVAV) {
+           /* Test sub truth for each element */
+           I32 i;
+           bool andedresults = TRUE;
+           AV *av = (AV*) SvRV(d);
+           const I32 len = av_len(av);
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Array-CodeRef\n"));
+           if (len == -1)
+               RETPUSHYES;
+           for (i = 0; i <= len; ++i) {
+               SV * const * const svp = av_fetch(av, i, FALSE);
+               DEBUG_M(Perl_deb(aTHX_ "        testing array element...\n"));
+               ENTER;
+               SAVETMPS;
+               PUSHMARK(SP);
+               if (svp)
+                   PUSHs(*svp);
+               PUTBACK;
+               c = call_sv(e, G_SCALAR);
+               SPAGAIN;
+               if (c == 0)
+                   andedresults = FALSE;
+               else
+                   andedresults = SvTRUEx(POPs) && andedresults;
+               FREETMPS;
+               LEAVE;
+           }
+           if (andedresults)
+               RETPUSHYES;
+           else
+               RETPUSHNO;
+       }
+       else {
+         sm_any_sub:
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Any-CodeRef\n"));
+           ENTER;
+           SAVETMPS;
+           PUSHMARK(SP);
+           PUSHs(d);
+           PUTBACK;
+           c = call_sv(e, G_SCALAR);
+           SPAGAIN;
+           if (c == 0)
+               PUSHs(&PL_sv_no);
+           else if (SvTEMP(TOPs))
+               SvREFCNT_inc_void(TOPs);
+           FREETMPS;
+           LEAVE;
+           RETURN;
+       }
     }
-    else if (SM_REF(PVHV)) {
-       if (SM_OTHER_REF(PVHV)) {
+    /* ~~ %hash */
+    else if (SvROK(e) && SvTYPE(SvRV(e)) == SVt_PVHV) {
+       if (object_on_left) {
+           goto sm_any_hash; /* Treat objects like scalars */
+       }
+       else if (!SvOK(d)) {
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Any-Hash ($a undef)\n"));
+           RETPUSHNO;
+       }
+       else if (SvROK(d) && SvTYPE(SvRV(d)) == SVt_PVHV) {
            /* Check that the key-sets are identical */
            HE *he;
-           HV *other_hv = (HV *) SvRV(Other);
+           HV *other_hv = MUTABLE_HV(SvRV(d));
            bool tied = FALSE;
            bool other_tied = FALSE;
            U32 this_key_count  = 0,
                other_key_count = 0;
-           
+           HV *hv = MUTABLE_HV(SvRV(e));
+
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Hash-Hash\n"));
            /* Tied hashes don't know how many keys they have. */
-           if (SvTIED_mg(This, PERL_MAGIC_tied)) {
+           if (SvTIED_mg((SV*)hv, PERL_MAGIC_tied)) {
                tied = TRUE;
            }
-           else if (SvTIED_mg((SV *) other_hv, PERL_MAGIC_tied)) {
+           else if (SvTIED_mg((const SV *)other_hv, PERL_MAGIC_tied)) {
                HV * const temp = other_hv;
-               other_hv = (HV *) This;
-               This  = (SV *) temp;
+               other_hv = hv;
+               hv = temp;
                tied = TRUE;
            }
-           if (SvTIED_mg((SV *) other_hv, PERL_MAGIC_tied))
+           if (SvTIED_mg((const SV *)other_hv, PERL_MAGIC_tied))
                other_tied = TRUE;
            
-           if (!tied && HvUSEDKEYS((HV *) This) != HvUSEDKEYS(other_hv))
+           if (!tied && HvUSEDKEYS((const HV *) hv) != HvUSEDKEYS(other_hv))
                RETPUSHNO;
 
            /* The hashes have the same number of keys, so it suffices
               to check that one is a subset of the other. */
-           (void) hv_iterinit((HV *) This);
-           while ( (he = hv_iternext((HV *) This)) ) {
-               I32 key_len;
-               char * const key = hv_iterkey(he, &key_len);
-               
+           (void) hv_iterinit(hv);
+           while ( (he = hv_iternext(hv)) ) {
+               SV *key = hv_iterkeysv(he);
+
+               DEBUG_M(Perl_deb(aTHX_ "        comparing hash key...\n"));
                ++ this_key_count;
                
-               if(!hv_exists(other_hv, key, key_len)) {
-                   (void) hv_iterinit((HV *) This);    /* reset iterator */
+               if(!hv_exists_ent(other_hv, key, 0)) {
+                   (void) hv_iterinit(hv);     /* reset iterator */
                    RETPUSHNO;
                }
            }
@@ -4041,50 +4202,79 @@ S_do_smartmatch(pTHX_ HV *seen_this, HV *seen_other)
            else
                RETPUSHYES;
        }
-       else if (SM_OTHER_REF(PVAV)) {
-           AV * const other_av = (AV *) SvRV(Other);
+       else if (SvROK(d) && SvTYPE(SvRV(d)) == SVt_PVAV) {
+           AV * const other_av = MUTABLE_AV(SvRV(d));
            const I32 other_len = av_len(other_av) + 1;
            I32 i;
+           HV *hv = MUTABLE_HV(SvRV(e));
 
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Array-Hash\n"));
            for (i = 0; i < other_len; ++i) {
                SV ** const svp = av_fetch(other_av, i, FALSE);
-               char *key;
-               STRLEN key_len;
-
+               DEBUG_M(Perl_deb(aTHX_ "        checking for key existence...\n"));
                if (svp) {      /* ??? When can this not happen? */
-                   key = SvPV(*svp, key_len);
-                   if (hv_exists((HV *) This, key, key_len))
+                   if (hv_exists_ent(hv, *svp, 0))
                        RETPUSHYES;
                }
            }
            RETPUSHNO;
        }
-       else if (SM_OTHER_REGEX) {
-           PMOP * const matcher = make_matcher(other_regex);
-           HE *he;
-
-           (void) hv_iterinit((HV *) This);
-           while ( (he = hv_iternext((HV *) This)) ) {
-               if (matcher_matches_sv(matcher, hv_iterkeysv(he))) {
-                   (void) hv_iterinit((HV *) This);
-                   destroy_matcher(matcher);
-                   RETPUSHYES;
+       else if (SvROK(d) && SvTYPE(SvRV(d)) == SVt_REGEXP) {
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Regex-Hash\n"));
+         sm_regex_hash:
+           {
+               PMOP * const matcher = make_matcher((REGEXP*) SvRV(d));
+               HE *he;
+               HV *hv = MUTABLE_HV(SvRV(e));
+
+               (void) hv_iterinit(hv);
+               while ( (he = hv_iternext(hv)) ) {
+                   DEBUG_M(Perl_deb(aTHX_ "        testing key against pattern...\n"));
+                   if (matcher_matches_sv(matcher, hv_iterkeysv(he))) {
+                       (void) hv_iterinit(hv);
+                       destroy_matcher(matcher);
+                       RETPUSHYES;
+                   }
                }
+               destroy_matcher(matcher);
+               RETPUSHNO;
            }
-           destroy_matcher(matcher);
-           RETPUSHNO;
        }
        else {
-           if (hv_exists_ent((HV *) This, Other, 0))
+         sm_any_hash:
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Any-Hash\n"));
+           if (hv_exists_ent(MUTABLE_HV(SvRV(e)), d, 0))
                RETPUSHYES;
            else
                RETPUSHNO;
        }
     }
-    else if (SM_REF(PVAV)) {
-       if (SM_OTHER_REF(PVAV)) {
-           AV *other_av = (AV *) SvRV(Other);
-           if (av_len((AV *) This) != av_len(other_av))
+    /* ~~ @array */
+    else if (SvROK(e) && SvTYPE(SvRV(e)) == SVt_PVAV) {
+       if (object_on_left) {
+           goto sm_any_array; /* Treat objects like scalars */
+       }
+       else if (SvROK(d) && SvTYPE(SvRV(d)) == SVt_PVHV) {
+           AV * const other_av = MUTABLE_AV(SvRV(e));
+           const I32 other_len = av_len(other_av) + 1;
+           I32 i;
+
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Hash-Array\n"));
+           for (i = 0; i < other_len; ++i) {
+               SV ** const svp = av_fetch(other_av, i, FALSE);
+
+               DEBUG_M(Perl_deb(aTHX_ "        testing for key existence...\n"));
+               if (svp) {      /* ??? When can this not happen? */
+                   if (hv_exists_ent(MUTABLE_HV(SvRV(d)), *svp, 0))
+                       RETPUSHYES;
+               }
+           }
+           RETPUSHNO;
+       }
+       if (SvROK(d) && SvTYPE(SvRV(d)) == SVt_PVAV) {
+           AV *other_av = MUTABLE_AV(SvRV(d));
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Array-Array\n"));
+           if (av_len(MUTABLE_AV(SvRV(e))) != av_len(other_av))
                RETPUSHNO;
            else {
                I32 i;
@@ -4092,22 +4282,24 @@ S_do_smartmatch(pTHX_ HV *seen_this, HV *seen_other)
 
                if (NULL == seen_this) {
                    seen_this = newHV();
-                   (void) sv_2mortal((SV *) seen_this);
+                   (void) sv_2mortal(MUTABLE_SV(seen_this));
                }
                if (NULL == seen_other) {
                    seen_this = newHV();
-                   (void) sv_2mortal((SV *) seen_other);
+                   (void) sv_2mortal(MUTABLE_SV(seen_other));
                }
                for(i = 0; i <= other_len; ++i) {
-                   SV * const * const this_elem = av_fetch((AV *)This, i, FALSE);
+                   SV * const * const this_elem = av_fetch(MUTABLE_AV(SvRV(e)), i, FALSE);
                    SV * const * const other_elem = av_fetch(other_av, i, FALSE);
 
                    if (!this_elem || !other_elem) {
                        if (this_elem || other_elem)
                            RETPUSHNO;
                    }
-                   else if (SM_SEEN_THIS(*this_elem)
-                        || SM_SEEN_OTHER(*other_elem))
+                   else if (hv_exists_ent(seen_this,
+                               sv_2mortal(newSViv(PTR2IV(*this_elem))), 0) ||
+                           hv_exists_ent(seen_other,
+                               sv_2mortal(newSViv(PTR2IV(*other_elem))), 0))
                    {
                        if (*this_elem != *other_elem)
                            RETPUSHNO;
@@ -4119,12 +4311,14 @@ S_do_smartmatch(pTHX_ HV *seen_this, HV *seen_other)
                        (void)hv_store_ent(seen_other,
                                sv_2mortal(newSViv(PTR2IV(*other_elem))),
                                &PL_sv_undef, 0);
-                       PUSHs(*this_elem);
                        PUSHs(*other_elem);
+                       PUSHs(*this_elem);
                        
                        PUTBACK;
+                       DEBUG_M(Perl_deb(aTHX_ "        recursively comparing array element...\n"));
                        (void) do_smartmatch(seen_this, seen_other);
                        SPAGAIN;
+                       DEBUG_M(Perl_deb(aTHX_ "        recursion finished\n"));
                        
                        if (!SvTRUEx(POPs))
                            RETPUSHNO;
@@ -4133,124 +4327,124 @@ S_do_smartmatch(pTHX_ HV *seen_this, HV *seen_other)
                RETPUSHYES;
            }
        }
-       else if (SM_OTHER_REGEX) {
-           PMOP * const matcher = make_matcher(other_regex);
-           const I32 this_len = av_len((AV *) This);
-           I32 i;
-
-           for(i = 0; i <= this_len; ++i) {
-               SV * const * const svp = av_fetch((AV *)This, i, FALSE);
-               if (svp && matcher_matches_sv(matcher, *svp)) {
-                   destroy_matcher(matcher);
-                   RETPUSHYES;
+       else if (SvROK(d) && SvTYPE(SvRV(d)) == SVt_REGEXP) {
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Regex-Array\n"));
+         sm_regex_array:
+           {
+               PMOP * const matcher = make_matcher((REGEXP*) SvRV(d));
+               const I32 this_len = av_len(MUTABLE_AV(SvRV(e)));
+               I32 i;
+
+               for(i = 0; i <= this_len; ++i) {
+                   SV * const * const svp = av_fetch(MUTABLE_AV(SvRV(e)), i, FALSE);
+                   DEBUG_M(Perl_deb(aTHX_ "        testing element against pattern...\n"));
+                   if (svp && matcher_matches_sv(matcher, *svp)) {
+                       destroy_matcher(matcher);
+                       RETPUSHYES;
+                   }
                }
+               destroy_matcher(matcher);
+               RETPUSHNO;
            }
-           destroy_matcher(matcher);
-           RETPUSHNO;
        }
-       else if (SvIOK(Other) || SvNOK(Other)) {
+       else if (!SvOK(d)) {
+           /* undef ~~ array */
+           const I32 this_len = av_len(MUTABLE_AV(SvRV(e)));
            I32 i;
 
-           for(i = 0; i <= AvFILL((AV *) This); ++i) {
-               SV * const * const svp = av_fetch((AV *)This, i, FALSE);
-               if (!svp)
-                   continue;
-               
-               PUSHs(Other);
-               PUSHs(*svp);
-               PUTBACK;
-               if (CopHINTS_get(PL_curcop) & HINT_INTEGER)
-                   (void) pp_i_eq();
-               else
-                   (void) pp_eq();
-               SPAGAIN;
-               if (SvTRUEx(POPs))
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Undef-Array\n"));
+           for (i = 0; i <= this_len; ++i) {
+               SV * const * const svp = av_fetch(MUTABLE_AV(SvRV(e)), i, FALSE);
+               DEBUG_M(Perl_deb(aTHX_ "        testing for undef element...\n"));
+               if (!svp || !SvOK(*svp))
                    RETPUSHYES;
            }
            RETPUSHNO;
        }
-       else if (SvPOK(Other)) {
-           const I32 this_len = av_len((AV *) This);
-           I32 i;
+       else {
+         sm_any_array:
+           {
+               I32 i;
+               const I32 this_len = av_len(MUTABLE_AV(SvRV(e)));
 
-           for(i = 0; i <= this_len; ++i) {
-               SV * const * const svp = av_fetch((AV *)This, i, FALSE);
-               if (!svp)
-                   continue;
-               
-               PUSHs(Other);
-               PUSHs(*svp);
-               PUTBACK;
-               (void) pp_seq();
-               SPAGAIN;
-               if (SvTRUEx(POPs))
-                   RETPUSHYES;
+               DEBUG_M(Perl_deb(aTHX_ "    applying rule Any-Array\n"));
+               for (i = 0; i <= this_len; ++i) {
+                   SV * const * const svp = av_fetch(MUTABLE_AV(SvRV(e)), i, FALSE);
+                   if (!svp)
+                       continue;
+
+                   PUSHs(d);
+                   PUSHs(*svp);
+                   PUTBACK;
+                   /* infinite recursion isn't supposed to happen here */
+                   DEBUG_M(Perl_deb(aTHX_ "        recursively testing array element...\n"));
+                   (void) do_smartmatch(NULL, NULL);
+                   SPAGAIN;
+                   DEBUG_M(Perl_deb(aTHX_ "        recursion finished\n"));
+                   if (SvTRUEx(POPs))
+                       RETPUSHYES;
+               }
+               RETPUSHNO;
            }
-           RETPUSHNO;
        }
     }
-    else if (!SvOK(d) || !SvOK(e)) {
-       if (!SvOK(d) && !SvOK(e))
-           RETPUSHYES;
-       else
-           RETPUSHNO;
-    }
-    else if (SM_REGEX) {
-       PMOP * const matcher = make_matcher(this_regex);
+    /* ~~ qr// */
+    else if (SvROK(e) && SvTYPE(SvRV(e)) == SVt_REGEXP) {
+       if (!object_on_left && SvROK(d) && SvTYPE(SvRV(d)) == SVt_PVHV) {
+           SV *t = d; d = e; e = t;
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Hash-Regex\n"));
+           goto sm_regex_hash;
+       }
+       else if (!object_on_left && SvROK(d) && SvTYPE(SvRV(d)) == SVt_PVAV) {
+           SV *t = d; d = e; e = t;
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Array-Regex\n"));
+           goto sm_regex_array;
+       }
+       else {
+           PMOP * const matcher = make_matcher((REGEXP*) SvRV(e));
 
-       PUTBACK;
-       PUSHs(matcher_matches_sv(matcher, Other)
-           ? &PL_sv_yes
-           : &PL_sv_no);
-       destroy_matcher(matcher);
-       RETURN;
+           DEBUG_M(Perl_deb(aTHX_ "    applying rule Any-Regex\n"));
+           PUTBACK;
+           PUSHs(matcher_matches_sv(matcher, d)
+                   ? &PL_sv_yes
+                   : &PL_sv_no);
+           destroy_matcher(matcher);
+           RETURN;
+       }
     }
-    else if (SM_REF(PVCV)) {
-       I32 c;
-       /* This must be a null-prototyped sub, because we
-          already checked for the other kind. */
-       
-       ENTER;
-       SAVETMPS;
-       PUSHMARK(SP);
+    /* ~~ scalar */
+    /* See if there is overload magic on left */
+    else if (object_on_left && SvAMAGIC(d)) {
+       SV *tmpsv;
+       DEBUG_M(Perl_deb(aTHX_ "    applying rule Object-Any\n"));
+       DEBUG_M(Perl_deb(aTHX_ "        attempting overload\n"));
+       PUSHs(d); PUSHs(e);
        PUTBACK;
-       c = call_sv(This, G_SCALAR);
-       SPAGAIN;
-       if (c == 0)
-           PUSHs(&PL_sv_undef);
-       else if (SvTEMP(TOPs))
-           SvREFCNT_inc_void(TOPs);
-
-       if (SM_OTHER_REF(PVCV)) {
-           /* This one has to be null-proto'd too.
-              Call both of 'em, and compare the results */
-           PUSHMARK(SP);
-           c = call_sv(SvRV(Other), G_SCALAR);
+       tmpsv = amagic_call(d, e, smart_amg, AMGf_noright);
+       if (tmpsv) {
            SPAGAIN;
-           if (c == 0)
-               PUSHs(&PL_sv_undef);
-           else if (SvTEMP(TOPs))
-               SvREFCNT_inc_void(TOPs);
-           FREETMPS;
-           LEAVE;
-           PUTBACK;
-           return pp_eq();
+           (void)POPs;
+           SETs(tmpsv);
+           RETURN;
        }
-       
-       FREETMPS;
-       LEAVE;
-       RETURN;
+       SP -= 2;
+       DEBUG_M(Perl_deb(aTHX_ "        failed to run overload method; falling back...\n"));
+       goto sm_any_scalar;
     }
-    else if ( ((SvIOK(d) || SvNOK(d)) && (This = d) && (Other = e))
-         ||   ((SvIOK(e) || SvNOK(e)) && (This = e) && (Other = d)) )
-    {
-       if (SvPOK(Other) && !looks_like_number(Other)) {
-           /* String comparison */
-           PUSHs(d); PUSHs(e);
-           PUTBACK;
-           return pp_seq();
-       }
-       /* Otherwise, numeric comparison */
+    else if (!SvOK(d)) {
+       /* undef ~~ scalar ; we already know that the scalar is SvOK */
+       DEBUG_M(Perl_deb(aTHX_ "    applying rule undef-Any\n"));
+       RETPUSHNO;
+    }
+    else
+  sm_any_scalar:
+    if (SvNIOK(e) || (SvPOK(e) && looks_like_number(e) && SvNIOK(d))) {
+       DEBUG_M(if (SvNIOK(e))
+                   Perl_deb(aTHX_ "    applying rule Any-Num\n");
+               else
+                   Perl_deb(aTHX_ "    applying rule Num-numish\n");
+       );
+       /* numeric comparison */
        PUSHs(d); PUSHs(e);
        PUTBACK;
        if (CopHINTS_get(PL_curcop) & HINT_INTEGER)
@@ -4265,6 +4459,7 @@ S_do_smartmatch(pTHX_ HV *seen_this, HV *seen_other)
     }
     
     /* As a last resort, use string comparison */
+    DEBUG_M(Perl_deb(aTHX_ "    applying rule Any-Any\n"));
     PUSHs(d); PUSHs(e);
     PUTBACK;
     return pp_seq();
@@ -4387,6 +4582,8 @@ S_doparseform(pTHX_ SV *sv)
     bool unchopnum = FALSE;
     int maxops = 12; /* FF_LINEMARK + FF_END + 10 (\0 without preceding \n) */
 
+    PERL_ARGS_ASSERT_DOPARSEFORM;
+
     if (len == 0)
        Perl_croak(aTHX_ "Null picture in formline");
 
@@ -4619,8 +4816,8 @@ S_run_user_filter(pTHX_ int idx, SV *buf_sv, int maxlen)
     dVAR;
     SV * const datasv = FILTER_DATA(idx);
     const int filter_has_file = IoLINES(datasv);
-    SV * const filter_state = (SV *)IoTOP_GV(datasv);
-    SV * const filter_sub = (SV *)IoBOTTOM_GV(datasv);
+    SV * const filter_state = MUTABLE_SV(IoTOP_GV(datasv));
+    SV * const filter_sub = MUTABLE_SV(IoBOTTOM_GV(datasv));
     int status = 0;
     SV *upstream;
     STRLEN got_len;
@@ -4629,6 +4826,8 @@ S_run_user_filter(pTHX_ int idx, SV *buf_sv, int maxlen)
     bool read_from_cache = FALSE;
     STRLEN umaxlen;
 
+    PERL_ARGS_ASSERT_RUN_USER_FILTER;
+
     assert(maxlen >= 0);
     umaxlen = maxlen;
 
@@ -4638,7 +4837,7 @@ S_run_user_filter(pTHX_ int idx, SV *buf_sv, int maxlen)
        not sure where the trouble is yet.  XXX */
 
     if (IoFMT_GV(datasv)) {
-       SV *const cache = (SV *)IoFMT_GV(datasv);
+       SV *const cache = MUTABLE_SV(IoFMT_GV(datasv));
        if (SvOK(cache)) {
            STRLEN cache_len;
            const char *cache_p = SvPV(cache, cache_len);
@@ -4697,7 +4896,7 @@ S_run_user_filter(pTHX_ int idx, SV *buf_sv, int maxlen)
        SAVETMPS;
        EXTEND(SP, 2);
 
-       DEFSV = upstream;
+       DEFSV_set(upstream);
        PUSHMARK(SP);
        mPUSHi(0);
        if (filter_state) {
@@ -4737,10 +4936,10 @@ S_run_user_filter(pTHX_ int idx, SV *buf_sv, int maxlen)
     if (prune_from) {
        /* Oh. Too long. Stuff some in our cache.  */
        STRLEN cached_len = got_p + got_len - prune_from;
-       SV *cache = (SV *)IoFMT_GV(datasv);
+       SV *cache = MUTABLE_SV(IoFMT_GV(datasv));
 
        if (!cache) {
-           IoFMT_GV(datasv) = (GV*) (cache = newSV(got_len - umaxlen));
+           IoFMT_GV(datasv) = MUTABLE_GV((cache = newSV(got_len - umaxlen)));
        } else if (SvOK(cache)) {
            /* Cache should be empty.  */
            assert(!SvCUR(cache));
@@ -4795,9 +4994,15 @@ S_run_user_filter(pTHX_ int idx, SV *buf_sv, int maxlen)
 static bool
 S_path_is_absolute(const char *name)
 {
+    PERL_ARGS_ASSERT_PATH_IS_ABSOLUTE;
+
     if (PERL_FILE_IS_ABSOLUTE(name)
-#ifdef MACOS_TRADITIONAL
-       || (*name == ':')
+#ifdef WIN32
+       || (*name == '.' && ((name[1] == '/' ||
+                            (name[1] == '.' && name[2] == '/'))
+                        || (name[1] == '\\' ||
+                            ( name[1] == '.' && name[2] == '\\')))
+           )
 #else
        || (*name == '.' && (name[1] == '/' ||
                             (name[1] == '.' && name[2] == '/')))