Add a new SMAGIC flag, to signal a call to SvSETMAGIC. Add it to
[p5sagit/p5-mst-13.2.git] / pp_ctl.c
index d461873..fd1bccd 100644 (file)
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -1,6 +1,7 @@
 /*    pp_ctl.c
  *
- *    Copyright (c) 1991-2002, Larry Wall
+ *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
+ *    2000, 2001, 2002, 2003, 2004, 2005, 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.
  * And whither then?  I cannot say.
  */
 
+/* This file contains control-oriented pp ("push/pop") functions that
+ * execute the opcodes that make up a perl program. A typical pp function
+ * expects to find its arguments on the stack, and usually pushes its
+ * results onto the stack, hence the 'pp' terminology. Each OP structure
+ * contains a pointer to the relevant pp_foo() function.
+ *
+ * Control-oriented means things like pp_enteriter() and pp_next(), which
+ * alter the flow of control of the program.
+ */
+
+
 #include "EXTERN.h"
 #define PERL_IN_PP_CTL_C
 #include "perl.h"
 
 #ifndef WORD_ALIGN
-#define WORD_ALIGN sizeof(U16)
+#define WORD_ALIGN sizeof(U32)
 #endif
 
 #define DOCATCH(o) ((CATCH_GET == TRUE) ? docatch(o) : (o))
@@ -58,6 +70,7 @@ PP(pp_regcreset)
     /* XXXX Should store the old value to allow for tie/overload - and
        restore in regcomp, where marked with XXXX. */
     PL_reginterp_cnt = 0;
+    TAINT_NOT;
     return NORMAL;
 }
 
@@ -65,18 +78,43 @@ PP(pp_regcomp)
 {
     dSP;
     register PMOP *pm = (PMOP*)cLOGOP->op_other;
-    register char *t;
     SV *tmpstr;
-    STRLEN len;
     MAGIC *mg = Null(MAGIC*);
-    
-    tmpstr = POPs;
 
     /* prevent recompiling under /o and ithreads. */
-#if defined(USE_ITHREADS) || defined(USE_5005THREADS)
-    if (pm->op_pmflags & PMf_KEEP && PM_GETRE(pm))
-        RETURN;
+#if defined(USE_ITHREADS)
+    if (pm->op_pmflags & PMf_KEEP && PM_GETRE(pm)) {
+       if (PL_op->op_flags & OPf_STACKED) {
+           dMARK;
+           SP = MARK;
+       }
+       else
+           (void)POPs;
+       RETURN;
+    }
 #endif
+    if (PL_op->op_flags & OPf_STACKED) {
+       /* multiple args; concatentate them */
+       dMARK; dORIGMARK;
+       tmpstr = PAD_SV(ARGTARG);
+       sv_setpvn(tmpstr, "", 0);
+       while (++MARK <= SP) {
+           if (PL_amagic_generation) {
+               SV *sv;
+               if ((SvAMAGIC(tmpstr) || SvAMAGIC(*MARK)) &&
+                   (sv = amagic_call(tmpstr, *MARK, concat_amg, AMGf_assign)))
+               {
+                  sv_setsv(tmpstr, sv);
+                  continue;
+               }
+           }
+           sv_catsv(tmpstr, *MARK);
+       }
+       SvSETMAGIC(tmpstr);
+       SP = ORIGMARK;
+    }
+    else
+       tmpstr = POPs;
 
     if (SvROK(tmpstr)) {
        SV *sv = SvRV(tmpstr);
@@ -84,12 +122,13 @@ PP(pp_regcomp)
            mg = mg_find(sv, PERL_MAGIC_qr);
     }
     if (mg) {
-       regexp *re = (regexp *)mg->mg_obj;
+       regexp * const re = (regexp *)mg->mg_obj;
        ReREFCNT_dec(PM_GETRE(pm));
        PM_SETRE(pm, ReREFCNT_inc(re));
     }
     else {
-       t = SvPV(tmpstr, len);
+       STRLEN len;
+       const char *t = SvPV_const(tmpstr, len);
 
        /* Check against the last compiled regexp. */
        if (!PM_GETRE(pm) || !PM_GETRE(pm)->precomp ||
@@ -97,7 +136,7 @@ PP(pp_regcomp)
            memNE(PM_GETRE(pm)->precomp, t, len))
        {
            if (PM_GETRE(pm)) {
-               ReREFCNT_dec(PM_GETRE(pm));
+               ReREFCNT_dec(PM_GETRE(pm));
                PM_SETRE(pm, Null(REGEXP*));    /* crucial if regcomp aborts */
            }
            if (PL_op->op_flags & OPf_SPECIAL)
@@ -111,7 +150,7 @@ PP(pp_regcomp)
                if (pm->op_pmdynflags & PMdf_UTF8)
                    t = (char*)bytes_to_utf8((U8*)t, &len);
            }
-           PM_SETRE(pm, CALLREGCOMP(aTHX_ t, t + len, pm));
+           PM_SETRE(pm, CALLREGCOMP(aTHX_ (char *)t, (char *)t + len, pm));
            if (!DO_UTF8(tmpstr) && (pm->op_pmdynflags & PMdf_UTF8))
                Safefree(t);
            PL_reginterp_cnt = 0;       /* XXXX Be extra paranoid - needed
@@ -138,7 +177,7 @@ PP(pp_regcomp)
     /* XXX runtime compiled output needs to move to the pad */
     if (pm->op_pmflags & PMf_KEEP) {
        pm->op_private &= ~OPpRUNTIME;  /* no point compiling again */
-#if !defined(USE_ITHREADS) && !defined(USE_5005THREADS)
+#if !defined(USE_ITHREADS)
        /* XXX can't change the optree at runtime either */
        cLOGOP->op_first->op_next = PL_op->op_next;
 #endif
@@ -149,19 +188,26 @@ PP(pp_regcomp)
 PP(pp_substcont)
 {
     dSP;
-    register PMOP *pm = (PMOP*) cLOGOP->op_other;
     register PERL_CONTEXT *cx = &cxstack[cxstack_ix];
-    register SV *dstr = cx->sb_dstr;
+    register PMOP * const pm = (PMOP*) cLOGOP->op_other;
+    register SV * const dstr = cx->sb_dstr;
     register char *s = cx->sb_s;
     register char *m = cx->sb_m;
     char *orig = cx->sb_orig;
-    register REGEXP *rx = cx->sb_rx;
+    register REGEXP * const rx = cx->sb_rx;
+    SV *nsv = Nullsv;
+    REGEXP *old = PM_GETRE(pm);
+    if(old != rx) {
+       if(old)
+           ReREFCNT_dec(old);
+       PM_SETRE(pm,rx);
+    }
 
     rxres_restore(&cx->sb_rxres, rx);
-    PL_reg_match_utf8 = SvUTF8(cx->sb_targ) ? 1 : 0;
+    RX_MATCH_UTF8_set(rx, DO_UTF8(cx->sb_targ));
 
     if (cx->sb_iters++) {
-       I32 saviters = cx->sb_iters;
+       const I32 saviters = cx->sb_iters;
        if (cx->sb_iters > cx->sb_maxiters)
            DIE(aTHX_ "Substitution loop");
 
@@ -176,23 +222,35 @@ PP(pp_substcont)
                                      ? (REXEC_IGNOREPOS|REXEC_NOT_FIRST)
                                      : (REXEC_COPY_STR|REXEC_IGNOREPOS|REXEC_NOT_FIRST))))
        {
-           SV *targ = cx->sb_targ;
+           SV * const targ = cx->sb_targ;
 
-           sv_catpvn(dstr, s, cx->sb_strend - s);
+           assert(cx->sb_strend >= s);
+           if(cx->sb_strend > s) {
+                if (DO_UTF8(dstr) && !SvUTF8(targ))
+                     sv_catpvn_utf8_upgrade(dstr, s, cx->sb_strend - s, nsv);
+                else
+                     sv_catpvn(dstr, s, cx->sb_strend - s);
+           }
            cx->sb_rxtainted |= RX_MATCH_TAINTED(rx);
 
-           (void)SvOOK_off(targ);
-           Safefree(SvPVX(targ));
-           SvPVX(targ) = SvPVX(dstr);
+#ifdef PERL_OLD_COPY_ON_WRITE
+           if (SvIsCOW(targ)) {
+               sv_force_normal_flags(targ, SV_COW_DROP_PV);
+           } else
+#endif
+           {
+               SvPV_free(targ);
+           }
+           SvPV_set(targ, SvPVX(dstr));
            SvCUR_set(targ, SvCUR(dstr));
            SvLEN_set(targ, SvLEN(dstr));
            if (DO_UTF8(dstr))
                SvUTF8_on(targ);
-           SvPVX(dstr) = 0;
+           SvPV_set(dstr, (char*)0);
            sv_free(dstr);
 
            TAINT_IF(cx->sb_rxtainted & 1);
-           PUSHs(sv_2mortal(newSViv((I32)cx->sb_iters - 1)));
+           PUSHs(sv_2mortal(newSViv(saviters - 1)));
 
            (void)SvPOK_only_UTF8(targ);
            TAINT_IF(cx->sb_rxtainted);
@@ -200,6 +258,7 @@ PP(pp_substcont)
            SvTAINT(targ);
 
            LEAVE_SCOPE(cx->sb_oldsave);
+           ReREFCNT_dec(rx);
            POPSUBST(cx);
            RETURNOP(pm->op_next);
        }
@@ -213,15 +272,19 @@ PP(pp_substcont)
        cx->sb_strend = s + (cx->sb_strend - m);
     }
     cx->sb_m = m = rx->startp[0] + orig;
-    if (m > s)
-       sv_catpvn(dstr, s, m-s);
+    if (m > s) {
+       if (DO_UTF8(dstr) && !SvUTF8(cx->sb_targ))
+           sv_catpvn_utf8_upgrade(dstr, s, m - s, nsv);
+       else
+           sv_catpvn(dstr, s, m-s);
+    }
     cx->sb_s = rx->endp[0] + orig;
     { /* Update the pos() information. */
-       SV *sv = cx->sb_targ;
+       SV * const sv = cx->sb_targ;
        MAGIC *mg;
        I32 i;
        if (SvTYPE(sv) < SVt_PVMG)
-           (void)SvUPGRADE(sv, SVt_PVMG);
+           SvUPGRADE(sv, SVt_PVMG);
        if (!(mg = mg_find(sv, PERL_MAGIC_regex_global))) {
            sv_magic(sv, Nullsv, PERL_MAGIC_regex_global, Nullch, 0);
            mg = mg_find(sv, PERL_MAGIC_regex_global);
@@ -231,6 +294,8 @@ PP(pp_substcont)
            sv_pos_b2u(sv, &i);
        mg->mg_len = i;
     }
+    if (old != rx)
+       (void)ReREFCNT_inc(rx);
     cx->sb_rxtainted |= RX_MATCH_TAINTED(rx);
     rxres_save(&cx->sb_rxres, rx);
     RETURNOP(pm->op_pmreplstart);
@@ -243,9 +308,13 @@ Perl_rxres_save(pTHX_ void **rsp, REGEXP *rx)
     U32 i;
 
     if (!p || p[1] < rx->nparens) {
+#ifdef PERL_OLD_COPY_ON_WRITE
+       i = 7 + rx->nparens * 2;
+#else
        i = 6 + rx->nparens * 2;
+#endif
        if (!p)
-           New(501, p, i, UV);
+           Newx(p, i, UV);
        else
            Renew(p, i, UV);
        *rsp = (void*)p;
@@ -254,6 +323,11 @@ Perl_rxres_save(pTHX_ void **rsp, REGEXP *rx)
     *p++ = PTR2UV(RX_MATCH_COPIED(rx) ? rx->subbeg : Nullch);
     RX_MATCH_COPIED_off(rx);
 
+#ifdef PERL_OLD_COPY_ON_WRITE
+    *p++ = PTR2UV(rx->saved_copy);
+    rx->saved_copy = Nullsv;
+#endif
+
     *p++ = rx->nparens;
 
     *p++ = PTR2UV(rx->subbeg);
@@ -270,11 +344,17 @@ Perl_rxres_restore(pTHX_ void **rsp, REGEXP *rx)
     UV *p = (UV*)*rsp;
     U32 i;
 
-    if (RX_MATCH_COPIED(rx))
-       Safefree(rx->subbeg);
+    RX_MATCH_COPY_FREE(rx);
     RX_MATCH_COPIED_set(rx, *p);
     *p++ = 0;
 
+#ifdef PERL_OLD_COPY_ON_WRITE
+    if (rx->saved_copy)
+       SvREFCNT_dec (rx->saved_copy);
+    rx->saved_copy = INT2PTR(SV*,*p);
+    *p++ = 0;
+#endif
+
     rx->nparens = *p++;
 
     rx->subbeg = INT2PTR(char*,*p++);
@@ -288,10 +368,22 @@ Perl_rxres_restore(pTHX_ void **rsp, REGEXP *rx)
 void
 Perl_rxres_free(pTHX_ void **rsp)
 {
-    UV *p = (UV*)*rsp;
+    UV * const p = (UV*)*rsp;
 
     if (p) {
+#ifdef PERL_POISON
+       void *tmp = INT2PTR(char*,*p);
+       Safefree(tmp);
+       if (*p)
+           Poison(*p, 1, sizeof(*p));
+#else
        Safefree(INT2PTR(char*,*p));
+#endif
+#ifdef PERL_OLD_COPY_ON_WRITE
+       if (p[1]) {
+           SvREFCNT_dec (INT2PTR(SV*,p[1]));
+       }
+#endif
        Safefree(p);
        *rsp = Null(void*);
     }
@@ -300,49 +392,54 @@ Perl_rxres_free(pTHX_ void **rsp)
 PP(pp_formline)
 {
     dSP; dMARK; dORIGMARK;
-    register SV *tmpForm = *++MARK;
-    register U16 *fpc;
+    register SV * const tmpForm = *++MARK;
+    register U32 *fpc;
     register char *t;
-    register char *f;
-    register char *s;
-    register char *send;
+    const char *f;
     register I32 arg;
     register SV *sv = Nullsv;
-    char *item = Nullch;
+    const char *item = Nullch;
     I32 itemsize  = 0;
     I32 fieldsize = 0;
     I32 lines = 0;
     bool chopspace = (strchr(PL_chopset, ' ') != Nullch);
-    char *chophere = Nullch;
+    const char *chophere = Nullch;
     char *linemark = Nullch;
     NV value;
     bool gotsome = FALSE;
     STRLEN len;
-    STRLEN fudge = SvCUR(tmpForm) * (IN_BYTES ? 1 : 3) + 1;
-    bool item_is_utf = FALSE;
+    const STRLEN fudge = SvPOK(tmpForm)
+                       ? (SvCUR(tmpForm) * (IN_BYTES ? 1 : 3) + 1) : 0;
+    bool item_is_utf8 = FALSE;
+    bool targ_is_utf8 = FALSE;
+    SV * nsv = Nullsv;
+    OP * parseres = 0;
+    const char *fmt;
+    bool oneline;
 
     if (!SvMAGICAL(tmpForm) || !SvCOMPILED(tmpForm)) {
        if (SvREADONLY(tmpForm)) {
            SvREADONLY_off(tmpForm);
-           doparseform(tmpForm);
+           parseres = doparseform(tmpForm);
            SvREADONLY_on(tmpForm);
        }
        else
-           doparseform(tmpForm);
+           parseres = doparseform(tmpForm);
+       if (parseres)
+           return parseres;
     }
-
     SvPV_force(PL_formtarget, len);
+    if (DO_UTF8(PL_formtarget))
+       targ_is_utf8 = TRUE;
     t = SvGROW(PL_formtarget, len + fudge + 1);  /* XXX SvCUR bad */
     t += len;
-    f = SvPV(tmpForm, len);
+    f = SvPV_const(tmpForm, len);
     /* need to jump to the next word */
-    s = f + len + WORD_ALIGN - SvCUR(tmpForm) % WORD_ALIGN;
-
-    fpc = (U16*)s;
+    fpc = (U32*)(f + len + WORD_ALIGN - SvCUR(tmpForm) % WORD_ALIGN);
 
     for (;;) {
        DEBUG_f( {
-           char *name = "???";
+           const char *name = "???";
            arg = -1;
            switch (*fpc) {
            case FF_LITERAL:    arg = fpc[1]; name = "LITERAL"; break;
@@ -362,7 +459,8 @@ PP(pp_formline)
            case FF_MORE:       name = "MORE";          break;
            case FF_LINEMARK:   name = "LINEMARK";      break;
            case FF_END:        name = "END";           break;
-            case FF_0DECIMAL:  name = "0DECIMAL";      break;
+           case FF_0DECIMAL:   name = "0DECIMAL";      break;
+           case FF_LINESNGL:   name = "LINESNGL";      break;
            }
            if (arg >= 0)
                PerlIO_printf(Perl_debug_log, "%-16s%ld\n", name, (long) arg);
@@ -378,6 +476,21 @@ PP(pp_formline)
 
        case FF_LITERAL:
            arg = *fpc++;
+           if (targ_is_utf8 && !SvUTF8(tmpForm)) {
+               SvCUR_set(PL_formtarget, t - SvPVX_const(PL_formtarget));
+               *t = '\0';
+               sv_catpvn_utf8_upgrade(PL_formtarget, f, arg, nsv);
+               t = SvEND(PL_formtarget);
+               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);
+               t = SvEND(PL_formtarget);
+               targ_is_utf8 = TRUE;
+           }
            while (arg--)
                *t++ = *f++;
            break;
@@ -401,125 +514,134 @@ PP(pp_formline)
            break;
 
        case FF_CHECKNL:
-           item = s = SvPV(sv, len);
-           itemsize = len;
-           if (DO_UTF8(sv)) {
-               itemsize = sv_len_utf8(sv);
-               if (itemsize != (I32)len) {
-                   I32 itembytes;
-                   if (itemsize > fieldsize) {
-                       itemsize = fieldsize;
-                       itembytes = itemsize;
-                       sv_pos_u2b(sv, &itembytes, 0);
-                   }
-                   else
-                       itembytes = len;
-                   send = chophere = s + itembytes;
-                   while (s < send) {
-                       if (*s & ~31)
-                           gotsome = TRUE;
-                       else if (*s == '\n')
-                           break;
-                       s++;
+           {
+               const char *send;
+               const char *s = item = SvPV_const(sv, len);
+               itemsize = len;
+               if (DO_UTF8(sv)) {
+                   itemsize = sv_len_utf8(sv);
+                   if (itemsize != (I32)len) {
+                       I32 itembytes;
+                       if (itemsize > fieldsize) {
+                           itemsize = fieldsize;
+                           itembytes = itemsize;
+                           sv_pos_u2b(sv, &itembytes, 0);
+                       }
+                       else
+                           itembytes = len;
+                       send = chophere = s + itembytes;
+                       while (s < send) {
+                           if (*s & ~31)
+                               gotsome = TRUE;
+                           else if (*s == '\n')
+                               break;
+                           s++;
+                       }
+                       item_is_utf8 = TRUE;
+                       itemsize = s - item;
+                       sv_pos_b2u(sv, &itemsize);
+                       break;
                    }
-                   item_is_utf = TRUE;
-                   itemsize = s - item;
-                   sv_pos_b2u(sv, &itemsize);
-                   break;
                }
+               item_is_utf8 = FALSE;
+               if (itemsize > fieldsize)
+                   itemsize = fieldsize;
+               send = chophere = s + itemsize;
+               while (s < send) {
+                   if (*s & ~31)
+                       gotsome = TRUE;
+                   else if (*s == '\n')
+                       break;
+                   s++;
+               }
+               itemsize = s - item;
+               break;
            }
-           item_is_utf = FALSE;
-           if (itemsize > fieldsize)
-               itemsize = fieldsize;
-           send = chophere = s + itemsize;
-           while (s < send) {
-               if (*s & ~31)
-                   gotsome = TRUE;
-               else if (*s == '\n')
-                   break;
-               s++;
-           }
-           itemsize = s - item;
-           break;
 
        case FF_CHECKCHOP:
-           item = s = SvPV(sv, len);
-           itemsize = len;
-           if (DO_UTF8(sv)) {
-               itemsize = sv_len_utf8(sv);
-               if (itemsize != (I32)len) {
-                   I32 itembytes;
-                   if (itemsize <= fieldsize) {
-                       send = chophere = s + itemsize;
-                       while (s < send) {
-                           if (*s == '\r') {
-                               itemsize = s - item;
-                               break;
-                           }
-                           if (*s++ & ~31)
-                               gotsome = TRUE;
-                       }
-                   }
-                   else {
-                       itemsize = fieldsize;
-                       itembytes = itemsize;
-                       sv_pos_u2b(sv, &itembytes, 0);
-                       send = chophere = s + itembytes;
-                       while (s < send || (s == send && isSPACE(*s))) {
-                           if (isSPACE(*s)) {
-                               if (chopspace)
+           {
+               const char *s = item = SvPV_const(sv, len);
+               itemsize = len;
+               if (DO_UTF8(sv)) {
+                   itemsize = sv_len_utf8(sv);
+                   if (itemsize != (I32)len) {
+                       I32 itembytes;
+                       if (itemsize <= fieldsize) {
+                           const char *send = chophere = s + itemsize;
+                           while (s < send) {
+                               if (*s == '\r') {
+                                   itemsize = s - item;
                                    chophere = s;
-                               if (*s == '\r')
                                    break;
-                           }
-                           else {
-                               if (*s & ~31)
+                               }
+                               if (*s++ & ~31)
                                    gotsome = TRUE;
-                               if (strchr(PL_chopset, *s))
-                                   chophere = s + 1;
                            }
-                           s++;
                        }
-                       itemsize = chophere - item;
-                       sv_pos_b2u(sv, &itemsize);
-                   }
-                   item_is_utf = TRUE;
-                   break;
-               }
-           }
-           item_is_utf = FALSE;
-           if (itemsize <= fieldsize) {
-               send = chophere = s + itemsize;
-               while (s < send) {
-                   if (*s == '\r') {
-                       itemsize = s - item;
+                       else {
+                           const char *send;
+                           itemsize = fieldsize;
+                           itembytes = itemsize;
+                           sv_pos_u2b(sv, &itembytes, 0);
+                           send = chophere = s + itembytes;
+                           while (s < send || (s == send && isSPACE(*s))) {
+                               if (isSPACE(*s)) {
+                                   if (chopspace)
+                                       chophere = s;
+                                   if (*s == '\r')
+                                       break;
+                               }
+                               else {
+                                   if (*s & ~31)
+                                       gotsome = TRUE;
+                                   if (strchr(PL_chopset, *s))
+                                       chophere = s + 1;
+                               }
+                               s++;
+                           }
+                           itemsize = chophere - item;
+                           sv_pos_b2u(sv, &itemsize);
+                       }
+                       item_is_utf8 = TRUE;
                        break;
                    }
-                   if (*s++ & ~31)
-                       gotsome = TRUE;
                }
-           }
-           else {
-               itemsize = fieldsize;
-               send = chophere = s + itemsize;
-               while (s < send || (s == send && isSPACE(*s))) {
-                   if (isSPACE(*s)) {
-                       if (chopspace)
+               item_is_utf8 = FALSE;
+               if (itemsize <= fieldsize) {
+                   const char *const send = chophere = s + itemsize;
+                   while (s < send) {
+                       if (*s == '\r') {
+                           itemsize = s - item;
                            chophere = s;
-                       if (*s == '\r')
                            break;
-                   }
-                   else {
-                       if (*s & ~31)
+                       }
+                       if (*s++ & ~31)
                            gotsome = TRUE;
-                       if (strchr(PL_chopset, *s))
-                           chophere = s + 1;
                    }
-                   s++;
                }
-               itemsize = chophere - item;
+               else {
+                   const char *send;
+                   itemsize = fieldsize;
+                   send = chophere = s + itemsize;
+                   while (s < send || (s == send && isSPACE(*s))) {
+                       if (isSPACE(*s)) {
+                           if (chopspace)
+                               chophere = s;
+                           if (*s == '\r')
+                               break;
+                       }
+                       else {
+                           if (*s & ~31)
+                               gotsome = TRUE;
+                           if (strchr(PL_chopset, *s))
+                               chophere = s + 1;
+                       }
+                       s++;
+                   }
+                   itemsize = chophere - item;
+               }
+               break;
            }
-           break;
 
        case FF_SPACE:
            arg = fieldsize - itemsize;
@@ -541,116 +663,151 @@ PP(pp_formline)
            break;
 
        case FF_ITEM:
-           arg = itemsize;
-           s = item;
-           if (item_is_utf) {
-               while (arg--) {
-                   if (UTF8_IS_CONTINUED(*s)) {
-                       STRLEN skip = UTF8SKIP(s);
-                       switch (skip) {
-                       default:
-                           Move(s,t,skip,char);
-                           s += skip;
-                           t += skip;
-                           break;
-                       case 7: *t++ = *s++;
-                       case 6: *t++ = *s++;
-                       case 5: *t++ = *s++;
-                       case 4: *t++ = *s++;
-                       case 3: *t++ = *s++;
-                       case 2: *t++ = *s++;
-                       case 1: *t++ = *s++;
+           {
+               const char *s = item;
+               arg = itemsize;
+               if (item_is_utf8) {
+                   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);
+                       t = SvEND(PL_formtarget);
+                       targ_is_utf8 = TRUE;
+                   }
+                   while (arg--) {
+                       if (UTF8_IS_CONTINUED(*s)) {
+                           STRLEN skip = UTF8SKIP(s);
+                           switch (skip) {
+                           default:
+                               Move(s,t,skip,char);
+                               s += skip;
+                               t += skip;
+                               break;
+                           case 7: *t++ = *s++;
+                           case 6: *t++ = *s++;
+                           case 5: *t++ = *s++;
+                           case 4: *t++ = *s++;
+                           case 3: *t++ = *s++;
+                           case 2: *t++ = *s++;
+                           case 1: *t++ = *s++;
+                           }
+                       }
+                       else {
+                           if ( !((*t++ = *s++) & ~31) )
+                               t[-1] = ' ';
                        }
                    }
-                   else {
-                       if ( !((*t++ = *s++) & ~31) )
-                           t[-1] = ' ';
+                   break;
+               }
+               if (targ_is_utf8 && !item_is_utf8) {
+                   SvCUR_set(PL_formtarget, t - SvPVX_const(PL_formtarget));
+                   *t = '\0';
+                   sv_catpvn_utf8_upgrade(PL_formtarget, s, arg, nsv);
+                   for (; t < SvEND(PL_formtarget); t++) {
+#ifdef EBCDIC
+                       const int ch = *t;
+                       if (iscntrl(ch))
+#else
+                           if (!(*t & ~31))
+#endif
+                               *t = ' ';
                    }
+                   break;
                }
-               break;
-           }
-           while (arg--) {
+               while (arg--) {
 #ifdef EBCDIC
-               int ch = *t++ = *s++;
-               if (iscntrl(ch))
+                   const int ch = *t++ = *s++;
+                   if (iscntrl(ch))
 #else
-               if ( !((*t++ = *s++) & ~31) )
+                       if ( !((*t++ = *s++) & ~31) )
 #endif
-                   t[-1] = ' ';
+                           t[-1] = ' ';
+               }
+               break;
            }
-           break;
 
        case FF_CHOP:
-           s = chophere;
-           if (chopspace) {
-               while (*s && isSPACE(*s))
-                   s++;
+           {
+               const char *s = chophere;
+               if (chopspace) {
+                   while (*s && isSPACE(*s))
+                       s++;
+               }
+               sv_chop(sv,s);
+               SvSETMAGIC(sv);
+               break;
            }
-           sv_chop(sv,s);
-           break;
 
+       case FF_LINESNGL:
+           chopspace = 0;
+           oneline = TRUE;
+           goto ff_line;
        case FF_LINEGLOB:
-           item = s = SvPV(sv, len);
-           itemsize = len;
-           item_is_utf = FALSE;                /* XXX is this correct? */
-           if (itemsize) {
-               gotsome = TRUE;
-               send = s + itemsize;
-               while (s < send) {
-                   if (*s++ == '\n') {
-                       if (s == send)
-                           itemsize--;
-                       else
-                           lines++;
+           oneline = FALSE;
+       ff_line:
+           {
+               const char *s = item = SvPV_const(sv, len);
+               itemsize = len;
+               if ((item_is_utf8 = DO_UTF8(sv)))
+                   itemsize = sv_len_utf8(sv);
+               if (itemsize) {
+                   bool chopped = FALSE;
+                   const char *const send = s + len;
+                   gotsome = TRUE;
+                   chophere = s + itemsize;
+                   while (s < send) {
+                       if (*s++ == '\n') {
+                           if (oneline) {
+                               chopped = TRUE;
+                               chophere = s;
+                               break;
+                           } else {
+                               if (s == send) {
+                                   itemsize--;
+                                   chopped = TRUE;
+                               } 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);
+                   t = SvPVX(PL_formtarget) + SvCUR(PL_formtarget);
+                   if (item_is_utf8)
+                       targ_is_utf8 = TRUE;
                }
-               SvCUR_set(PL_formtarget, t - SvPVX(PL_formtarget));
-               sv_catpvn(PL_formtarget, item, itemsize);
-               SvGROW(PL_formtarget, SvCUR(PL_formtarget) + fudge + 1);
-               t = SvPVX(PL_formtarget) + SvCUR(PL_formtarget);
+               break;
            }
-           break;
 
+       case FF_0DECIMAL:
+           arg = *fpc++;
+#if defined(USE_LONG_DOUBLE)
+           fmt = (arg & 256) ? "%#0*.*" PERL_PRIfldbl : "%0*.*" PERL_PRIfldbl;
+#else
+           fmt = (arg & 256) ? "%#0*.*f"              : "%0*.*f";
+#endif
+           goto ff_dec;
        case FF_DECIMAL:
-           /* If the field is marked with ^ and the value is undefined,
-              blank it out. */
            arg = *fpc++;
-           if ((arg & 512) && !SvOK(sv)) {
-               arg = fieldsize;
-               while (arg--)
-                   *t++ = ' ';
-               break;
-           }
-           gotsome = TRUE;
-           value = SvNV(sv);
-           /* Formats aren't yet marked for locales, so assume "yes". */
-           {
-               STORE_NUMERIC_STANDARD_SET_LOCAL();
 #if defined(USE_LONG_DOUBLE)
-               if (arg & 256) {
-                   sprintf(t, "%#*.*" PERL_PRIfldbl,
-                           (int) fieldsize, (int) arg & 255, value);
-               } else {
-                   sprintf(t, "%*.0" PERL_PRIfldbl, (int) fieldsize, value);
-               }
+           fmt = (arg & 256) ? "%#*.*" PERL_PRIfldbl : "%*.*" PERL_PRIfldbl;
 #else
-               if (arg & 256) {
-                   sprintf(t, "%#*.*f",
-                           (int) fieldsize, (int) arg & 255, value);
-               } else {
-                   sprintf(t, "%*.0f",
-                           (int) fieldsize, value);
-               }
+            fmt = (arg & 256) ? "%#*.*f"              : "%*.*f";
 #endif
-               RESTORE_NUMERIC_STANDARD();
-           }
-           t += fieldsize;
-           break;
-
-       case FF_0DECIMAL:
+       ff_dec:
            /* If the field is marked with ^ and the value is undefined,
               blank it out. */
-           arg = *fpc++;
            if ((arg & 512) && !SvOK(sv)) {
                arg = fieldsize;
                while (arg--)
@@ -659,31 +816,22 @@ PP(pp_formline)
            }
            gotsome = TRUE;
            value = SvNV(sv);
+           /* overflow evidence */
+           if (num_overflow(value, fieldsize, arg)) {
+               arg = fieldsize;
+               while (arg--)
+                   *t++ = '#';
+               break;
+           }
            /* Formats aren't yet marked for locales, so assume "yes". */
            {
                STORE_NUMERIC_STANDARD_SET_LOCAL();
-#if defined(USE_LONG_DOUBLE)
-               if (arg & 256) {
-                   sprintf(t, "%#0*.*" PERL_PRIfldbl,
-                           (int) fieldsize, (int) arg & 255, value);
-/* is this legal? I don't have long doubles */
-               } else {
-                   sprintf(t, "%0*.0" PERL_PRIfldbl, (int) fieldsize, value);
-               }
-#else
-               if (arg & 256) {
-                   sprintf(t, "%#0*.*f",
-                           (int) fieldsize, (int) arg & 255, value);
-               } else {
-                   sprintf(t, "%0*.0f",
-                           (int) fieldsize, value);
-               }
-#endif
+               sprintf(t, fmt, (int) fieldsize, (int) arg & 255, value);
                RESTORE_NUMERIC_STANDARD();
            }
            t += fieldsize;
            break;
-       
+
        case FF_NEWLINE:
            f++;
            while (t-- > linemark && *t == ' ') ;
@@ -696,13 +844,15 @@ PP(pp_formline)
            if (gotsome) {
                if (arg) {              /* repeat until fields exhausted? */
                    *t = '\0';
-                   SvCUR_set(PL_formtarget, t - SvPVX(PL_formtarget));
+                   SvCUR_set(PL_formtarget, t - SvPVX_const(PL_formtarget));
                    lines += FmLINES(PL_formtarget);
                    if (lines == 200) {
                        arg = t - linemark;
                        if (strnEQ(linemark, linemark - arg, arg))
                            DIE(aTHX_ "Runaway format");
                    }
+                   if (targ_is_utf8)
+                       SvUTF8_on(PL_formtarget);
                    FmLINES(PL_formtarget) = lines;
                    SP = ORIGMARK;
                    RETURNOP(cLISTOP->op_first);
@@ -715,33 +865,37 @@ PP(pp_formline)
            break;
 
        case FF_MORE:
-           s = chophere;
-           send = item + len;
-           if (chopspace) {
-               while (*s && isSPACE(*s) && s < send)
-                   s++;
-           }
-           if (s < send) {
-               arg = fieldsize - itemsize;
-               if (arg) {
-                   fieldsize -= arg;
-                   while (arg-- > 0)
-                       *t++ = ' ';
+           {
+               const char *s = chophere;
+               const char *send = item + len;
+               if (chopspace) {
+                   while (*s && isSPACE(*s) && s < send)
+                       s++;
                }
-               s = t - 3;
-               if (strnEQ(s,"   ",3)) {
-                   while (s > SvPVX(PL_formtarget) && isSPACE(s[-1]))
-                       s--;
+               if (s < send) {
+                   char *s1;
+                   arg = fieldsize - itemsize;
+                   if (arg) {
+                       fieldsize -= arg;
+                       while (arg-- > 0)
+                           *t++ = ' ';
+                   }
+                   s1 = t - 3;
+                   if (strnEQ(s1,"   ",3)) {
+                       while (s1 > SvPVX_const(PL_formtarget) && isSPACE(s1[-1]))
+                           s1--;
+                   }
+                   *s1++ = '.';
+                   *s1++ = '.';
+                   *s1++ = '.';
                }
-               *s++ = '.';
-               *s++ = '.';
-               *s++ = '.';
+               break;
            }
-           break;
-
        case FF_END:
            *t = '\0';
-           SvCUR_set(PL_formtarget, t - SvPVX(PL_formtarget));
+           SvCUR_set(PL_formtarget, t - SvPVX_const(PL_formtarget));
+           if (targ_is_utf8)
+               SvUTF8_on(PL_formtarget);
            FmLINES(PL_formtarget) += lines;
            SP = ORIGMARK;
            RETPUSHYES;
@@ -751,7 +905,7 @@ PP(pp_formline)
 
 PP(pp_grepstart)
 {
-    dSP;
+    dVAR; dSP;
     SV *src;
 
     if (PL_stack_base + *PL_markstack_ptr == SP) {
@@ -766,14 +920,19 @@ PP(pp_grepstart)
     ENTER;                                     /* enter outer scope */
 
     SAVETMPS;
-    /* SAVE_DEFSV does *not* suffice here for USE_5005THREADS */
-    SAVESPTR(DEFSV);
+    if (PL_op->op_private & OPpGREP_LEX)
+       SAVESPTR(PAD_SVl(PL_op->op_targ));
+    else
+       SAVE_DEFSV;
     ENTER;                                     /* enter inner scope */
     SAVEVPTR(PL_curpm);
 
     src = PL_stack_base[*PL_markstack_ptr];
     SvTEMP_off(src);
-    DEFSV = src;
+    if (PL_op->op_private & OPpGREP_LEX)
+       PAD_SVl(PL_op->op_targ) = src;
+    else
+       DEFSV = src;
 
     PUTBACK;
     if (PL_op->op_type == OP_MAPSTART)
@@ -788,7 +947,8 @@ PP(pp_mapstart)
 
 PP(pp_mapwhile)
 {
-    dSP;
+    dVAR; dSP;
+    const I32 gimme = GIMME_V;
     I32 items = (SP - PL_stack_base) - *PL_markstack_ptr; /* how many new items */
     I32 count;
     I32 shift;
@@ -799,7 +959,7 @@ PP(pp_mapwhile)
     ++PL_markstack_ptr[-1];
 
     /* if there are new items, push them into the destination list */
-    if (items) {
+    if (items && gimme != G_VOID) {
        /* might need to make room back there first */
        if (items > PL_markstack_ptr[-1] - PL_markstack_ptr[-2]) {
            /* XXX this implementation is very pessimal because the stack
@@ -825,7 +985,7 @@ PP(pp_mapwhile)
             * irrelevant.  --jhi */
             if (shift < count)
                 shift = count; /* Avoid shifting too often --Ben Tilly */
-       
+
            EXTEND(SP,shift);
            src = SP;
            dst = (SP += shift);
@@ -836,14 +996,24 @@ PP(pp_mapwhile)
        }
        /* copy the new items down to the destination list */
        dst = PL_stack_base + (PL_markstack_ptr[-2] += items) - 1;
-       while (items--)
-           *dst-- = SvTEMP(TOPs) ? POPs : sv_mortalcopy(POPs);
+       if (gimme == G_ARRAY) {
+           while (items-- > 0)
+               *dst-- = SvTEMP(TOPs) ? POPs : sv_mortalcopy(POPs);
+       }
+       else {
+           /* scalar context: we don't care about which values map returns
+            * (we use undef here). And so we certainly don't want to do mortal
+            * copies of meaningless values. */
+           while (items-- > 0) {
+               (void)POPs;
+               *dst-- = &PL_sv_undef;
+           }
+       }
     }
     LEAVE;                                     /* exit inner scope */
 
     /* All done yet? */
     if (PL_markstack_ptr[-1] > *PL_markstack_ptr) {
-       I32 gimme = GIMME_V;
 
        (void)POPMARK;                          /* pop top */
        LEAVE;                                  /* exit outer scope */
@@ -852,8 +1022,15 @@ PP(pp_mapwhile)
        (void)POPMARK;                          /* pop dst */
        SP = PL_stack_base + POPMARK;           /* pop original mark */
        if (gimme == G_SCALAR) {
-           dTARGET;
-           XPUSHi(items);
+           if (PL_op->op_private & OPpGREP_LEX) {
+               SV* sv = sv_newmortal();
+               sv_setiv(sv, items);
+               PUSHs(sv);
+           }
+           else {
+               dTARGET;
+               XPUSHi(items);
+           }
        }
        else if (gimme == G_ARRAY)
            SP += items;
@@ -868,7 +1045,10 @@ PP(pp_mapwhile)
        /* set $_ to the new source item */
        src = PL_stack_base[PL_markstack_ptr[-1]];
        SvTEMP_off(src);
-       DEFSV = src;
+       if (PL_op->op_private & OPpGREP_LEX)
+           PAD_SVl(PL_op->op_targ) = src;
+       else
+           DEFSV = src;
 
        RETURNOP(cLOGOP->op_other);
     }
@@ -895,21 +1075,22 @@ PP(pp_flip)
     }
     else {
        dTOPss;
-       SV *targ = PAD_SV(PL_op->op_targ);
-       int flip = 0;
+       SV * const targ = PAD_SV(PL_op->op_targ);
+       int flip = 0;
 
-       if (PL_op->op_private & OPpFLIP_LINENUM) {
+       if (PL_op->op_private & OPpFLIP_LINENUM) {
            if (GvIO(PL_last_in_gv)) {
                flip = SvIV(sv) == (IV)IoLINES(GvIOp(PL_last_in_gv));
            }
            else {
-               GV *gv = gv_fetchpv(".", TRUE, SVt_PV);
-               if (gv && GvSV(gv)) flip = SvIV(sv) == SvIV(GvSV(gv));
+               GV * const gv = gv_fetchpv(".", TRUE, SVt_PV);
+               if (gv && GvSV(gv))
+                   flip = SvIV(sv) == SvIV(GvSV(gv));
            }
-       } else {
-           flip = SvTRUE(sv);
-       }
-       if (flip) {
+       } else {
+           flip = SvTRUE(sv);
+       }
+       if (flip) {
            sv_setiv(PAD_SV(cUNOP->op_first->op_targ), 1);
            if (PL_op->op_flags & OPf_SPECIAL) {
                sv_setiv(targ, 1);
@@ -922,33 +1103,38 @@ PP(pp_flip)
                RETURNOP(((LOGOP*)cUNOP->op_first)->op_other);
            }
        }
-       sv_setpv(TARG, "");
+       sv_setpvn(TARG, "", 0);
        SETs(targ);
        RETURN;
     }
 }
 
+/* This code tries to decide if "$left .. $right" should use the
+   magical string increment, or if the range is numeric (we make
+   an exception for .."0" [#18165]). AMS 20021031. */
+
+#define RANGE_IS_NUMERIC(left,right) ( \
+       SvNIOKp(left)  || (SvOK(left)  && !SvPOKp(left))  || \
+       SvNIOKp(right) || (SvOK(right) && !SvPOKp(right)) || \
+       (((!SvOK(left) && SvOK(right)) || ((!SvOK(left) || \
+          looks_like_number(left)) && SvPOKp(left) && *SvPVX_const(left) != '0')) \
+         && (!SvOK(right) || looks_like_number(right))))
+
 PP(pp_flop)
 {
     dSP;
 
     if (GIMME == G_ARRAY) {
        dPOPPOPssrl;
-       register I32 i, j;
-       register SV *sv;
-       I32 max;
-
-       if (SvGMAGICAL(left))
-           mg_get(left);
-       if (SvGMAGICAL(right))
-           mg_get(right);
-
-       if (SvNIOKp(left) || !SvPOKp(left) ||
-           SvNIOKp(right) || !SvPOKp(right) ||
-           (looks_like_number(left) && *SvPVX(left) != '0' &&
-            looks_like_number(right) && *SvPVX(right) != '0'))
-       {
-           if (SvNV(left) < IV_MIN || SvNV(right) > IV_MAX)
+
+       SvGETMAGIC(left);
+       SvGETMAGIC(right);
+
+       if (RANGE_IS_NUMERIC(left,right)) {
+           register IV i, j;
+           IV max;
+           if ((SvOK(left) && SvNV(left) < IV_MIN) ||
+               (SvOK(right) && SvNV(right) > IV_MAX))
                DIE(aTHX_ "Range iterator outside integer range");
            i = SvIV(left);
            max = SvIV(right);
@@ -960,20 +1146,20 @@ PP(pp_flop)
            else
                j = 0;
            while (j--) {
-               sv = sv_2mortal(newSViv(i++));
+               SV * const sv = sv_2mortal(newSViv(i++));
                PUSHs(sv);
            }
        }
        else {
-           SV *final = sv_mortalcopy(right);
-           STRLEN len, n_a;
-           char *tmps = SvPV(final, len);
+           SV * const final = sv_mortalcopy(right);
+           STRLEN len;
+           const char * const tmps = SvPV_const(final, len);
 
-           sv = sv_mortalcopy(left);
-           SvPV_force(sv,n_a);
+           SV *sv = sv_mortalcopy(left);
+           SvPV_force_nolen(sv);
            while (!SvNIOKp(sv) && SvCUR(sv) <= len) {
                XPUSHs(sv);
-               if (strEQ(SvPVX(sv),tmps))
+               if (strEQ(SvPVX_const(sv),tmps))
                    break;
                sv = sv_2mortal(newSVsv(sv));
                sv_inc(sv);
@@ -982,7 +1168,7 @@ PP(pp_flop)
     }
     else {
        dTOPss;
-       SV *targ = PAD_SV(cUNOP->op_first->op_targ);
+       SV * const targ = PAD_SV(cUNOP->op_first->op_targ);
        int flop = 0;
        sv_inc(targ);
 
@@ -991,7 +1177,7 @@ PP(pp_flop)
                flop = SvIV(sv) == (IV)IoLINES(GvIOp(PL_last_in_gv));
            }
            else {
-               GV *gv = gv_fetchpv(".", TRUE, SVt_PV);
+               GV * const gv = gv_fetchpv(".", TRUE, SVt_PV);
                if (gv && GvSV(gv)) flop = SvIV(sv) == SvIV(GvSV(gv));
            }
        }
@@ -1001,7 +1187,7 @@ PP(pp_flop)
 
        if (flop) {
            sv_setiv(PAD_SV(((UNOP*)cUNOP->op_first)->op_first->op_targ), 0);
-           sv_catpv(targ, "E0");
+           sv_catpvn(targ, "E0", 2);
        }
        SETs(targ);
     }
@@ -1011,43 +1197,37 @@ PP(pp_flop)
 
 /* Control. */
 
+static const char * const context_name[] = {
+    "pseudo-block",
+    "subroutine",
+    "eval",
+    "loop",
+    "substitution",
+    "block",
+    "format"
+};
+
 STATIC I32
-S_dopoptolabel(pTHX_ char *label)
+S_dopoptolabel(pTHX_ const char *label)
 {
     register I32 i;
-    register PERL_CONTEXT *cx;
 
     for (i = cxstack_ix; i >= 0; i--) {
-       cx = &cxstack[i];
+       register const PERL_CONTEXT * const cx = &cxstack[i];
        switch (CxTYPE(cx)) {
        case CXt_SUBST:
-           if (ckWARN(WARN_EXITING))
-               Perl_warner(aTHX_ packWARN(WARN_EXITING), "Exiting substitution via %s",
-                       OP_NAME(PL_op));
-           break;
        case CXt_SUB:
-           if (ckWARN(WARN_EXITING))
-               Perl_warner(aTHX_ packWARN(WARN_EXITING), "Exiting subroutine via %s",
-                       OP_NAME(PL_op));
-           break;
        case CXt_FORMAT:
-           if (ckWARN(WARN_EXITING))
-               Perl_warner(aTHX_ packWARN(WARN_EXITING), "Exiting format via %s",
-                       OP_NAME(PL_op));
-           break;
        case CXt_EVAL:
-           if (ckWARN(WARN_EXITING))
-               Perl_warner(aTHX_ packWARN(WARN_EXITING), "Exiting eval via %s",
-                       OP_NAME(PL_op));
-           break;
        case CXt_NULL:
            if (ckWARN(WARN_EXITING))
-               Perl_warner(aTHX_ packWARN(WARN_EXITING), "Exiting pseudo-block via %s",
-                       OP_NAME(PL_op));
-           return -1;
+               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:
-           if (!cx->blk_loop.label ||
-             strNE(label, cx->blk_loop.label) ) {
+           if ( !cx->blk_loop.label || strNE(label, cx->blk_loop.label) ) {
                DEBUG_l(Perl_deb(aTHX_ "(Skipping label #%ld %s)\n",
                        (long)i, cx->blk_loop.label));
                continue;
@@ -1062,16 +1242,14 @@ S_dopoptolabel(pTHX_ char *label)
 I32
 Perl_dowantarray(pTHX)
 {
-    I32 gimme = block_gimme();
+    const I32 gimme = block_gimme();
     return (gimme == G_VOID) ? G_SCALAR : gimme;
 }
 
 I32
 Perl_block_gimme(pTHX)
 {
-    I32 cxix;
-
-    cxix = dopoptosub(cxstack_ix);
+    const I32 cxix = dopoptosub(cxstack_ix);
     if (cxix < 0)
        return G_VOID;
 
@@ -1092,9 +1270,7 @@ Perl_block_gimme(pTHX)
 I32
 Perl_is_lvalue_sub(pTHX)
 {
-    I32 cxix;
-
-    cxix = dopoptosub(cxstack_ix);
+    const I32 cxix = dopoptosub(cxstack_ix);
     assert(cxix >= 0);  /* We should only be called from inside subs */
 
     if (cxstack[cxix].blk_sub.lval && CvLVALUE(cxstack[cxix].blk_sub.cv))
@@ -1110,12 +1286,11 @@ S_dopoptosub(pTHX_ I32 startingblock)
 }
 
 STATIC I32
-S_dopoptosub_at(pTHX_ PERL_CONTEXT *cxstk, I32 startingblock)
+S_dopoptosub_at(pTHX_ const PERL_CONTEXT *cxstk, I32 startingblock)
 {
     I32 i;
-    register PERL_CONTEXT *cx;
     for (i = startingblock; i >= 0; i--) {
-       cx = &cxstk[i];
+       register const PERL_CONTEXT * const cx = &cxstk[i];
        switch (CxTYPE(cx)) {
        default:
            continue;
@@ -1133,9 +1308,8 @@ STATIC I32
 S_dopoptoeval(pTHX_ I32 startingblock)
 {
     I32 i;
-    register PERL_CONTEXT *cx;
     for (i = startingblock; i >= 0; i--) {
-       cx = &cxstack[i];
+       register const PERL_CONTEXT *cx = &cxstack[i];
        switch (CxTYPE(cx)) {
        default:
            continue;
@@ -1151,35 +1325,20 @@ STATIC I32
 S_dopoptoloop(pTHX_ I32 startingblock)
 {
     I32 i;
-    register PERL_CONTEXT *cx;
     for (i = startingblock; i >= 0; i--) {
-       cx = &cxstack[i];
+       register const PERL_CONTEXT * const cx = &cxstack[i];
        switch (CxTYPE(cx)) {
        case CXt_SUBST:
-           if (ckWARN(WARN_EXITING))
-               Perl_warner(aTHX_ packWARN(WARN_EXITING), "Exiting substitution via %s",
-                       OP_NAME(PL_op));
-           break;
        case CXt_SUB:
-           if (ckWARN(WARN_EXITING))
-               Perl_warner(aTHX_ packWARN(WARN_EXITING), "Exiting subroutine via %s",
-                       OP_NAME(PL_op));
-           break;
        case CXt_FORMAT:
-           if (ckWARN(WARN_EXITING))
-               Perl_warner(aTHX_ packWARN(WARN_EXITING), "Exiting format via %s",
-                       OP_NAME(PL_op));
-           break;
        case CXt_EVAL:
-           if (ckWARN(WARN_EXITING))
-               Perl_warner(aTHX_ packWARN(WARN_EXITING), "Exiting eval via %s",
-                       OP_NAME(PL_op));
-           break;
        case CXt_NULL:
            if (ckWARN(WARN_EXITING))
-               Perl_warner(aTHX_ packWARN(WARN_EXITING), "Exiting pseudo-block via %s",
-                       OP_NAME(PL_op));
-           return -1;
+               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:
            DEBUG_l( Perl_deb(aTHX_ "(Found loop #%ld)\n", (long)i));
            return i;
@@ -1191,12 +1350,11 @@ S_dopoptoloop(pTHX_ I32 startingblock)
 void
 Perl_dounwind(pTHX_ I32 cxix)
 {
-    register PERL_CONTEXT *cx;
     I32 optype;
 
     while (cxstack_ix > cxix) {
        SV *sv;
-       cx = &cxstack[cxstack_ix];
+        register PERL_CONTEXT *cx = &cxstack[cxstack_ix];
        DEBUG_l(PerlIO_printf(Perl_debug_log, "Unwinding block %ld, type %s\n",
                              (long) cxstack_ix, PL_block_type[CxTYPE(cx)]));
        /* Note: we don't need to restore the base context info till the end. */
@@ -1222,6 +1380,7 @@ Perl_dounwind(pTHX_ I32 cxix)
        }
        cxstack_ix--;
     }
+    PERL_UNUSED_VAR(optype);
 }
 
 void
@@ -1237,28 +1396,25 @@ Perl_qerror(pTHX_ SV *err)
 }
 
 OP *
-Perl_die_where(pTHX_ char *message, STRLEN msglen)
+Perl_die_where(pTHX_ const char *message, STRLEN msglen)
 {
-    STRLEN n_a;
-    IO *io;
-    MAGIC *mg;
+    dVAR;
 
     if (PL_in_eval) {
        I32 cxix;
-       register PERL_CONTEXT *cx;
        I32 gimme;
-       SV **newsp;
 
        if (message) {
            if (PL_in_eval & EVAL_KEEPERR) {
-               static char prefix[] = "\t(in cleanup) ";
-               SV *err = ERRSV;
-               char *e = Nullch;
+                static const char prefix[] = "\t(in cleanup) ";
+               SV * const err = ERRSV;
+                const char *e = Nullch;
                if (!SvPOK(err))
-                   sv_setpv(err,"");
+                   sv_setpvn(err,"",0);
                else if (SvCUR(err) >= sizeof(prefix)+msglen-1) {
-                   e = SvPV(err, n_a);
-                   e += n_a - msglen;
+                   STRLEN len;
+                   e = SvPV_const(err, len);
+                   e += len - msglen;
                    if (*e != *message || strNE(e,message))
                        e = Nullch;
                }
@@ -1267,8 +1423,8 @@ Perl_die_where(pTHX_ char *message, STRLEN msglen)
                    sv_catpvn(err, prefix, sizeof(prefix)-1);
                    sv_catpvn(err, message, msglen);
                    if (ckWARN(WARN_MISC)) {
-                       STRLEN start = SvCUR(err)-msglen-sizeof(prefix)+1;
-                       Perl_warner(aTHX_ packWARN(WARN_MISC), SvPVX(err)+start);
+                       const STRLEN start = SvCUR(err)-msglen-sizeof(prefix)+1;
+                       Perl_warner(aTHX_ packWARN(WARN_MISC), SvPVX_const(err)+start);
                    }
                }
            }
@@ -1276,8 +1432,6 @@ Perl_die_where(pTHX_ char *message, STRLEN msglen)
                sv_setpvn(ERRSV, message, msglen);
            }
        }
-       else
-           message = SvPVx(ERRSV, msglen);
 
        while ((cxix = dopoptoeval(cxstack_ix)) < 0
               && PL_curstackinfo->si_prev)
@@ -1288,12 +1442,16 @@ Perl_die_where(pTHX_ char *message, STRLEN msglen)
 
        if (cxix >= 0) {
            I32 optype;
+           register PERL_CONTEXT *cx;
+           SV **newsp;
 
            if (cxix < cxstack_ix)
                dounwind(cxix);
 
            POPBLOCK(cx,PL_curpm);
            if (CxTYPE(cx) != CXt_EVAL) {
+               if (!message)
+                   message = SvPVx_const(ERRSV, msglen);
                PerlIO_write(Perl_error_log, "panic: die ", 11);
                PerlIO_write(Perl_error_log, message, msglen);
                my_exit(1);
@@ -1313,40 +1471,21 @@ Perl_die_where(pTHX_ char *message, STRLEN msglen)
            PL_curcop = cx->blk_oldcop;
 
            if (optype == OP_REQUIRE) {
-               char* msg = SvPVx(ERRSV, n_a);
+                const char* const msg = SvPVx_nolen_const(ERRSV);
+               SV * const nsv = cx->blk_eval.old_namesv;
+                (void)hv_store(GvHVn(PL_incgv), SvPVX_const(nsv), SvCUR(nsv),
+                               &PL_sv_undef, 0);
                DIE(aTHX_ "%sCompilation failed in require",
                    *msg ? msg : "Unknown error\n");
            }
-           return pop_return();
+           assert(CxTYPE(cx) == CXt_EVAL);
+           return cx->blk_eval.retop;
        }
     }
     if (!message)
-       message = SvPVx(ERRSV, msglen);
+       message = SvPVx_const(ERRSV, msglen);
 
-    /* if STDERR is tied, print to it instead */
-    if (PL_stderrgv && (io = GvIOp(PL_stderrgv))
-       && (mg = SvTIED_mg((SV*)io, PERL_MAGIC_tiedscalar))) {
-       dSP; ENTER;
-       PUSHMARK(SP);
-       XPUSHs(SvTIED_obj((SV*)io, mg));
-       XPUSHs(sv_2mortal(newSVpvn(message, msglen)));
-       PUTBACK;
-       call_method("PRINT", G_SCALAR);
-       LEAVE;
-    }
-    else {
-#ifdef USE_SFIO
-       /* SFIO can really mess with your errno */
-       int e = errno;
-#endif
-       PerlIO *serr = Perl_error_log;
-
-       PERL_WRITE_MSG_TO_CONSOLE(serr, message, msglen);
-       (void)PerlIO_flush(serr);
-#ifdef USE_SFIO
-       errno = e;
-#endif
-    }
+    write_to_stderr(message, msglen);
     my_failure_exit();
     /* NOTREACHED */
     return 0;
@@ -1378,18 +1517,48 @@ PP(pp_orassign)
     else
        RETURNOP(cLOGOP->op_other);
 }
-       
+
+PP(pp_dorassign)
+{
+    dSP;
+    register SV* sv;
+
+    sv = TOPs;
+    if (!sv || !SvANY(sv)) {
+       RETURNOP(cLOGOP->op_other);
+    }
+
+    switch (SvTYPE(sv)) {
+    case SVt_PVAV:
+       if (AvMAX(sv) >= 0 || SvGMAGICAL(sv) || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
+           RETURN;
+       break;
+    case SVt_PVHV:
+       if (HvARRAY(sv) || SvGMAGICAL(sv) || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
+           RETURN;
+       break;
+    case SVt_PVCV:
+       if (CvROOT(sv) || CvXSUB(sv))
+           RETURN;
+       break;
+    default:
+       SvGETMAGIC(sv);
+       if (SvOK(sv))
+           RETURN;
+    }
+
+    RETURNOP(cLOGOP->op_other);
+}
+
 PP(pp_caller)
 {
     dSP;
     register I32 cxix = dopoptosub(cxstack_ix);
-    register PERL_CONTEXT *cx;
-    register PERL_CONTEXT *ccstack = cxstack;
-    PERL_SI *top_si = PL_curstackinfo;
-    I32 dbcxix;
+    register const PERL_CONTEXT *cx;
+    register const PERL_CONTEXT *ccstack = cxstack;
+    const PERL_SI *top_si = PL_curstackinfo;
     I32 gimme;
-    char *stashname;
-    SV *sv;
+    const char *stashname;
     I32 count = 0;
 
     if (MAXARG)
@@ -1409,7 +1578,8 @@ PP(pp_caller)
             }
            RETURN;
        }
-       if (PL_DBsub && cxix >= 0 &&
+       /* caller() should not report the automatic calls to &DB::sub */
+       if (PL_DBsub && GvCV(PL_DBsub) && cxix >= 0 &&
                ccstack[cxix].blk_sub.cv == GvCV(PL_DBsub))
            count++;
        if (!count--)
@@ -1419,10 +1589,11 @@ PP(pp_caller)
 
     cx = &ccstack[cxix];
     if (CxTYPE(cx) == CXt_SUB || CxTYPE(cx) == CXt_FORMAT) {
-        dbcxix = dopoptosub_at(ccstack, cxix - 1);
+        const I32 dbcxix = dopoptosub_at(ccstack, cxix - 1);
        /* We expect that ccstack[dbcxix] is CXt_SUB, anyway, the
           field below is defined for any cx. */
-       if (PL_DBsub && dbcxix >= 0 && ccstack[dbcxix].blk_sub.cv == GvCV(PL_DBsub))
+       /* caller() should not report the automatic calls to &DB::sub */
+       if (PL_DBsub && GvCV(PL_DBsub) && dbcxix >= 0 && ccstack[dbcxix].blk_sub.cv == GvCV(PL_DBsub))
            cx = &ccstack[dbcxix];
     }
 
@@ -1450,11 +1621,18 @@ PP(pp_caller)
     if (!MAXARG)
        RETURN;
     if (CxTYPE(cx) == CXt_SUB || CxTYPE(cx) == CXt_FORMAT) {
+       GV *cvgv = CvGV(ccstack[cxix].blk_sub.cv);
        /* So is ccstack[dbcxix]. */
-       sv = NEWSV(49, 0);
-       gv_efullname3(sv, CvGV(ccstack[cxix].blk_sub.cv), Nullch);
-       PUSHs(sv_2mortal(sv));
-       PUSHs(sv_2mortal(newSViv((I32)cx->blk_sub.hasargs)));
+       if (isGV(cvgv)) {
+           SV * const sv = NEWSV(49, 0);
+           gv_efullname3(sv, cvgv, Nullch);
+           PUSHs(sv_2mortal(sv));
+           PUSHs(sv_2mortal(newSViv((I32)cx->blk_sub.hasargs)));
+       }
+       else {
+           PUSHs(sv_2mortal(newSVpvn("(unknown)",9)));
+           PUSHs(sv_2mortal(newSViv((I32)cx->blk_sub.hasargs)));
+       }
     }
     else {
        PUSHs(sv_2mortal(newSVpvn("(eval)",6)));
@@ -1489,8 +1667,8 @@ PP(pp_caller)
     if (CxTYPE(cx) == CXt_SUB && cx->blk_sub.hasargs
        && CopSTASH_eq(PL_curcop, PL_debstash))
     {
-       AV *ary = cx->blk_sub.argarray;
-       int off = AvARRAY(ary) - AvALLOC(ary);
+       AV * const ary = cx->blk_sub.argarray;
+       const int off = AvARRAY(ary) - AvALLOC(ary);
 
        if (!PL_dbargs) {
            GV* tmpgv;
@@ -1518,8 +1696,18 @@ PP(pp_caller)
                (old_warnings == pWARN_STD && (PL_dowarn & G_WARN_ON) == 0))
             mask = newSVpvn(WARN_NONEstring, WARNsize) ;
         else if (old_warnings == pWARN_ALL ||
-                 (old_warnings == pWARN_STD && PL_dowarn & G_WARN_ON))
-            mask = newSVpvn(WARN_ALLstring, WARNsize) ;
+                 (old_warnings == pWARN_STD && PL_dowarn & G_WARN_ON)) {
+           /* Get the bit mask for $warnings::Bits{all}, because
+            * it could have been extended by warnings::register */
+           SV **bits_all;
+           HV *bits = get_hv("warnings::Bits", FALSE);
+           if (bits && (bits_all=hv_fetch(bits, "all", 3, FALSE))) {
+               mask = newSVsv(*bits_all);
+           }
+           else {
+               mask = newSVpvn(WARN_ALLstring, WARNsize) ;
+           }
+       }
         else
             mask = newSVsv(old_warnings);
         PUSHs(sv_2mortal(mask));
@@ -1530,13 +1718,12 @@ PP(pp_caller)
 PP(pp_reset)
 {
     dSP;
-    char *tmps;
-    STRLEN n_a;
+    const char *tmps;
 
     if (MAXARG < 1)
        tmps = "";
     else
-       tmps = POPpx;
+       tmps = POPpconstx;
     sv_reset(tmps, CopSTASH(PL_curcop));
     PUSHs(&PL_sv_yes);
     RETURN;
@@ -1547,19 +1734,23 @@ PP(pp_lineseq)
     return NORMAL;
 }
 
+/* like pp_nextstate, but used instead when the debugger is active */
+
 PP(pp_dbstate)
 {
+    dVAR;
     PL_curcop = (COP*)PL_op;
     TAINT_NOT;         /* Each statement is presumed innocent */
     PL_stack_sp = PL_stack_base + cxstack[cxstack_ix].blk_oldsp;
     FREETMPS;
 
-    if (PL_op->op_private || SvIV(PL_DBsingle) || SvIV(PL_DBsignal) || SvIV(PL_DBtrace))
+    if (PL_op->op_flags & OPf_SPECIAL /* breakpoint */
+           || SvIV(PL_DBsingle) || SvIV(PL_DBsignal) || SvIV(PL_DBtrace))
     {
        dSP;
        register CV *cv;
        register PERL_CONTEXT *cx;
-       I32 gimme = G_ARRAY;
+       const I32 gimme = G_ARRAY;
        U8 hasargs;
        GV *gv;
 
@@ -1581,14 +1772,24 @@ PP(pp_dbstate)
        hasargs = 0;
        SPAGAIN;
 
-       push_return(PL_op->op_next);
-       PUSHBLOCK(cx, CXt_SUB, SP);
-       PUSHSUB(cx);
-       CvDEPTH(cv)++;
-       (void)SvREFCNT_inc(cv);
-       SAVEVPTR(PL_curpad);
-       PL_curpad = AvARRAY((AV*)*av_fetch(CvPADLIST(cv),1,FALSE));
-       RETURNOP(CvSTART(cv));
+       if (CvXSUB(cv)) {
+           CvDEPTH(cv)++;
+           PUSHMARK(SP);
+           (void)(*CvXSUB(cv))(aTHX_ cv);
+           CvDEPTH(cv)--;
+           FREETMPS;
+           LEAVE;
+           return NORMAL;
+       }
+       else {
+           PUSHBLOCK(cx, CXt_SUB, SP);
+           PUSHSUB_DB(cx);
+           cx->blk_sub.retop = PL_op->op_next;
+           CvDEPTH(cv)++;
+           SAVECOMPPAD();
+           PAD_SET_CUR_NOSAVE(CvPADLIST(cv), 1);
+           RETURNOP(CvSTART(cv));
+       }
     }
     else
        return NORMAL;
@@ -1601,9 +1802,9 @@ PP(pp_scope)
 
 PP(pp_enteriter)
 {
-    dSP; dMARK;
+    dVAR; dSP; dMARK;
     register PERL_CONTEXT *cx;
-    I32 gimme = GIMME_V;
+    const I32 gimme = GIMME_V;
     SV **svp;
     U32 cxtype = CXt_LOOP;
 #ifdef USE_ITHREADS
@@ -1613,17 +1814,14 @@ PP(pp_enteriter)
     ENTER;
     SAVETMPS;
 
-#ifdef USE_5005THREADS
-    if (PL_op->op_flags & OPf_SPECIAL) {
-       svp = &THREADSV(PL_op->op_targ);        /* per-thread variable */
-       SAVEGENERICSV(*svp);
-       *svp = NEWSV(0,0);
-    }
-    else
-#endif /* USE_5005THREADS */
     if (PL_op->op_targ) {
+       if (PL_op->op_private & OPpLVAL_INTRO) { /* for my $x (...) */
+           SvPADSTALE_off(PAD_SVl(PL_op->op_targ));
+           SAVESETSVFLAGS(PAD_SVl(PL_op->op_targ),
+                   SVs_PADSTALE, SVs_PADSTALE);
+       }
 #ifndef USE_ITHREADS
-       svp = &PL_curpad[PL_op->op_targ];               /* "my" variable */
+       svp = &PAD_SVl(PL_op->op_targ);         /* "my" variable */
        SAVESPTR(*svp);
 #else
        SAVEPADSV(PL_op->op_targ);
@@ -1653,26 +1851,42 @@ PP(pp_enteriter)
        cx->blk_loop.iterary = (AV*)SvREFCNT_inc(POPs);
        if (SvTYPE(cx->blk_loop.iterary) != SVt_PVAV) {
            dPOPss;
-           if (SvNIOKp(sv) || !SvPOKp(sv) ||
-               SvNIOKp(cx->blk_loop.iterary) || !SvPOKp(cx->blk_loop.iterary) ||
-               (looks_like_number(sv) && *SvPVX(sv) != '0' &&
-                looks_like_number((SV*)cx->blk_loop.iterary) &&
-                *SvPVX(cx->blk_loop.iterary) != '0'))
-           {
-                if (SvNV(sv) < IV_MIN ||
-                    SvNV((SV*)cx->blk_loop.iterary) >= IV_MAX)
-                    DIE(aTHX_ "Range iterator outside integer range");
-                cx->blk_loop.iterix = SvIV(sv);
-                cx->blk_loop.itermax = SvIV((SV*)cx->blk_loop.iterary);
+           SV *right = (SV*)cx->blk_loop.iterary;
+           SvGETMAGIC(sv);
+           SvGETMAGIC(right);
+           if (RANGE_IS_NUMERIC(sv,right)) {
+               if ((SvOK(sv) && SvNV(sv) < IV_MIN) ||
+                   (SvOK(right) && SvNV(right) >= IV_MAX))
+                   DIE(aTHX_ "Range iterator outside integer range");
+               cx->blk_loop.iterix = SvIV(sv);
+               cx->blk_loop.itermax = SvIV(right);
+#ifdef DEBUGGING
+               /* for correct -Dstv display */
+               cx->blk_oldsp = sp - PL_stack_base;
+#endif
            }
-           else
+           else {
                cx->blk_loop.iterlval = newSVsv(sv);
+               (void) SvPV_force_nolen(cx->blk_loop.iterlval);
+               (void) SvPV_nolen_const(right);
+           }
+       }
+       else if (PL_op->op_private & OPpITER_REVERSED) {
+           cx->blk_loop.itermax = -1;
+           cx->blk_loop.iterix = AvFILL(cx->blk_loop.iterary);
+
        }
     }
     else {
        cx->blk_loop.iterary = PL_curstack;
        AvFILLp(PL_curstack) = SP - PL_stack_base;
-       cx->blk_loop.iterix = MARK - PL_stack_base;
+       if (PL_op->op_private & OPpITER_REVERSED) {
+           cx->blk_loop.itermax = MARK - PL_stack_base;
+           cx->blk_loop.iterix = cx->blk_oldsp;
+       }
+       else {
+           cx->blk_loop.iterix = MARK - PL_stack_base;
+       }
     }
 
     RETURN;
@@ -1680,9 +1894,9 @@ PP(pp_enteriter)
 
 PP(pp_enterloop)
 {
-    dSP;
+    dVAR; dSP;
     register PERL_CONTEXT *cx;
-    I32 gimme = GIMME_V;
+    const I32 gimme = GIMME_V;
 
     ENTER;
     SAVETMPS;
@@ -1696,7 +1910,7 @@ PP(pp_enterloop)
 
 PP(pp_leaveloop)
 {
-    dSP;
+    dVAR; dSP;
     register PERL_CONTEXT *cx;
     I32 gimme;
     SV **newsp;
@@ -1704,6 +1918,7 @@ PP(pp_leaveloop)
     SV **mark;
 
     POPBLOCK(cx,newpm);
+    assert(CxTYPE(cx) == CXt_LOOP);
     mark = newsp;
     newsp = PL_stack_base + cx->blk_loop.resetsp;
 
@@ -1736,7 +1951,7 @@ PP(pp_leaveloop)
 
 PP(pp_return)
 {
-    dSP; dMARK;
+    dVAR; dSP; dMARK;
     I32 cxix;
     register PERL_CONTEXT *cx;
     bool popsub2 = FALSE;
@@ -1746,6 +1961,7 @@ PP(pp_return)
     PMOP *newpm;
     I32 optype = 0;
     SV *sv;
+    OP *retop;
 
     if (PL_curstackinfo->si_type == PERLSI_SORT) {
        if (cxstack_ix == PL_sortcxix
@@ -1769,11 +1985,14 @@ PP(pp_return)
     switch (CxTYPE(cx)) {
     case CXt_SUB:
        popsub2 = TRUE;
+       retop = cx->blk_sub.retop;
+       cxstack_ix++; /* preserve cx entry on stack for use by POPSUB */
        break;
     case CXt_EVAL:
        if (!(PL_in_eval & EVAL_KEEPERR))
            clear_errsv = TRUE;
        POPEVAL(cx);
+       retop = cx->blk_eval.retop;
        if (CxTRYBLOCK(cx))
            break;
        lex_end();
@@ -1781,13 +2000,14 @@ PP(pp_return)
            (MARK == SP || (gimme == G_SCALAR && !SvTRUE(*SP))) )
        {
            /* Unassume the success we assumed earlier. */
-           SV *nsv = cx->blk_eval.old_namesv;
-           (void)hv_delete(GvHVn(PL_incgv), SvPVX(nsv), SvCUR(nsv), G_DISCARD);
-           DIE(aTHX_ "%s did not return a true value", SvPVX(nsv));
+           SV * const nsv = cx->blk_eval.old_namesv;
+           (void)hv_delete(GvHVn(PL_incgv), SvPVX_const(nsv), SvCUR(nsv), G_DISCARD);
+           DIE(aTHX_ "%"SVf" did not return a true value", nsv);
        }
        break;
     case CXt_FORMAT:
        POPFORMAT(cx);
+       retop = cx->blk_sub.retop;
        break;
     default:
        DIE(aTHX_ "panic: return");
@@ -1828,24 +2048,25 @@ PP(pp_return)
     }
     PL_stack_sp = newsp;
 
+    LEAVE;
     /* Stack values are safe: */
     if (popsub2) {
+       cxstack_ix--;
        POPSUB(cx,sv);  /* release CV and @_ ... */
     }
     else
        sv = Nullsv;
     PL_curpm = newpm;  /* ... and pop $1 et al */
 
-    LEAVE;
     LEAVESUB(sv);
     if (clear_errsv)
-       sv_setpv(ERRSV,"");
-    return pop_return();
+       sv_setpvn(ERRSV,"",0);
+    return retop;
 }
 
 PP(pp_last)
 {
-    dSP;
+    dVAR; dSP;
     I32 cxix;
     register PERL_CONTEXT *cx;
     I32 pop2 = 0;
@@ -1857,6 +2078,7 @@ PP(pp_last)
     SV **mark;
     SV *sv = Nullsv;
 
+
     if (PL_op->op_flags & OPf_SPECIAL) {
        cxix = dopoptoloop(cxstack_ix);
        if (cxix < 0)
@@ -1871,6 +2093,7 @@ PP(pp_last)
        dounwind(cxix);
 
     POPBLOCK(cx,newpm);
+    cxstack_ix++; /* temporarily protect top context */
     mark = newsp;
     switch (CxTYPE(cx)) {
     case CXt_LOOP:
@@ -1880,15 +2103,15 @@ PP(pp_last)
        break;
     case CXt_SUB:
        pop2 = CXt_SUB;
-       nextop = pop_return();
+       nextop = cx->blk_sub.retop;
        break;
     case CXt_EVAL:
        POPEVAL(cx);
-       nextop = pop_return();
+       nextop = cx->blk_eval.retop;
        break;
     case CXt_FORMAT:
        POPFORMAT(cx);
-       nextop = pop_return();
+       nextop = cx->blk_sub.retop;
        break;
     default:
        DIE(aTHX_ "panic: last");
@@ -1912,6 +2135,8 @@ PP(pp_last)
     SP = newsp;
     PUTBACK;
 
+    LEAVE;
+    cxstack_ix--;
     /* Stack values are safe: */
     switch (pop2) {
     case CXt_LOOP:
@@ -1924,13 +2149,15 @@ PP(pp_last)
     }
     PL_curpm = newpm;  /* ... and pop $1 et al */
 
-    LEAVE;
     LEAVESUB(sv);
+    PERL_UNUSED_VAR(optype);
+    PERL_UNUSED_VAR(gimme);
     return nextop;
 }
 
 PP(pp_next)
 {
+    dVAR;
     I32 cxix;
     register PERL_CONTEXT *cx;
     I32 inner;
@@ -1954,14 +2181,17 @@ PP(pp_next)
     TOPBLOCK(cx);
     if (PL_scopestack_ix < inner)
        leave_scope(PL_scopestack[PL_scopestack_ix]);
+    PL_curcop = cx->blk_oldcop;
     return cx->blk_loop.next_op;
 }
 
 PP(pp_redo)
 {
+    dVAR;
     I32 cxix;
     register PERL_CONTEXT *cx;
     I32 oldsave;
+    OP* redo_op;
 
     if (PL_op->op_flags & OPf_SPECIAL) {
        cxix = dopoptoloop(cxstack_ix);
@@ -1976,24 +2206,34 @@ PP(pp_redo)
     if (cxix < cxstack_ix)
        dounwind(cxix);
 
+    redo_op = cxstack[cxix].blk_loop.redo_op;
+    if (redo_op->op_type == OP_ENTER) {
+       /* pop one less context to avoid $x being freed in while (my $x..) */
+       cxstack_ix++;
+       assert(CxTYPE(&cxstack[cxstack_ix]) == CXt_BLOCK);
+       redo_op = redo_op->op_next;
+    }
+
     TOPBLOCK(cx);
     oldsave = PL_scopestack[PL_scopestack_ix - 1];
     LEAVE_SCOPE(oldsave);
-    return cx->blk_loop.redo_op;
+    FREETMPS;
+    PL_curcop = cx->blk_oldcop;
+    return redo_op;
 }
 
 STATIC OP *
-S_dofindlabel(pTHX_ OP *o, char *label, OP **opstack, OP **oplimit)
+S_dofindlabel(pTHX_ OP *o, const char *label, OP **opstack, OP **oplimit)
 {
-    OP *kid = Nullop;
     OP **ops = opstack;
-    static char too_deep[] = "Target of goto is too deeply nested";
+    static const char too_deep[] = "Target of goto is too deeply nested";
 
     if (ops >= oplimit)
        Perl_croak(aTHX_ too_deep);
     if (o->op_type == OP_LEAVE ||
        o->op_type == OP_SCOPE ||
        o->op_type == OP_LEAVELOOP ||
+       o->op_type == OP_LEAVESUB ||
        o->op_type == OP_LEAVETRY)
     {
        *ops++ = cUNOPo->op_first;
@@ -2002,6 +2242,7 @@ S_dofindlabel(pTHX_ OP *o, char *label, OP **opstack, OP **oplimit)
     }
     *ops = 0;
     if (o->op_flags & OPf_KIDS) {
+       OP *kid;
        /* 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) &&
@@ -2011,11 +2252,15 @@ S_dofindlabel(pTHX_ OP *o, char *label, OP **opstack, OP **oplimit)
        for (kid = cUNOPo->op_first; kid; kid = kid->op_sibling) {
            if (kid == PL_lastgotoprobe)
                continue;
-           if ((kid->op_type == OP_NEXTSTATE || kid->op_type == OP_DBSTATE) &&
-               (ops == opstack ||
-                (ops[-1]->op_type != OP_NEXTSTATE &&
-                 ops[-1]->op_type != OP_DBSTATE)))
-               *ops++ = kid;
+           if (kid->op_type == OP_NEXTSTATE || kid->op_type == OP_DBSTATE) {
+               if (ops == opstack)
+                   *ops++ = kid;
+               else if (ops[-1]->op_type == OP_NEXTSTATE ||
+                        ops[-1]->op_type == OP_DBSTATE)
+                   ops[-1] = kid;
+               else
+                   *ops++ = kid;
+           }
            if ((o = dofindlabel(kid, label, ops, oplimit)))
                return o;
        }
@@ -2032,20 +2277,18 @@ PP(pp_dump)
 
 PP(pp_goto)
 {
-    dSP;
+    dVAR; dSP;
     OP *retop = 0;
     I32 ix;
     register PERL_CONTEXT *cx;
 #define GOTO_DEPTH 64
     OP *enterops[GOTO_DEPTH];
-    char *label;
-    int do_dump = (PL_op->op_type == OP_DUMP);
-    static char must_have_label[] = "goto must have label";
+    const char *label = 0;
+    const bool do_dump = (PL_op->op_type == OP_DUMP);
+    static const char must_have_label[] = "goto must have label";
 
-    label = 0;
     if (PL_op->op_flags & OPf_STACKED) {
-       SV *sv = POPs;
-       STRLEN n_a;
+       SV * const sv = POPs;
 
        /* This egregious kludge implements goto &subroutine */
        if (SvROK(sv) && SvTYPE(SvRV(sv)) == SVt_PVCV) {
@@ -2055,12 +2298,13 @@ PP(pp_goto)
            SV** mark;
            I32 items = 0;
            I32 oldsave;
+           bool reified = 0;
 
        retry:
            if (!CvROOT(cv) && !CvXSUB(cv)) {
-               GV *gv = CvGV(cv);
-               GV *autogv;
+               const GV * const gv = CvGV(cv);
                if (gv) {
+                   GV *autogv;
                    SV *tmpstr;
                    /* autoloaded stub? */
                    if (cv != GvCV(gv) && (cv = GvCV(gv)))
@@ -2071,56 +2315,56 @@ PP(pp_goto)
                        goto retry;
                    tmpstr = sv_newmortal();
                    gv_efullname3(tmpstr, gv, Nullch);
-                   DIE(aTHX_ "Goto undefined subroutine &%s",SvPVX(tmpstr));
+                   DIE(aTHX_ "Goto undefined subroutine &%"SVf"",tmpstr);
                }
                DIE(aTHX_ "Goto undefined subroutine");
            }
 
            /* First do some returnish stuff. */
+           (void)SvREFCNT_inc(cv); /* avoid premature free during unwind */
+           FREETMPS;
            cxix = dopoptosub(cxstack_ix);
            if (cxix < 0)
                DIE(aTHX_ "Can't goto subroutine outside a subroutine");
            if (cxix < cxstack_ix)
                dounwind(cxix);
            TOPBLOCK(cx);
-           if (CxREALEVAL(cx))
-               DIE(aTHX_ "Can't goto subroutine from an eval-string");
-           mark = PL_stack_sp;
+           SPAGAIN;
+           /* ban goto in eval: see <20050521150056.GC20213@iabyn.com> */
+           if (CxTYPE(cx) == CXt_EVAL) {
+               if (CxREALEVAL(cx))
+                   DIE(aTHX_ "Can't goto subroutine from an eval-string");
+               else
+                   DIE(aTHX_ "Can't goto subroutine from an eval-block");
+           }
            if (CxTYPE(cx) == CXt_SUB && cx->blk_sub.hasargs) {
                /* put @_ back onto stack */
                AV* av = cx->blk_sub.argarray;
-               
+
                items = AvFILLp(av) + 1;
-               PL_stack_sp++;
-               EXTEND(PL_stack_sp, items); /* @_ could have been extended. */
-               Copy(AvARRAY(av), PL_stack_sp, items, SV*);
-               PL_stack_sp += items;
-#ifndef USE_5005THREADS
+               EXTEND(SP, items+1); /* @_ could have been extended. */
+               Copy(AvARRAY(av), SP + 1, items, SV*);
                SvREFCNT_dec(GvAV(PL_defgv));
                GvAV(PL_defgv) = cx->blk_sub.savearray;
-#endif /* USE_5005THREADS */
+               CLEAR_ARGARRAY(av);
                /* abandon @_ if it got reified */
                if (AvREAL(av)) {
-                   (void)sv_2mortal((SV*)av);  /* delay until return */
+                   reified = 1;
+                   SvREFCNT_dec(av);
                    av = newAV();
                    av_extend(av, items-1);
-                   AvFLAGS(av) = AVf_REIFY;
-                   PL_curpad[0] = (SV*)(cx->blk_sub.argarray = av);
+                   AvREIFY_only(av);
+                   PAD_SVl(0) = (SV*)(cx->blk_sub.argarray = av);
                }
            }
            else if (CvXSUB(cv)) {      /* put GvAV(defgv) back onto stack */
-               AV* av;
-#ifdef USE_5005THREADS
-               av = (AV*)PL_curpad[0];
-#else
-               av = GvAV(PL_defgv);
-#endif
+               AV* const av = GvAV(PL_defgv);
                items = AvFILLp(av) + 1;
-               PL_stack_sp++;
-               EXTEND(PL_stack_sp, items); /* @_ could have been extended. */
-               Copy(AvARRAY(av), PL_stack_sp, items, SV*);
-               PL_stack_sp += items;
+               EXTEND(SP, items+1); /* @_ could have been extended. */
+               Copy(AvARRAY(av), SP + 1, items, SV*);
            }
+           mark = SP;
+           SP += items;
            if (CxTYPE(cx) == CXt_SUB &&
                !(CvDEPTH(cx->blk_sub.cv) = cx->blk_sub.olddepth))
                SvREFCNT_dec(cx->blk_sub.cv);
@@ -2129,7 +2373,14 @@ PP(pp_goto)
 
            /* Now do some callish stuff. */
            SAVETMPS;
+           SAVEFREESV(cv); /* later, undo the 'avoid premature free' hack */
            if (CvXSUB(cv)) {
+               OP* retop = cx->blk_sub.retop;
+               if (reified) {
+                   I32 index;
+                   for (index=0; index<items; index++)
+                       sv_2mortal(SP[-index]);
+               }
 #ifdef PERL_XSUB_OLDSTYLE
                if (CvOLDSTYLE(cv)) {
                    I32 (*fp3)(int,int,int);
@@ -2149,20 +2400,21 @@ PP(pp_goto)
                    SV **newsp;
                    I32 gimme;
 
-                   PL_stack_sp--;              /* There is no cv arg. */
+                   /* XS subs don't have a CxSUB, so pop it */
+                   POPBLOCK(cx, PL_curpm);
                    /* Push a mark for the start of arglist */
                    PUSHMARK(mark);
+                   PUTBACK;
                    (void)(*CvXSUB(cv))(aTHX_ cv);
-                   /* Pop the current context like a decent sub should */
-                   POPBLOCK(cx, PL_curpm);
-                   /* Do _not_ use PUTBACK, keep the XSUB's return stack! */
+                   /* Put these at the bottom since the vars are set but not used */
+                   PERL_UNUSED_VAR(newsp);
+                   PERL_UNUSED_VAR(gimme);
                }
                LEAVE;
-               return pop_return();
+               return retop;
            }
            else {
                AV* padlist = CvPADLIST(cv);
-               SV** svp = AvARRAY(padlist);
                if (CxTYPE(cx) == CXt_EVAL) {
                    PL_in_eval = cx->blk_eval.old_in_eval;
                    PL_eval_root = cx->blk_eval.old_eval_root;
@@ -2171,104 +2423,49 @@ PP(pp_goto)
                }
                cx->blk_sub.cv = cv;
                cx->blk_sub.olddepth = (U16)CvDEPTH(cv);
+
                CvDEPTH(cv)++;
                if (CvDEPTH(cv) < 2)
                    (void)SvREFCNT_inc(cv);
-               else {  /* save temporaries on recursion? */
+               else {
                    if (CvDEPTH(cv) == 100 && ckWARN(WARN_RECURSION))
                        sub_crush_depth(cv);
-                   if (CvDEPTH(cv) > AvFILLp(padlist)) {
-                       AV *newpad = newAV();
-                       SV **oldpad = AvARRAY(svp[CvDEPTH(cv)-1]);
-                       I32 ix = AvFILLp((AV*)svp[1]);
-                       I32 names_fill = AvFILLp((AV*)svp[0]);
-                       svp = AvARRAY(svp[0]);
-                       for ( ;ix > 0; ix--) {
-                           if (names_fill >= ix && svp[ix] != &PL_sv_undef) {
-                               char *name = SvPVX(svp[ix]);
-                               if ((SvFLAGS(svp[ix]) & SVf_FAKE)
-                                   || *name == '&')
-                               {
-                                   /* outer lexical or anon code */
-                                   av_store(newpad, ix,
-                                       SvREFCNT_inc(oldpad[ix]) );
-                               }
-                               else {          /* our own lexical */
-                                   if (*name == '@')
-                                       av_store(newpad, ix, sv = (SV*)newAV());
-                                   else if (*name == '%')
-                                       av_store(newpad, ix, sv = (SV*)newHV());
-                                   else
-                                       av_store(newpad, ix, sv = NEWSV(0,0));
-                                   SvPADMY_on(sv);
-                               }
-                           }
-                           else if (IS_PADGV(oldpad[ix]) || IS_PADCONST(oldpad[ix])) {
-                               av_store(newpad, ix, sv = SvREFCNT_inc(oldpad[ix]));
-                           }
-                           else {
-                               av_store(newpad, ix, sv = NEWSV(0,0));
-                               SvPADTMP_on(sv);
-                           }
-                       }
-                       if (cx->blk_sub.hasargs) {
-                           AV* av = newAV();
-                           av_extend(av, 0);
-                           av_store(newpad, 0, (SV*)av);
-                           AvFLAGS(av) = AVf_REIFY;
-                       }
-                       av_store(padlist, CvDEPTH(cv), (SV*)newpad);
-                       AvFILLp(padlist) = CvDEPTH(cv);
-                       svp = AvARRAY(padlist);
-                   }
+                   pad_push(padlist, CvDEPTH(cv));
                }
-#ifdef USE_5005THREADS
-               if (!cx->blk_sub.hasargs) {
-                   AV* av = (AV*)PL_curpad[0];
-               
-                   items = AvFILLp(av) + 1;
-                   if (items) {
-                       /* Mark is at the end of the stack. */
-                       EXTEND(SP, items);
-                       Copy(AvARRAY(av), SP + 1, items, SV*);
-                       SP += items;
-                       PUTBACK ;               
-                   }
-               }
-#endif /* USE_5005THREADS */           
-               SAVEVPTR(PL_curpad);
-               PL_curpad = AvARRAY((AV*)svp[CvDEPTH(cv)]);
-#ifndef USE_5005THREADS
+               SAVECOMPPAD();
+               PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));
                if (cx->blk_sub.hasargs)
-#endif /* USE_5005THREADS */
                {
-                   AV* av = (AV*)PL_curpad[0];
+                   AV* av = (AV*)PAD_SVl(0);
                    SV** ary;
 
-#ifndef USE_5005THREADS
                    cx->blk_sub.savearray = GvAV(PL_defgv);
                    GvAV(PL_defgv) = (AV*)SvREFCNT_inc(av);
-#endif /* USE_5005THREADS */
-                   cx->blk_sub.oldcurpad = PL_curpad;
+                   CX_CURPAD_SAVE(cx->blk_sub);
                    cx->blk_sub.argarray = av;
-                   ++mark;
 
                    if (items >= AvMAX(av) + 1) {
                        ary = AvALLOC(av);
                        if (AvARRAY(av) != ary) {
                            AvMAX(av) += AvARRAY(av) - AvALLOC(av);
-                           SvPVX(av) = (char*)ary;
+                           SvPV_set(av, (char*)ary);
                        }
                        if (items >= AvMAX(av) + 1) {
                            AvMAX(av) = items - 1;
                            Renew(ary,items+1,SV*);
                            AvALLOC(av) = ary;
-                           SvPVX(av) = (char*)ary;
+                           SvPV_set(av, (char*)ary);
                        }
                    }
+                   ++mark;
                    Copy(mark,AvARRAY(av),items,SV*);
                    AvFILLp(av) = items - 1;
                    assert(!AvREAL(av));
+                   if (reified) {
+                       /* transfer 'ownership' of refcnts to new @_ */
+                       AvREAL_on(av);
+                       AvREIFY_off(av);
+                   }
                    while (items--) {
                        if (*mark)
                            SvTEMP_off(*mark);
@@ -2280,13 +2477,17 @@ PP(pp_goto)
                     * We do not care about using sv to call CV;
                     * it's for informational purposes only.
                     */
-                   SV *sv = GvSV(PL_DBsub);
+                   SV * const sv = GvSV(PL_DBsub);
                    CV *gotocv;
-               
+
+                   save_item(sv);
                    if (PERLDB_SUB_NN) {
-                       SvIVX(sv) = PTR2IV(cv); /* Already upgraded, saved */
+                       const int type = SvTYPE(sv);
+                       if (type < SVt_PVIV && type != SVt_IV)
+                           sv_upgrade(sv, SVt_PVIV);
+                       (void)SvIOK_on(sv);
+                       SvIV_set(sv, PTR2IV(cv)); /* Do it the quickest way */
                    } else {
-                       save_item(sv);
                        gv_efullname3(sv, CvGV(cv), Nullch);
                    }
                    if (  PERLDB_GOTO
@@ -2300,7 +2501,7 @@ PP(pp_goto)
            }
        }
        else {
-           label = SvPV(sv,n_a);
+           label = SvPV_nolen_const(sv);
            if (!(do_dump || *label))
                DIE(aTHX_ must_have_label);
        }
@@ -2315,6 +2516,7 @@ PP(pp_goto)
     if (label && *label) {
        OP *gotoprobe = 0;
        bool leaving_eval = FALSE;
+       bool in_block = FALSE;
         PERL_CONTEXT *last_eval_cx = 0;
 
        /* find label */
@@ -2326,7 +2528,7 @@ PP(pp_goto)
            switch (CxTYPE(cx)) {
            case CXt_EVAL:
                leaving_eval = TRUE;
-                if (CxREALEVAL(cx)) {
+                if (!CxTRYBLOCK(cx)) {
                    gotoprobe = (last_eval_cx ?
                                last_eval_cx->blk_eval.old_eval_root :
                                PL_eval_root);
@@ -2340,9 +2542,10 @@ PP(pp_goto)
            case CXt_SUBST:
                continue;
            case CXt_BLOCK:
-               if (ix)
+               if (ix) {
                    gotoprobe = cx->blk_oldcop->op_sibling;
-               else
+                   in_block = TRUE;
+               } else
                    gotoprobe = PL_main_root;
                break;
            case CXt_SUB:
@@ -2399,7 +2602,8 @@ PP(pp_goto)
 
        if (*enterops && enterops[1]) {
            OP *oldop = PL_op;
-           for (ix = 1; enterops[ix]; ix++) {
+           ix = enterops[1]->op_type == OP_ENTER && in_block ? 2 : 1;
+           for (; enterops[ix]; ix++) {
                PL_op = enterops[ix];
                /* Eventually we may want to stack the needed arguments
                 * for each op.  For now, we punt on the hard ones. */
@@ -2452,7 +2656,7 @@ PP(pp_exit)
 PP(pp_nswitch)
 {
     dSP;
-    NV value = SvNVx(GvSV(cCOP->cop_gv));
+    const NV value = SvNVx(GvSV(cCOP->cop_gv));
     register I32 match = I_32(value);
 
     if (value < 0.0) {
@@ -2476,8 +2680,7 @@ PP(pp_cswitch)
     if (PL_multiline)
        PL_op = PL_op->op_next;                 /* can't assume anything */
     else {
-       STRLEN n_a;
-       match = *(SvPVx(GvSV(cCOP->cop_gv), n_a)) & 255;
+       match = *(SvPVx_nolen_const(GvSV(cCOP->cop_gv))) & 255;
        match -= cCOP->uop.scop.scop_offset;
        if (match < 0)
            match = 0;
@@ -2494,13 +2697,13 @@ PP(pp_cswitch)
 STATIC void
 S_save_lines(pTHX_ AV *array, SV *sv)
 {
-    register char *s = SvPVX(sv);
-    register char *send = SvPVX(sv) + SvCUR(sv);
-    register char *t;
-    register I32 line = 1;
+    const char *s = SvPVX_const(sv);
+    const char * const send = SvPVX_const(sv) + SvCUR(sv);
+    I32 line = 1;
 
     while (s && s < send) {
-       SV *tmpstr = NEWSV(85,0);
+       const char *t;
+       SV * const tmpstr = NEWSV(85,0);
 
        sv_upgrade(tmpstr, SVt_PVMG);
        t = strchr(s, '\n');
@@ -2515,28 +2718,18 @@ S_save_lines(pTHX_ AV *array, SV *sv)
     }
 }
 
-#ifdef PERL_FLEXIBLE_EXCEPTIONS
-STATIC void *
-S_docatch_body(pTHX_ va_list args)
-{
-    return docatch_body();
-}
-#endif
-
-STATIC void *
+STATIC void
 S_docatch_body(pTHX)
 {
     CALLRUNOPS(aTHX);
-    return NULL;
+    return;
 }
 
 STATIC OP *
 S_docatch(pTHX_ OP *o)
 {
     int ret;
-    OP *oldop = PL_op;
-    OP *retop;
-    volatile PERL_SI *cursi = PL_curstackinfo;
+    OP * const oldop = PL_op;
     dJMPENV;
 
 #ifdef DEBUGGING
@@ -2544,37 +2737,32 @@ S_docatch(pTHX_ OP *o)
 #endif
     PL_op = o;
 
-    /* Normally, the leavetry at the end of this block of ops will
-     * pop an op off the return stack and continue there. By setting
-     * the op to Nullop, we force an exit from the inner runops()
-     * loop. DAPM.
-     */
-    retop = pop_return();
-    push_return(Nullop);
-
-#ifdef PERL_FLEXIBLE_EXCEPTIONS
- redo_body:
-    CALLPROTECT(aTHX_ pcur_env, &ret, MEMBER_TO_FPTR(S_docatch_body));
-#else
     JMPENV_PUSH(ret);
-#endif
     switch (ret) {
     case 0:
-#ifndef PERL_FLEXIBLE_EXCEPTIONS
+       assert(cxstack_ix >= 0);
+       assert(CxTYPE(&cxstack[cxstack_ix]) == CXt_EVAL);
+       cxstack[cxstack_ix].blk_eval.cur_top_env = PL_top_env;
  redo_body:
        docatch_body();
-#endif
        break;
     case 3:
        /* die caught by an inner eval - continue inner loop */
-       if (PL_restartop && cursi == PL_curstackinfo) {
+
+       /* NB XXX we rely on the old popped CxEVAL still being at the top
+        * of the stack; the way die_where() currently works, this
+        * assumption is valid. In theory The cur_top_env value should be
+        * returned in another global, the way retop (aka PL_restartop)
+        * is. */
+       assert(CxTYPE(&cxstack[cxstack_ix+1]) == CXt_EVAL);
+
+       if (PL_restartop
+           && cxstack[cxstack_ix+1].blk_eval.cur_top_env == PL_top_env)
+       {
            PL_op = PL_restartop;
            PL_restartop = 0;
            goto redo_body;
        }
-       /* a die in this eval - continue in outer loop */
-       if (!PL_restartop)
-           break;
        /* FALL THROUGH */
     default:
        JMPENV_POP;
@@ -2584,37 +2772,39 @@ S_docatch(pTHX_ OP *o)
     }
     JMPENV_POP;
     PL_op = oldop;
-    return retop;
+    return Nullop;
 }
 
 OP *
-Perl_sv_compile_2op(pTHX_ SV *sv, OP** startop, char *code, AV** avp)
+Perl_sv_compile_2op(pTHX_ SV *sv, OP** startop, const char *code, PAD** padp)
 /* sv Text to convert to OP tree. */
 /* startop op_free() this to undo. */
 /* code Short string id of the caller. */
 {
-    dSP;                               /* Make POPBLOCK work. */
+    dVAR; dSP;                         /* Make POPBLOCK work. */
     PERL_CONTEXT *cx;
     SV **newsp;
-    I32 gimme = 0;   /* SUSPECT - INITIALZE TO WHAT?  NI-S */
+    I32 gimme = G_VOID;
     I32 optype;
     OP dummy;
     OP *rop;
     char tbuf[TYPE_DIGITS(long) + 12 + 10];
     char *tmpbuf = tbuf;
     char *safestr;
+    int runtime;
+    CV* runcv = Nullcv;        /* initialise to avoid compiler warnings */
 
     ENTER;
     lex_start(sv);
     SAVETMPS;
     /* switch to eval mode */
 
-    if (PL_curcop == &PL_compiling) {
+    if (IN_PERL_COMPILETIME) {
        SAVECOPSTASH_FREE(&PL_compiling);
        CopSTASH_set(&PL_compiling, PL_curstash);
     }
     if (PERLDB_NAMEEVAL && CopLINE(PL_curcop)) {
-       SV *sv = sv_newmortal();
+       SV * const sv = sv_newmortal();
        Perl_sv_setpvf(aTHX_ sv, "_<(%.10seval %lu)[%s:%"IVdf"]",
                       code, (unsigned long)++PL_evalseq,
                       CopFILE(PL_curcop), (IV)CopLINE(PL_curcop));
@@ -2639,39 +2829,95 @@ Perl_sv_compile_2op(pTHX_ SV *sv, OP** startop, char *code, AV** avp)
 #else
     SAVEVPTR(PL_op);
 #endif
-    PL_hints &= HINT_UTF8;
+
+    /* we get here either during compilation, or via pp_regcomp at runtime */
+    runtime = IN_PERL_RUNTIME;
+    if (runtime)
+       runcv = find_runcv(NULL);
 
     PL_op = &dummy;
     PL_op->op_type = OP_ENTEREVAL;
     PL_op->op_flags = 0;                       /* Avoid uninit warning. */
-    PUSHBLOCK(cx, CXt_EVAL|(PL_curcop == &PL_compiling ? 0 : CXp_REAL), SP);
+    PUSHBLOCK(cx, CXt_EVAL|(IN_PERL_COMPILETIME ? 0 : CXp_REAL), SP);
     PUSHEVAL(cx, 0, Nullgv);
-    rop = doeval(G_SCALAR, startop);
+
+    if (runtime)
+       rop = doeval(G_SCALAR, startop, runcv, PL_curcop->cop_seq);
+    else
+       rop = doeval(G_SCALAR, startop, PL_compcv, PL_cop_seqmax);
     POPBLOCK(cx,PL_curpm);
     POPEVAL(cx);
 
     (*startop)->op_type = OP_NULL;
     (*startop)->op_ppaddr = PL_ppaddr[OP_NULL];
     lex_end();
-    *avp = (AV*)SvREFCNT_inc(PL_comppad);
+    /* XXX DAPM do this properly one year */
+    *padp = (AV*)SvREFCNT_inc(PL_comppad);
     LEAVE;
-    if (PL_curcop == &PL_compiling)
+    if (IN_PERL_COMPILETIME)
        PL_compiling.op_private = (U8)(PL_hints & HINT_PRIVATE_MASK);
 #ifdef OP_IN_REGISTER
     op = PL_opsave;
 #endif
+    PERL_UNUSED_VAR(newsp);
+    PERL_UNUSED_VAR(optype);
+
     return rop;
 }
 
+
+/*
+=for apidoc find_runcv
+
+Locate the CV corresponding to the currently executing sub or eval.
+If db_seqp is non_null, skip CVs that are in the DB package and populate
+*db_seqp with the cop sequence number at the point that the DB:: code was
+entered. (allows debuggers to eval in the scope of the breakpoint rather
+than in the scope of the debugger itself).
+
+=cut
+*/
+
+CV*
+Perl_find_runcv(pTHX_ U32 *db_seqp)
+{
+    PERL_SI     *si;
+
+    if (db_seqp)
+       *db_seqp = PL_curcop->cop_seq;
+    for (si = PL_curstackinfo; si; si = si->si_prev) {
+        I32 ix;
+       for (ix = si->si_cxix; ix >= 0; ix--) {
+           const PERL_CONTEXT *cx = &(si->si_cxstack[ix]);
+           if (CxTYPE(cx) == CXt_SUB || CxTYPE(cx) == CXt_FORMAT) {
+               CV * const cv = cx->blk_sub.cv;
+               /* skip DB:: code */
+               if (db_seqp && PL_debstash && CvSTASH(cv) == PL_debstash) {
+                   *db_seqp = cx->blk_oldcop->cop_seq;
+                   continue;
+               }
+               return cv;
+           }
+           else if (CxTYPE(cx) == CXt_EVAL && !CxTRYBLOCK(cx))
+               return PL_compcv;
+       }
+    }
+    return PL_main_cv;
+}
+
+
+/* Compile a require/do, an eval '', or a /(?{...})/.
+ * In the last case, startop is non-null, and contains the address of
+ * a pointer that should be set to the just-compiled code.
+ * outside is the lexically enclosing CV (if any) that invoked us.
+ */
+
 /* With USE_5005THREADS, eval_owner must be held on entry to doeval */
 STATIC OP *
-S_doeval(pTHX_ int gimme, OP** startop)
+S_doeval(pTHX_ int gimme, OP** startop, CV* outside, U32 seq)
 {
-    dSP;
-    OP *saveop = PL_op;
-    CV *caller;
-    AV* comppadlist;
-    I32 i;
+    dVAR; dSP;
+    OP * const saveop = PL_op;
 
     PL_in_eval = ((saveop && saveop->op_type == OP_REQUIRE)
                  ? (EVAL_INREQUIRE | (PL_in_eval & EVAL_INEVAL))
@@ -2679,27 +2925,6 @@ S_doeval(pTHX_ int gimme, OP** startop)
 
     PUSHMARK(SP);
 
-    /* set up a scratch pad */
-
-    SAVEI32(PL_padix);
-    SAVEVPTR(PL_curpad);
-    SAVESPTR(PL_comppad);
-    SAVESPTR(PL_comppad_name);
-    SAVEI32(PL_comppad_name_fill);
-    SAVEI32(PL_min_intro_pending);
-    SAVEI32(PL_max_intro_pending);
-
-    caller = PL_compcv;
-    for (i = cxstack_ix - 1; i >= 0; i--) {
-       PERL_CONTEXT *cx = &cxstack[i];
-       if (CxTYPE(cx) == CXt_EVAL)
-           break;
-       else if (CxTYPE(cx) == CXt_SUB || CxTYPE(cx) == CXt_FORMAT) {
-           caller = cx->blk_sub.cv;
-           break;
-       }
-    }
-
     SAVESPTR(PL_compcv);
     PL_compcv = (CV*)NEWSV(1104,0);
     sv_upgrade((SV *)PL_compcv, SVt_PVCV);
@@ -2707,36 +2932,13 @@ S_doeval(pTHX_ int gimme, OP** startop)
     assert(CxTYPE(&cxstack[cxstack_ix]) == CXt_EVAL);
     cxstack[cxstack_ix].blk_eval.cv = PL_compcv;
 
-#ifdef USE_5005THREADS
-    CvOWNER(PL_compcv) = 0;
-    New(666, CvMUTEXP(PL_compcv), 1, perl_mutex);
-    MUTEX_INIT(CvMUTEXP(PL_compcv));
-#endif /* USE_5005THREADS */
-
-    PL_comppad = newAV();
-    av_push(PL_comppad, Nullsv);
-    PL_curpad = AvARRAY(PL_comppad);
-    PL_comppad_name = newAV();
-    PL_comppad_name_fill = 0;
-    PL_min_intro_pending = 0;
-    PL_padix = 0;
-#ifdef USE_5005THREADS
-    av_store(PL_comppad_name, 0, newSVpvn("@_", 2));
-    PL_curpad[0] = (SV*)newAV();
-    SvPADMY_on(PL_curpad[0]);  /* XXX Needed? */
-#endif /* USE_5005THREADS */
-
-    comppadlist = newAV();
-    AvREAL_off(comppadlist);
-    av_store(comppadlist, 0, (SV*)PL_comppad_name);
-    av_store(comppadlist, 1, (SV*)PL_comppad);
-    CvPADLIST(PL_compcv) = comppadlist;
-
-    if (!saveop ||
-       (saveop->op_type != OP_REQUIRE && saveop->op_type != OP_DOFILE))
-    {
-       CvOUTSIDE(PL_compcv) = (CV*)SvREFCNT_inc(caller);
-    }
+    CvOUTSIDE_SEQ(PL_compcv) = seq;
+    CvOUTSIDE(PL_compcv) = (CV*)SvREFCNT_inc(outside);
+
+    /* set up a scratch pad */
+
+    CvPADLIST(PL_compcv) = pad_new(padnew_SAVE);
+
 
     SAVEMORTALIZESV(PL_compcv);        /* must remain until end of current statement */
 
@@ -2760,14 +2962,13 @@ S_doeval(pTHX_ int gimme, OP** startop)
     if (saveop && saveop->op_flags & OPf_SPECIAL)
        PL_in_eval |= EVAL_KEEPERR;
     else
-       sv_setpv(ERRSV,"");
+       sv_setpvn(ERRSV,"",0);
     if (yyparse() || PL_error_count || !PL_eval_root) {
-       SV **newsp;
-       I32 gimme;
-       PERL_CONTEXT *cx;
+       SV **newsp;                     /* Used by POPBLOCK. */
+       PERL_CONTEXT *cx = &cxstack[cxstack_ix];
        I32 optype = 0;                 /* Might be reset by POPEVAL. */
-       STRLEN n_a;
-       
+       const char *msg;
+
        PL_op = saveop;
        if (PL_eval_root) {
            op_free(PL_eval_root);
@@ -2777,39 +2978,47 @@ S_doeval(pTHX_ int gimme, OP** startop)
        if (!startop) {
            POPBLOCK(cx,PL_curpm);
            POPEVAL(cx);
-           pop_return();
        }
        lex_end();
        LEAVE;
+
+       msg = SvPVx_nolen_const(ERRSV);
        if (optype == OP_REQUIRE) {
-           char* msg = SvPVx(ERRSV, n_a);
+           const SV * const nsv = cx->blk_eval.old_namesv;
+           (void)hv_store(GvHVn(PL_incgv), SvPVX_const(nsv), SvCUR(nsv),
+                          &PL_sv_undef, 0);
            DIE(aTHX_ "%sCompilation failed in require",
                *msg ? msg : "Unknown error\n");
        }
        else if (startop) {
-           char* msg = SvPVx(ERRSV, n_a);
-
            POPBLOCK(cx,PL_curpm);
            POPEVAL(cx);
            Perl_croak(aTHX_ "%sCompilation failed in regexp",
                       (*msg ? msg : "Unknown error\n"));
        }
-#ifdef USE_5005THREADS
-       MUTEX_LOCK(&PL_eval_mutex);
-       PL_eval_owner = 0;
-       COND_SIGNAL(&PL_eval_cond);
-       MUTEX_UNLOCK(&PL_eval_mutex);
-#endif /* USE_5005THREADS */
+       else {
+           if (!*msg) {
+               sv_setpv(ERRSV, "Compilation error");
+           }
+       }
+       PERL_UNUSED_VAR(newsp);
        RETPUSHUNDEF;
     }
     CopLINE_set(&PL_compiling, 0);
     if (startop) {
        *startop = PL_eval_root;
-       SvREFCNT_dec(CvOUTSIDE(PL_compcv));
-       CvOUTSIDE(PL_compcv) = Nullcv;
     } else
        SAVEFREEOP(PL_eval_root);
-    if (gimme & G_VOID)
+
+    /* Set the context for this new optree.
+     * If the last op is an OP_REQUIRE, force scalar context.
+     * Otherwise, propagate the context from the eval(). */
+    if (PL_eval_root->op_type == OP_LEAVEEVAL
+           && cUNOPx(PL_eval_root)->op_first->op_type == OP_LINESEQ
+           && cLISTOPx(cUNOPx(PL_eval_root)->op_first)->op_last->op_type
+           == OP_REQUIRE)
+       scalar(PL_eval_root);
+    else if (gimme & G_VOID)
        scalarvoid(PL_eval_root);
     else if (gimme & G_ARRAY)
        list(PL_eval_root);
@@ -2820,7 +3029,7 @@ S_doeval(pTHX_ int gimme, OP** startop)
 
     /* Register with debugger: */
     if (PERLDB_INTER && saveop->op_type == OP_REQUIRE) {
-       CV *cv = get_cv("DB::postponed", FALSE);
+       CV * const cv = get_cv("DB::postponed", FALSE);
        if (cv) {
            dSP;
            PUSHMARK(SP);
@@ -2836,31 +3045,26 @@ S_doeval(pTHX_ int gimme, OP** startop)
     SP = PL_stack_base + POPMARK;              /* pop original mark */
     PL_op = saveop;                    /* The caller may need it. */
     PL_lex_state = LEX_NOTPARSING;     /* $^S needs this. */
-#ifdef USE_5005THREADS
-    MUTEX_LOCK(&PL_eval_mutex);
-    PL_eval_owner = 0;
-    COND_SIGNAL(&PL_eval_cond);
-    MUTEX_UNLOCK(&PL_eval_mutex);
-#endif /* USE_5005THREADS */
 
     RETURNOP(PL_eval_start);
 }
 
 STATIC PerlIO *
-S_doopen_pmc(pTHX_ const char *name, const char *mode)
+S_doopen_pm(pTHX_ const char *name, const char *mode)
 {
-    STRLEN namelen = strlen(name);
+#ifndef PERL_DISABLE_PMC
+    const STRLEN namelen = strlen(name);
     PerlIO *fp;
 
     if (namelen > 3 && strEQ(name + namelen - 3, ".pm")) {
-       SV *pmcsv = Perl_newSVpvf(aTHX_ "%s%c", name, 'c');
-       char *pmc = SvPV_nolen(pmcsv);
-       Stat_t pmstat;
+       SV * const pmcsv = Perl_newSVpvf(aTHX_ "%s%c", name, 'c');
+       const char * const pmc = SvPV_nolen_const(pmcsv);
        Stat_t pmcstat;
        if (PerlLIO_stat(pmc, &pmcstat) < 0) {
            fp = PerlIO_open(name, mode);
        }
        else {
+           Stat_t pmstat;
            if (PerlLIO_stat(name, &pmstat) < 0 ||
                pmstat.st_mtime < pmcstat.st_mtime)
            {
@@ -2876,21 +3080,22 @@ S_doopen_pmc(pTHX_ const char *name, const char *mode)
        fp = PerlIO_open(name, mode);
     }
     return fp;
+#else
+    return PerlIO_open(name, mode);
+#endif /* !PERL_DISABLE_PMC */
 }
 
 PP(pp_require)
 {
-    dSP;
+    dVAR; dSP;
     register PERL_CONTEXT *cx;
     SV *sv;
-    char *name;
+    const char *name;
     STRLEN len;
-    char *tryname = Nullch;
+    const char *tryname = Nullch;
     SV *namesv = Nullsv;
-    SV** svp;
-    I32 gimme = GIMME_V;
+    const I32 gimme = GIMME_V;
     PerlIO *tryrsfp = 0;
-    STRLEN n_a;
     int filter_has_file = 0;
     GV *filter_child_proc = 0;
     SV *filter_state = 0;
@@ -2900,81 +3105,46 @@ PP(pp_require)
     OP *op;
 
     sv = POPs;
-    if (SvNIOKp(sv) && PL_op->op_type != OP_DOFILE) {
-       if (SvPOK(sv) && SvNOK(sv) && SvNV(sv)) {               /* require v5.6.1 */
-           UV rev = 0, ver = 0, sver = 0;
-           STRLEN len;
-           U8 *s = (U8*)SvPVX(sv);
-           U8 *end = (U8*)SvPVX(sv) + SvCUR(sv);
-           if (s < end) {
-               rev = utf8n_to_uvchr(s, end - s, &len, 0);
-               s += len;
-               if (s < end) {
-                   ver = utf8n_to_uvchr(s, end - s, &len, 0);
-                   s += len;
-                   if (s < end)
-                       sver = utf8n_to_uvchr(s, end - s, &len, 0);
-               }
-           }
-           if (PERL_REVISION < rev
-               || (PERL_REVISION == rev
-                   && (PERL_VERSION < ver
-                       || (PERL_VERSION == ver
-                           && PERL_SUBVERSION < sver))))
-           {
-               DIE(aTHX_ "Perl v%"UVuf".%"UVuf".%"UVuf" required--this is only "
-                   "v%d.%d.%d, stopped", rev, ver, sver, PERL_REVISION,
-                   PERL_VERSION, PERL_SUBVERSION);
-           }
-           if (ckWARN(WARN_PORTABLE))
+    if ( (SvNIOKp(sv) || SvVOK(sv)) && PL_op->op_type != OP_DOFILE) {
+       if ( SvVOK(sv) && ckWARN(WARN_PORTABLE) )       /* require v5.6.1 */
                Perl_warner(aTHX_ packWARN(WARN_PORTABLE),
                         "v-string in use/require non-portable");
-           RETPUSHYES;
+
+       sv = new_version(sv);
+       if (!sv_derived_from(PL_patchlevel, "version"))
+           (void *)upg_version(PL_patchlevel);
+       if (cUNOP->op_first->op_type == OP_CONST && cUNOP->op_first->op_private & OPpCONST_NOVER) {
+           if ( vcmp(sv,PL_patchlevel) < 0 )
+               DIE(aTHX_ "Perls since %"SVf" too modern--this is %"SVf", stopped",
+                   vnormal(sv), vnormal(PL_patchlevel));
        }
-       else if (!SvPOKp(sv)) {                 /* require 5.005_03 */
-           if ((NV)PERL_REVISION + ((NV)PERL_VERSION/(NV)1000)
-               + ((NV)PERL_SUBVERSION/(NV)1000000)
-               + 0.00000099 < SvNV(sv))
-           {
-               NV nrev = SvNV(sv);
-               UV rev = (UV)nrev;
-               NV nver = (nrev - rev) * 1000;
-               UV ver = (UV)(nver + 0.0009);
-               NV nsver = (nver - ver) * 1000;
-               UV sver = (UV)(nsver + 0.0009);
-
-               /* help out with the "use 5.6" confusion */
-               if (sver == 0 && (rev > 5 || (rev == 5 && ver >= 100))) {
-                   DIE(aTHX_ "Perl v%"UVuf".%"UVuf".%"UVuf" required"
-                       " (did you mean v%"UVuf".%03"UVuf"?)--"
-                       "this is only v%d.%d.%d, stopped",
-                       rev, ver, sver, rev, ver/100,
-                       PERL_REVISION, PERL_VERSION, PERL_SUBVERSION);
-               }
-               else {
-                   DIE(aTHX_ "Perl v%"UVuf".%"UVuf".%"UVuf" required--"
-                       "this is only v%d.%d.%d, stopped",
-                       rev, ver, sver, PERL_REVISION, PERL_VERSION,
-                       PERL_SUBVERSION);
-               }
-           }
-           RETPUSHYES;
+       else {
+           if ( vcmp(sv,PL_patchlevel) > 0 )
+               DIE(aTHX_ "Perl %"SVf" required--this is only %"SVf", stopped",
+                   vnormal(sv), vnormal(PL_patchlevel));
        }
+
+           RETPUSHYES;
     }
-    name = SvPV(sv, len);
+    name = SvPV_const(sv, len);
     if (!(name && len > 0 && *name))
        DIE(aTHX_ "Null filename used");
     TAINT_PROPER("require");
-    if (PL_op->op_type == OP_REQUIRE &&
-      (svp = hv_fetch(GvHVn(PL_incgv), name, len, 0)) &&
-      *svp != &PL_sv_undef)
-       RETPUSHYES;
+    if (PL_op->op_type == OP_REQUIRE) {
+       SV ** const svp = hv_fetch(GvHVn(PL_incgv), name, len, 0);
+       if ( svp ) {
+           if (*svp != &PL_sv_undef)
+               RETPUSHYES;
+           else
+               DIE(aTHX_ "Compilation failed in require");
+       }
+    }
 
     /* prepare to compile file */
 
     if (path_is_absolute(name)) {
        tryname = name;
-       tryrsfp = doopen_pmc(name,PERL_SCRIPT_MODE);
+       tryrsfp = doopen_pm(name,PERL_SCRIPT_MODE);
     }
 #ifdef MACOS_TRADITIONAL
     if (!tryrsfp) {
@@ -2983,12 +3153,12 @@ PP(pp_require)
        MacPerl_CanonDir(name, newname, 1);
        if (path_is_absolute(newname)) {
            tryname = newname;
-           tryrsfp = doopen_pmc(newname,PERL_SCRIPT_MODE);
+           tryrsfp = doopen_pm(newname,PERL_SCRIPT_MODE);
        }
     }
 #endif
     if (!tryrsfp) {
-       AV *ar = GvAVn(PL_incgv);
+       AV * const ar = GvAVn(PL_incgv);
        I32 i;
 #ifdef VMS
        char *unixname;
@@ -3011,7 +3181,7 @@ PP(pp_require)
 
                    Perl_sv_setpvf(aTHX_ namesv, "/loader/0x%"UVxf"/%s",
                                   PTR2UV(SvRV(dirsv)), name);
-                   tryname = SvPVX(namesv);
+                   tryname = SvPVX_const(namesv);
                    tryrsfp = 0;
 
                    ENTER;
@@ -3084,6 +3254,7 @@ PP(pp_require)
                                                      PERL_SCRIPT_MODE);
                            }
                        }
+                       SP--;
                    }
 
                    PUTBACK;
@@ -3118,7 +3289,7 @@ PP(pp_require)
                        || (*name == ':' && name[1] != ':' && strchr(name+2, ':'))
 #endif
                  ) {
-                   char *dir = SvPVx(dirsv, n_a);
+                   const char *dir = SvPVx_nolen_const(dirsv);
 #ifdef MACOS_TRADITIONAL
                    char buf1[256];
                    char buf2[256];
@@ -3126,19 +3297,33 @@ PP(pp_require)
                    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, Nullch)) == Nullch)
                        continue;
                    sv_setpv(namesv, unixdir);
                    sv_catpv(namesv, unixname);
-#else
+#  else
+#    ifdef __SYMBIAN32__
+                   if (PL_origfilename[0] &&
+                       PL_origfilename[1] == ':' &&
+                       !(dir[0] && dir[1] == ':'))
+                       Perl_sv_setpvf(aTHX_ namesv,
+                                      "%c:%s\\%s",
+                                      PL_origfilename[0],
+                                      dir, name);
+                   else
+                       Perl_sv_setpvf(aTHX_ namesv,
+                                      "%s\\%s",
+                                      dir, name);
+#    else
                    Perl_sv_setpvf(aTHX_ namesv, "%s/%s", dir, name);
-#endif
+#    endif
+#  endif
 #endif
                    TAINT_PROPER("require");
-                   tryname = SvPVX(namesv);
-                   tryrsfp = doopen_pmc(tryname, PERL_SCRIPT_MODE);
+                   tryname = SvPVX_const(namesv);
+                   tryrsfp = doopen_pm(tryname, PERL_SCRIPT_MODE);
                    if (tryrsfp) {
                        if (tryname[0] == '.' && tryname[1] == '/')
                            tryname += 2;
@@ -3154,26 +3339,33 @@ PP(pp_require)
     SvREFCNT_dec(namesv);
     if (!tryrsfp) {
        if (PL_op->op_type == OP_REQUIRE) {
-           char *msgstr = name;
-           if (namesv) {                       /* did we lookup @INC? */
-               SV *msg = sv_2mortal(newSVpv(msgstr,0));
-               SV *dirmsgsv = NEWSV(0, 0);
-               AV *ar = GvAVn(PL_incgv);
-               I32 i;
-               sv_catpvn(msg, " in @INC", 8);
-               if (instr(SvPVX(msg), ".h "))
-                   sv_catpv(msg, " (change .h to .ph maybe?)");
-               if (instr(SvPVX(msg), ".ph "))
-                   sv_catpv(msg, " (did you run h2ph?)");
-               sv_catpv(msg, " (@INC contains:");
-               for (i = 0; i <= AvFILL(ar); i++) {
-                   char *dir = SvPVx(*av_fetch(ar, i, TRUE), n_a);
-                   Perl_sv_setpvf(aTHX_ dirmsgsv, " %s", dir);
-                   sv_catsv(msg, dirmsgsv);
-               }
-               sv_catpvn(msg, ")", 1);
-               SvREFCNT_dec(dirmsgsv);
-               msgstr = SvPV_nolen(msg);
+           const char *msgstr = name;
+           if(errno == EMFILE) {
+               SV * const msg = sv_2mortal(newSVpv(msgstr,0));
+               sv_catpv(msg, ":  "); 
+               sv_catpv(msg, Strerror(errno));
+               msgstr = SvPV_nolen_const(msg);
+           } else {
+               if (namesv) {                   /* did we lookup @INC? */
+                   SV * const msg = sv_2mortal(newSVpv(msgstr,0));
+                   SV * const dirmsgsv = NEWSV(0, 0);
+                   AV * const ar = GvAVn(PL_incgv);
+                   I32 i;
+                   sv_catpvn(msg, " in @INC", 8);
+                   if (instr(SvPVX_const(msg), ".h "))
+                       sv_catpv(msg, " (change .h to .ph maybe?)");
+                   if (instr(SvPVX_const(msg), ".ph "))
+                       sv_catpv(msg, " (did you run h2ph?)");
+                   sv_catpv(msg, " (@INC contains:");
+                   for (i = 0; i <= AvFILL(ar); i++) {
+                       const char *dir = SvPVx_nolen_const(*av_fetch(ar, i, TRUE));
+                       Perl_sv_setpvf(aTHX_ dirmsgsv, " %s", dir);
+                       sv_catsv(msg, dirmsgsv);
+                   }
+                   sv_catpvn(msg, ")", 1);
+                   SvREFCNT_dec(dirmsgsv);
+                   msgstr = SvPV_nolen_const(msg);
+               }    
            }
            DIE(aTHX_ "Can't locate %s", msgstr);
        }
@@ -3181,16 +3373,17 @@ PP(pp_require)
        RETPUSHUNDEF;
     }
     else
-       SETERRNO(0, SS$_NORMAL);
+       SETERRNO(0, SS_NORMAL);
 
     /* Assume success here to prevent recursive requirement. */
     len = strlen(name);
     /* Check whether a hook in @INC has already filled %INC */
-    if (!hook_sv || !(svp = hv_fetch(GvHVn(PL_incgv), name, len, 0))) {
-       (void)hv_store(GvHVn(PL_incgv), name, len,
-                      (hook_sv ? SvREFCNT_inc(hook_sv)
-                               : newSVpv(CopFILE(&PL_compiling), 0)),
-                      0 );
+    if (!hook_sv) {
+       (void)hv_store(GvHVn(PL_incgv), name, len, newSVpv(CopFILE(&PL_compiling),0),0);
+    } else {
+       SV** const svp = hv_fetch(GvHVn(PL_incgv), name, len, 0);
+       if (!svp)
+           (void)hv_store(GvHVn(PL_incgv), name, len, SvREFCNT_inc(hook_sv), 0 );
     }
 
     ENTER;
@@ -3215,7 +3408,7 @@ PP(pp_require)
     PL_compiling.cop_io = Nullsv;
 
     if (filter_sub || filter_child_proc) {
-       SV *datasv = filter_add(run_user_filter, Nullsv);
+       SV * const datasv = filter_add(run_user_filter, Nullsv);
        IoLINES(datasv) = filter_has_file;
        IoFMT_GV(datasv) = (GV *)filter_child_proc;
        IoTOP_GV(datasv) = (GV *)filter_state;
@@ -3223,29 +3416,21 @@ PP(pp_require)
     }
 
     /* switch to eval mode */
-    push_return(PL_op->op_next);
     PUSHBLOCK(cx, CXt_EVAL, SP);
     PUSHEVAL(cx, name, Nullgv);
+    cx->blk_eval.retop = PL_op->op_next;
 
     SAVECOPLINE(&PL_compiling);
     CopLINE_set(&PL_compiling, 0);
 
     PUTBACK;
-#ifdef USE_5005THREADS
-    MUTEX_LOCK(&PL_eval_mutex);
-    if (PL_eval_owner && PL_eval_owner != thr)
-       while (PL_eval_owner)
-           COND_WAIT(&PL_eval_cond, &PL_eval_mutex);
-    PL_eval_owner = thr;
-    MUTEX_UNLOCK(&PL_eval_mutex);
-#endif /* USE_5005THREADS */
 
     /* Store and reset encoding. */
     encoding = PL_encoding;
     PL_encoding = Nullsv;
 
-    op = DOCATCH(doeval(gimme, NULL));
-    
+    op = DOCATCH(doeval(gimme, NULL, Nullcv, PL_curcop->cop_seq));
+
     /* Restore encoding. */
     PL_encoding = encoding;
 
@@ -3259,17 +3444,20 @@ PP(pp_dofile)
 
 PP(pp_entereval)
 {
-    dSP;
+    dVAR; dSP;
     register PERL_CONTEXT *cx;
     dPOPss;
-    I32 gimme = GIMME_V, was = PL_sub_generation;
+    const I32 gimme = GIMME_V;
+    const I32 was = PL_sub_generation;
     char tbuf[TYPE_DIGITS(long) + 12];
     char *tmpbuf = tbuf;
     char *safestr;
     STRLEN len;
     OP *ret;
+    CV* runcv;
+    U32 seq;
 
-    if (!SvPV(sv,len) || !len)
+    if (!SvPV_const(sv,len))
        RETPUSHUNDEF;
     TAINT_PROPER("eval");
 
@@ -3280,7 +3468,7 @@ PP(pp_entereval)
     /* switch to eval mode */
 
     if (PERLDB_NAMEEVAL && CopLINE(PL_curcop)) {
-       SV *sv = sv_newmortal();
+       SV * const sv = sv_newmortal();
        Perl_sv_setpvf(aTHX_ sv, "_<(eval %lu)[%s:%"IVdf"]",
                       (unsigned long)++PL_evalseq,
                       CopFILE(PL_curcop), (IV)CopLINE(PL_curcop));
@@ -3315,25 +3503,23 @@ PP(pp_entereval)
         PL_compiling.cop_io = newSVsv(PL_curcop->cop_io);
         SAVEFREESV(PL_compiling.cop_io);
     }
+    /* special case: an eval '' executed within the DB package gets lexically
+     * placed in the first non-DB CV rather than the current CV - this
+     * allows the debugger to execute code, find lexicals etc, in the
+     * scope of the code being debugged. Passing &seq gets find_runcv
+     * to do the dirty work for us */
+    runcv = find_runcv(&seq);
 
-    push_return(PL_op->op_next);
     PUSHBLOCK(cx, (CXt_EVAL|CXp_REAL), SP);
     PUSHEVAL(cx, 0, Nullgv);
+    cx->blk_eval.retop = PL_op->op_next;
 
     /* prepare to compile string */
 
     if (PERLDB_LINE && PL_curstash != PL_debstash)
        save_lines(CopFILEAV(&PL_compiling), PL_linestr);
     PUTBACK;
-#ifdef USE_5005THREADS
-    MUTEX_LOCK(&PL_eval_mutex);
-    if (PL_eval_owner && PL_eval_owner != thr)
-       while (PL_eval_owner)
-           COND_WAIT(&PL_eval_cond, &PL_eval_mutex);
-    PL_eval_owner = thr;
-    MUTEX_UNLOCK(&PL_eval_mutex);
-#endif /* USE_5005THREADS */
-    ret = doeval(gimme, NULL);
+    ret = doeval(gimme, NULL, runcv, seq);
     if (PERLDB_INTER && was != (I32)PL_sub_generation /* Some subs defined here. */
        && ret != PL_op->op_next) {     /* Successive compilation. */
        strcpy(safestr, "_<(eval )");   /* Anything fake and short. */
@@ -3343,19 +3529,19 @@ PP(pp_entereval)
 
 PP(pp_leaveeval)
 {
-    dSP;
+    dVAR; dSP;
     register SV **mark;
     SV **newsp;
     PMOP *newpm;
     I32 gimme;
     register PERL_CONTEXT *cx;
     OP *retop;
-    U8 save_flags = PL_op -> op_flags;
+    const U8 save_flags = PL_op -> op_flags;
     I32 optype;
 
     POPBLOCK(cx,newpm);
     POPEVAL(cx);
-    retop = pop_return();
+    retop = cx->blk_eval.retop;
 
     TAINT_NOT;
     if (gimme == G_VOID)
@@ -3395,15 +3581,15 @@ PP(pp_leaveeval)
        !(gimme == G_SCALAR ? SvTRUE(*SP) : SP > newsp))
     {
        /* Unassume the success we assumed earlier. */
-       SV *nsv = cx->blk_eval.old_namesv;
-       (void)hv_delete(GvHVn(PL_incgv), SvPVX(nsv), SvCUR(nsv), G_DISCARD);
-       retop = Perl_die(aTHX_ "%s did not return a true value", SvPVX(nsv));
+       SV * const nsv = cx->blk_eval.old_namesv;
+       (void)hv_delete(GvHVn(PL_incgv), SvPVX_const(nsv), SvCUR(nsv), G_DISCARD);
+       retop = Perl_die(aTHX_ "%"SVf" did not return a true value", nsv);
        /* die_where() did LEAVE, or we won't be here */
     }
     else {
        LEAVE;
        if (!(save_flags & OPf_SPECIAL))
-           sv_setpv(ERRSV,"");
+           sv_setpvn(ERRSV,"",0);
     }
 
     RETURNOP(retop);
@@ -3411,37 +3597,36 @@ PP(pp_leaveeval)
 
 PP(pp_entertry)
 {
-    dSP;
+    dVAR; dSP;
     register PERL_CONTEXT *cx;
-    I32 gimme = GIMME_V;
+    const I32 gimme = GIMME_V;
 
     ENTER;
     SAVETMPS;
 
-    push_return(cLOGOP->op_other->op_next);
     PUSHBLOCK(cx, (CXt_EVAL|CXp_TRYBLOCK), SP);
     PUSHEVAL(cx, 0, 0);
+    cx->blk_eval.retop = cLOGOP->op_other->op_next;
 
     PL_in_eval = EVAL_INEVAL;
-    sv_setpv(ERRSV,"");
+    sv_setpvn(ERRSV,"",0);
     PUTBACK;
     return DOCATCH(PL_op->op_next);
 }
 
 PP(pp_leavetry)
 {
-    dSP;
+    dVAR; dSP;
     register SV **mark;
     SV **newsp;
     PMOP *newpm;
-    OP* retop;
     I32 gimme;
     register PERL_CONTEXT *cx;
     I32 optype;
 
     POPBLOCK(cx,newpm);
     POPEVAL(cx);
-    retop = pop_return();
+    PERL_UNUSED_VAR(optype);
 
     TAINT_NOT;
     if (gimme == G_VOID)
@@ -3472,11 +3657,11 @@ PP(pp_leavetry)
     PL_curpm = newpm;  /* Don't pop $1 et al till now */
 
     LEAVE;
-    sv_setpv(ERRSV,"");
-    RETURNOP(retop);
+    sv_setpvn(ERRSV,"",0);
+    RETURN;
 }
 
-STATIC void
+STATIC OP *
 S_doparseform(pTHX_ SV *sv)
 {
     STRLEN len;
@@ -3487,16 +3672,26 @@ S_doparseform(pTHX_ SV *sv)
     bool noblank   = FALSE;
     bool repeat    = FALSE;
     bool postspace = FALSE;
-    U16 *fops;
-    register U16 *fpc;
-    U16 *linepc = 0;
+    U32 *fops;
+    register U32 *fpc;
+    U32 *linepc = 0;
     register I32 arg;
     bool ischop;
+    bool unchopnum = FALSE;
+    int maxops = 12; /* FF_LINEMARK + FF_END + 10 (\0 without preceding \n) */
 
     if (len == 0)
        Perl_croak(aTHX_ "Null picture in formline");
 
-    New(804, fops, (send - s)*3+10, U16);    /* Almost certainly too long... */
+    /* estimate the buffer size needed */
+    for (base = s; s <= send; s++) {
+       if (*s == '\n' || *s == '@' || *s == '^')
+           maxops += 10;
+    }
+    s = base;
+    base = Nullch;
+
+    Newx(fops, maxops, U32);
     fpc = fops;
 
     if (s < send) {
@@ -3523,8 +3718,12 @@ S_doparseform(pTHX_ SV *sv)
        case ' ': case '\t':
            skipspaces++;
            continue;
-       
-       case '\n': case 0:
+        case 0:
+           if (s < send) {
+               skipspaces = 0;
+                continue;
+            } /* else FALL THROUGH */
+       case '\n':
            arg = s - base;
            skipspaces++;
            arg -= skipspaces;
@@ -3580,8 +3779,12 @@ S_doparseform(pTHX_ SV *sv)
            *fpc++ = FF_FETCH;
            if (*s == '*') {
                s++;
-               *fpc++ = 0;
-               *fpc++ = FF_LINEGLOB;
+               *fpc++ = 2;  /* skip the @* or ^* */
+               if (ischop) {
+                   *fpc++ = FF_LINESNGL;
+                   *fpc++ = FF_CHOP;
+               } else
+                   *fpc++ = FF_LINEGLOB;
            }
            else if (*s == '#' || (*s == '.' && s[1] == '#')) {
                arg = ischop ? 512 : 0;
@@ -3589,9 +3792,7 @@ S_doparseform(pTHX_ SV *sv)
                while (*s == '#')
                    s++;
                if (*s == '.') {
-                   char *f;
-                   s++;
-                   f = s;
+                    const char * const f = ++s;
                    while (*s == '#')
                        s++;
                    arg |= 256 + (s - f);
@@ -3599,6 +3800,7 @@ S_doparseform(pTHX_ SV *sv)
                *fpc++ = s - base;              /* fieldsize for FETCH */
                *fpc++ = FF_DECIMAL;
                 *fpc++ = (U16)arg;
+                unchopnum |= ! ischop;
             }
             else if (*s == '0' && s[1] == '#') {  /* Zero padded decimals */
                 arg = ischop ? 512 : 0;
@@ -3607,9 +3809,7 @@ S_doparseform(pTHX_ SV *sv)
                 while (*s == '#')
                     s++;
                 if (*s == '.') {
-                    char *f;
-                    s++;
-                    f = s;
+                    const char * const f = ++s;
                     while (*s == '#')
                         s++;
                     arg |= 256 + (s - f);
@@ -3617,6 +3817,7 @@ S_doparseform(pTHX_ SV *sv)
                 *fpc++ = s - base;                /* fieldsize for FETCH */
                 *fpc++ = FF_0DECIMAL;
                *fpc++ = (U16)arg;
+                unchopnum |= ! ischop;
            }
            else {
                I32 prespace = 0;
@@ -3659,24 +3860,58 @@ S_doparseform(pTHX_ SV *sv)
     }
     *fpc++ = FF_END;
 
+    assert (fpc <= fops + maxops); /* ensure our buffer estimate was valid */
     arg = fpc - fops;
     { /* need to jump to the next word */
         int z;
        z = WORD_ALIGN - SvCUR(sv) % WORD_ALIGN;
-       SvGROW(sv, SvCUR(sv) + z + arg * sizeof(U16) + 4);
+       SvGROW(sv, SvCUR(sv) + z + arg * sizeof(U32) + 4);
        s = SvPVX(sv) + SvCUR(sv) + z;
     }
-    Copy(fops, s, arg, U16);
+    Copy(fops, s, arg, U32);
     Safefree(fops);
     sv_magic(sv, Nullsv, PERL_MAGIC_fm, Nullch, 0);
     SvCOMPILED_on(sv);
+
+    if (unchopnum && repeat)
+        DIE(aTHX_ "Repeated format line will never terminate (~~ and @#)");
+    return 0;
+}
+
+
+STATIC bool
+S_num_overflow(NV value, I32 fldsize, I32 frcsize)
+{
+    /* Can value be printed in fldsize chars, using %*.*f ? */
+    NV pwr = 1;
+    NV eps = 0.5;
+    bool res = FALSE;
+    int intsize = fldsize - (value < 0 ? 1 : 0);
+
+    if (frcsize & 256)
+        intsize--;
+    frcsize &= 255;
+    intsize -= frcsize;
+
+    while (intsize--) pwr *= 10.0;
+    while (frcsize--) eps /= 10.0;
+
+    if( value >= 0 ){
+        if (value + eps >= pwr)
+           res = TRUE;
+    } else {
+        if (value - eps <= -pwr)
+           res = TRUE;
+    }
+    return res;
 }
 
 static I32
 run_user_filter(pTHX_ int idx, SV *buf_sv, int maxlen)
 {
+    dVAR;
     SV *datasv = FILTER_DATA(idx);
-    int filter_has_file = IoLINES(datasv);
+    const int filter_has_file = IoLINES(datasv);
     GV *filter_child_proc = (GV *)IoFMT_GV(datasv);
     SV *filter_state = (SV *)IoTOP_GV(datasv);
     SV *filter_sub = (SV *)IoBOTTOM_GV(datasv);
@@ -3745,7 +3980,7 @@ run_user_filter(pTHX_ int idx, SV *buf_sv, int maxlen)
 /* perhaps someone can come up with a better name for
    this?  it is not really "absolute", per se ... */
 static bool
-S_path_is_absolute(pTHX_ char *name)
+S_path_is_absolute(pTHX_ const char *name)
 {
     if (PERL_FILE_IS_ABSOLUTE(name)
 #ifdef MACOS_TRADITIONAL
@@ -3760,3 +3995,13 @@ S_path_is_absolute(pTHX_ char *name)
     else
        return FALSE;
 }
+
+/*
+ * Local variables:
+ * c-indentation-style: bsd
+ * c-basic-offset: 4
+ * indent-tabs-mode: t
+ * End:
+ *
+ * ex: set ts=8 sts=4 sw=4 noet:
+ */