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[perl #131730] Fix exec PROGRAM LIST with empty LIST on VMS
[perl5.git] / regcomp.c
index 97cf29d..cc0ff96 100644 (file)
--- a/regcomp.c
+++ b/regcomp.c
@@ -462,7 +462,9 @@ typedef struct scan_data_t {
     SSize_t last_end;      /* min value, <0 unless valid. */
     SSize_t last_start_min;
     SSize_t last_start_max;
-    U8 longest;                    /* 0 = fixed is longest, 1 = float is longest */
+    U8      cur_is_floating; /* whether the last_* values should be set as
+                              * the next fixed (0) or floating (1)
+                              * substring */
 
     /* [0] is longest fixed substring so far, [1] is longest float so far */
     struct scan_data_substrs  substrs[2];
@@ -1029,6 +1031,7 @@ S_debug_studydata(pTHX_ const char *where, scan_data_t *data,
         );
 
         if (data->last_found) {
+            int i;
             Perl_re_printf(aTHX_
                 "Last:'%s' %" IVdf ":%" IVdf "/%" IVdf,
                     SvPVX_const(data->last_found),
@@ -1037,22 +1040,17 @@ S_debug_studydata(pTHX_ const char *where, scan_data_t *data,
                     (IV)data->last_start_max
             );
 
-            Perl_re_printf(aTHX_
-                " %sFixed:'%s' @ %" IVdf,
-                data->longest == 0 ? "*" : "",
-                SvPVX_const(data->substrs[0].str),
-                (IV)data->substrs[0].min_offset
-            );
-            S_debug_show_study_flags(aTHX_ data->substrs[0].flags," [","]");
-
-            Perl_re_printf(aTHX_
-                " %sFloat: '%s' @ %" IVdf "/%" IVdf,
-                data->longest == 1 ? "*" : "",
-                SvPVX_const(data->substrs[1].str),
-                (IV)data->substrs[1].min_offset,
-                (IV)data->substrs[1].max_offset
-            );
-            S_debug_show_study_flags(aTHX_ data->substrs[1].flags," [","]");
+            for (i = 0; i < 2; i++) {
+                Perl_re_printf(aTHX_
+                    " %s%s: '%s' @ %" IVdf "/%" IVdf,
+                    data->cur_is_floating == i ? "*" : "",
+                    i ? "Float" : "Fixed",
+                    SvPVX_const(data->substrs[i].str),
+                    (IV)data->substrs[i].min_offset,
+                    (IV)data->substrs[i].max_offset
+                );
+                S_debug_show_study_flags(aTHX_ data->substrs[i].flags," [","]");
+            }
         }
 
         Perl_re_printf( aTHX_ "\n");
@@ -1265,7 +1263,7 @@ S_cntrl_to_mnemonic(const U8 c)
 }
 
 /* Mark that we cannot extend a found fixed substring at this point.
-   Update the longest found anchored substring and the longest found
+   Update the longest found anchored substring or the longest found
    floating substrings if needed. */
 
 STATIC void
@@ -1273,26 +1271,20 @@ S_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data,
                     SSize_t *minlenp, int is_inf)
 {
     const STRLEN l = CHR_SVLEN(data->last_found);
-    SV * const longest_sv = data->substrs[data->longest].str;
+    SV * const longest_sv = data->substrs[data->cur_is_floating].str;
     const STRLEN old_l = CHR_SVLEN(longest_sv);
     GET_RE_DEBUG_FLAGS_DECL;
 
     PERL_ARGS_ASSERT_SCAN_COMMIT;
 
     if ((l >= old_l) && ((l > old_l) || (data->flags & SF_BEFORE_EOL))) {
+        const U8 i = data->cur_is_floating;
        SvSetMagicSV(longest_sv, data->last_found);
-       if (data->longest == 0) { /* fixed */
-           data->substrs[0].min_offset = l ? data->last_start_min : data->pos_min;
+        data->substrs[i].min_offset = l ? data->last_start_min : data->pos_min;
+
+       if (!i) /* fixed */
            data->substrs[0].max_offset = data->substrs[0].min_offset;
-           if (data->flags & SF_BEFORE_EOL)
-               data->substrs[0].flags |= (data->flags & SF_BEFORE_EOL);
-           else
-               data->substrs[0].flags &= ~SF_BEFORE_EOL;
-           data->substrs[0].minlenp = minlenp;
-           data->substrs[0].lookbehind = 0;
-       }
        else { /* float */
-           data->substrs[1].min_offset = l ? data->last_start_min : data->pos_min;
            data->substrs[1].max_offset = (l
                           ? data->last_start_max
                           : (data->pos_delta > SSize_t_MAX - data->pos_min
@@ -1301,15 +1293,16 @@ S_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data,
            if (is_inf
                 || (STRLEN)data->substrs[1].max_offset > (STRLEN)SSize_t_MAX)
                data->substrs[1].max_offset = SSize_t_MAX;
+        }
 
-           if (data->flags & SF_BEFORE_EOL)
-               data->substrs[1].flags |= (data->flags & SF_BEFORE_EOL);
-           else
-               data->substrs[1].flags &= ~SF_BEFORE_EOL;
-            data->substrs[1].minlenp = minlenp;
-            data->substrs[1].lookbehind = 0;
-       }
+        if (data->flags & SF_BEFORE_EOL)
+            data->substrs[i].flags |= (data->flags & SF_BEFORE_EOL);
+        else
+            data->substrs[i].flags &= ~SF_BEFORE_EOL;
+        data->substrs[i].minlenp = minlenp;
+        data->substrs[i].lookbehind = 0;
     }
+
     SvCUR_set(data->last_found, 0);
     {
        SV * const sv = data->last_found;
@@ -4398,7 +4391,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                    else
                        data->pos_delta += max1 - min1;
                    if (max1 != min1 || is_inf)
-                       data->longest = 1 /*float*/;
+                       data->cur_is_floating = 1;
                }
                min += min1;
                if (delta == SSize_t_MAX
@@ -4845,7 +4838,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                      * */
                     if (flags & SCF_DO_SUBSTR) {
                         scan_commit(pRExC_state, data, minlenp, is_inf);
-                        data->longest = 1; /* float */
+                        data->cur_is_floating = 1;
                     }
                     is_inf = is_inf_internal = 1;
                     if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
@@ -4973,7 +4966,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                 }
                 data->pos_delta += min_subtract;
                if (min_subtract) {
-                   data->longest = 1; /* float */
+                   data->cur_is_floating = 1; /* float */
                }
            }
 
@@ -5040,7 +5033,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                if (flags & SCF_DO_SUBSTR) {
                     scan_commit(pRExC_state, data, minlenp, is_inf);
                     /* Cannot extend fixed substrings */
-                   data->longest = 1; /* float */
+                   data->cur_is_floating = 1; /* float */
                }
                 is_inf = is_inf_internal = 1;
                 scan = regnext(scan);
@@ -5130,7 +5123,7 @@ S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
                }
                if (!scan)              /* It was not CURLYX, but CURLY. */
                    scan = next;
-               if (!(flags & SCF_TRIE_DOING_RESTUDY)
+               if (((flags & (SCF_TRIE_DOING_RESTUDY|SCF_DO_SUBSTR))==SCF_DO_SUBSTR)
                    /* ? quantifier ok, except for (?{ ... }) */
                    && (next_is_eval || !(mincount == 0 && maxcount == 1))
                    && (minnext == 0) && (deltanext == 0)
@@ -5378,7 +5371,7 @@ Perl_re_printf( aTHX_  "LHS=%" UVuf " RHS=%" UVuf "\n",
                                ? SSize_t_MAX
                                : data->pos_min + data->pos_delta - last_chrs;
                        }
-                       data->longest = 1; /* float */
+                       data->cur_is_floating = 1; /* float */
                    }
                    SvREFCNT_dec(last_str);
                }
@@ -5402,7 +5395,7 @@ Perl_re_printf( aTHX_  "LHS=%" UVuf " RHS=%" UVuf "\n",
                if (flags & SCF_DO_SUBSTR) {
                     /* Cannot expect anything... */
                     scan_commit(pRExC_state, data, minlenp, is_inf);
-                   data->longest = 1; /* float */
+                   data->cur_is_floating = 1; /* float */
                }
                is_inf = is_inf_internal = 1;
                if (flags & SCF_DO_STCLASS_OR) {
@@ -5449,7 +5442,7 @@ Perl_re_printf( aTHX_  "LHS=%" UVuf " RHS=%" UVuf "\n",
                 scan_commit(pRExC_state, data, minlenp, is_inf);
                data->pos_min += 1;
                data->pos_delta += 1;
-               data->longest = 1; /* float */
+               data->cur_is_floating = 1; /* float */
            }
        }
        else if (REGNODE_SIMPLE(OP(scan))) {
@@ -5765,29 +5758,29 @@ Perl_re_printf( aTHX_  "LHS=%" UVuf " RHS=%" UVuf "\n",
                         data->flags |= SF_HAS_EVAL;
                     data->whilem_c = data_fake.whilem_c;
                     if ((flags & SCF_DO_SUBSTR) && data_fake.last_found) {
+                        int i;
                         if (RExC_rx->minlen<*minnextp)
                             RExC_rx->minlen=*minnextp;
                         scan_commit(pRExC_state, &data_fake, minnextp, is_inf);
                         SvREFCNT_dec_NN(data_fake.last_found);
 
-                        if (data_fake.substrs[0].minlenp != minlenp) {
-                            data->substrs[0].min_offset = data_fake.substrs[0].min_offset;
-                            data->substrs[0].max_offset = data_fake.substrs[0].max_offset;
-                            data->substrs[0].minlenp = data_fake.substrs[0].minlenp;
-                            data->substrs[0].lookbehind += scan->flags;
-                        }
-
-                        if (data_fake.substrs[1].minlenp != minlenp) {
-                            data->substrs[1].minlenp = data_fake.substrs[1].minlenp;
-                            data->substrs[1].min_offset = data_fake.substrs[1].min_offset;
-                            data->substrs[1].max_offset = data_fake.substrs[1].max_offset;
-                            data->substrs[1].lookbehind += scan->flags;
+                        for (i = 0; i < 2; i++) {
+                            if (data_fake.substrs[i].minlenp != minlenp) {
+                                data->substrs[i].min_offset =
+                                            data_fake.substrs[i].min_offset;
+                                data->substrs[i].max_offset =
+                                            data_fake.substrs[i].max_offset;
+                                data->substrs[i].minlenp =
+                                            data_fake.substrs[i].minlenp;
+                                data->substrs[i].lookbehind += scan->flags;
+                            }
                         }
                     }
                 }
            }
 #endif
        }
+
        else if (OP(scan) == OPEN) {
            if (stopparen != (I32)ARG(scan))
                pars++;
@@ -5824,7 +5817,7 @@ Perl_re_printf( aTHX_  "LHS=%" UVuf " RHS=%" UVuf "\n",
        {
                if (flags & SCF_DO_SUBSTR) {
                     scan_commit(pRExC_state, data, minlenp, is_inf);
-                   data->longest = 1; /* float */
+                   data->cur_is_floating = 1; /* float */
                }
                is_inf = is_inf_internal = 1;
                if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
@@ -5935,7 +5928,7 @@ Perl_re_printf( aTHX_  "LHS=%" UVuf " RHS=%" UVuf "\n",
                 data->pos_min += min1;
                 data->pos_delta += max1 - min1;
                 if (max1 != min1 || is_inf)
-                    data->longest = 1; /* float */
+                    data->cur_is_floating = 1; /* float */
             }
             min += min1;
             if (delta != SSize_t_MAX)
@@ -5979,7 +5972,7 @@ Perl_re_printf( aTHX_  "LHS=%" UVuf " RHS=%" UVuf "\n",
                data->pos_min += trie->minlen;
                data->pos_delta += (trie->maxlen - trie->minlen);
                if (trie->maxlen != trie->minlen)
-                   data->longest = 1; /* float */
+                   data->cur_is_floating = 1; /* float */
            }
            if (trie->jump) /* no more substrings -- for now /grr*/
                flags &= ~SCF_DO_SUBSTR;
@@ -6752,7 +6745,7 @@ S_compile_runtime_code(pTHX_ RExC_state_t * const pRExC_state,
 
 STATIC bool
 S_setup_longest(pTHX_ RExC_state_t *pRExC_state,
-                      SV** rx_utf8, SV** rx_substr, SSize_t* rx_end_shift,
+                      struct reg_substr_datum  *rsd,
                       struct scan_data_substrs *sub,
                       STRLEN longest_length)
 {
@@ -6778,18 +6771,18 @@ S_setup_longest(pTHX_ RExC_state_t *pRExC_state,
     /* copy the information about the longest from the reg_scan_data
         over to the program. */
     if (SvUTF8(sub->str)) {
-        *rx_utf8 = sub->str;
-        *rx_substr = NULL;
+        rsd->substr      = NULL;
+        rsd->utf8_substr = sub->str;
     } else {
-        *rx_substr = sub->str;
-        *rx_utf8 = NULL;
+        rsd->substr      = sub->str;
+        rsd->utf8_substr = NULL;
     }
     /* end_shift is how many chars that must be matched that
         follow this item. We calculate it ahead of time as once the
         lookbehind offset is added in we lose the ability to correctly
         calculate it.*/
     ml = sub->minlenp ? *(sub->minlenp) : (SSize_t)longest_length;
-    *rx_end_shift = ml - sub->min_offset
+    rsd->end_shift = ml - sub->min_offset
         - longest_length
             /* XXX SvTAIL is always false here - did you mean FBMcf_TAIL
              * intead? - DAPM
@@ -7269,8 +7262,8 @@ Perl_re_op_compile(pTHX_ SV ** const patternp, int pat_count,
         /* make sure PL_bitcount bounds not exceeded */
         assert(sizeof(STD_PAT_MODS) <= 8);
 
-        Newx(p, wraplen + 1, char); /* +1 for the ending NUL */
-       r->xpv_len_u.xpvlenu_pv = p;
+        p = sv_grow(MUTABLE_SV(rx), wraplen + 1); /* +1 for the ending NUL */
+        SvPOK_on(rx);
        if (RExC_utf8)
            SvFLAGS(rx) |= SVf_UTF8;
         *p++='('; *p++='?';
@@ -7430,12 +7423,14 @@ Perl_re_op_compile(pTHX_ SV ** const patternp, int pat_count,
     if (!(RExC_seen & REG_TOP_LEVEL_BRANCHES_SEEN)) { /*  Only one top-level choice.
                                                   */
        SSize_t fake;
-       STRLEN longest_float_length, longest_fixed_length;
+       STRLEN longest_length[2];
        regnode_ssc ch_class; /* pointed to by data */
        int stclass_flag;
        SSize_t last_close = 0; /* pointed to by data */
         regnode *first= scan;
         regnode *first_next= regnext(first);
+        int i;
+
        /*
         * Skip introductions and multiplicators >= 1
         * so that we can extract the 'meat' of the pattern that must
@@ -7561,7 +7556,7 @@ Perl_re_op_compile(pTHX_ SV ** const patternp, int pat_count,
        data.substrs[0].str = newSVpvs("");
        data.substrs[1].str = newSVpvs("");
        data.last_found = newSVpvs("");
-       data.longest = 0; /* fixed */
+       data.cur_is_floating = 0; /* initially any found substring is fixed */
        ENTER_with_name("study_chunk");
        SAVEFREESV(data.substrs[0].str);
        SAVEFREESV(data.substrs[1].str);
@@ -7587,7 +7582,7 @@ Perl_re_op_compile(pTHX_ SV ** const patternp, int pat_count,
         CHECK_RESTUDY_GOTO_butfirst(LEAVE_with_name("study_chunk"));
 
 
-       if ( RExC_npar == 1 && data.longest == 0 /*fixed */
+       if ( RExC_npar == 1 && !data.cur_is_floating
             && data.last_start_min == 0 && data.last_end > 0
             && !RExC_seen_zerolen
              && !(RExC_seen & REG_VERBARG_SEEN)
@@ -7597,63 +7592,49 @@ Perl_re_op_compile(pTHX_ SV ** const patternp, int pat_count,
         }
        scan_commit(pRExC_state, &data,&minlen,0);
 
-       longest_float_length = CHR_SVLEN(data.substrs[1].str);
-
-        if (! ((SvCUR(data.substrs[0].str)  /* ok to leave SvCUR */
-                   && data.substrs[0].min_offset == data.substrs[1].min_offset
-                   && SvCUR(data.substrs[0].str) == SvCUR(data.substrs[1].str)))
-            && S_setup_longest (aTHX_ pRExC_state,
-                                    &(r->float_utf8),
-                                    &(r->float_substr),
-                                    &(r->float_end_shift),
-                                    &(data.substrs[1]),
-                                    longest_float_length))
-        {
-           r->substrs->data[1].min_offset =
-                    data.substrs[1].min_offset - data.substrs[1].lookbehind;
-
-           r->substrs->data[1].max_offset = data.substrs[1].max_offset;
-           if (data.substrs[1].max_offset < SSize_t_MAX) /* Don't offset infinity */
-               r->substrs->data[1].max_offset -= data.substrs[1].lookbehind;
-
-           SvREFCNT_inc_simple_void_NN(data.substrs[1].str);
-       }
-       else {
-           r->float_substr = r->float_utf8 = NULL;
-           longest_float_length = 0;
-       }
 
-       longest_fixed_length = CHR_SVLEN(data.substrs[0].str);
-
-        if (S_setup_longest (aTHX_ pRExC_state,
-                                &(r->anchored_utf8),
-                                &(r->anchored_substr),
-                                &(r->anchored_end_shift),
-                                &(data.substrs[0]),
-                                longest_fixed_length))
-        {
-           r->substrs->data[0].min_offset =
-                    data.substrs[0].min_offset - data.substrs[0].lookbehind;
-            /* XXX this calc isn't necessary for anchored, but is done
-             * for consistency with float code path */
-           r->substrs->data[0].max_offset = data.substrs[0].max_offset;
+        /* XXX this is done in reverse order because that's the way the
+         * code was before it was parameterised. Don't know whether it
+         * actually needs doing in reverse order. DAPM */
+        for (i = 1; i >= 0; i--) {
+            longest_length[i] = CHR_SVLEN(data.substrs[i].str);
 
-           if (data.substrs[0].max_offset < SSize_t_MAX) /* Don't offset infinity */
-               r->substrs->data[0].max_offset -= data.substrs[0].lookbehind;
+            if (   !(   i
+                     && SvCUR(data.substrs[0].str)  /* ok to leave SvCUR */
+                     &&    data.substrs[0].min_offset
+                        == data.substrs[1].min_offset
+                     &&    SvCUR(data.substrs[0].str)
+                        == SvCUR(data.substrs[1].str)
+                    )
+                && S_setup_longest (aTHX_ pRExC_state,
+                                        &(r->substrs->data[i]),
+                                        &(data.substrs[i]),
+                                        longest_length[i]))
+            {
+                r->substrs->data[i].min_offset =
+                        data.substrs[i].min_offset - data.substrs[i].lookbehind;
+
+                r->substrs->data[i].max_offset = data.substrs[i].max_offset;
+                /* Don't offset infinity */
+                if (data.substrs[i].max_offset < SSize_t_MAX)
+                    r->substrs->data[i].max_offset -= data.substrs[i].lookbehind;
+                SvREFCNT_inc_simple_void_NN(data.substrs[i].str);
+            }
+            else {
+                r->substrs->data[i].substr      = NULL;
+                r->substrs->data[i].utf8_substr = NULL;
+                longest_length[i] = 0;
+            }
+        }
 
-           SvREFCNT_inc_simple_void_NN(data.substrs[0].str);
-       }
-       else {
-           r->anchored_substr = r->anchored_utf8 = NULL;
-           longest_fixed_length = 0;
-       }
        LEAVE_with_name("study_chunk");
 
        if (ri->regstclass
            && (OP(ri->regstclass) == REG_ANY || OP(ri->regstclass) == SANY))
            ri->regstclass = NULL;
 
-       if ((!(r->anchored_substr || r->anchored_utf8) || r->anchored_offset)
+       if ((!(r->substrs->data[0].substr || r->substrs->data[0].utf8_substr)
+              || r->substrs->data[0].min_offset)
            && stclass_flag
             && ! (ANYOF_FLAGS(data.start_class) & SSC_MATCHES_EMPTY_STRING)
            && is_ssc_worth_it(pRExC_state, data.start_class))
@@ -7676,26 +7657,17 @@ Perl_re_op_compile(pTHX_ SV ** const patternp, int pat_count,
             data.start_class = NULL;
        }
 
-        /* A temporary algorithm prefers floated substr to fixed one to dig
-         * more info. */
-       if (longest_fixed_length > longest_float_length) {
-           r->substrs->check_ix = 0;
-           r->check_end_shift = r->anchored_end_shift;
-           r->check_substr = r->anchored_substr;
-           r->check_utf8 = r->anchored_utf8;
-           r->check_offset_min = r->substrs->data[0].min_offset;
-           r->check_offset_max = r->substrs->data[0].max_offset;
-            if (r->intflags & (PREGf_ANCH_SBOL|PREGf_ANCH_GPOS))
-                r->intflags |= PREGf_NOSCAN;
-       }
-       else {
-           r->substrs->check_ix = 1;
-           r->check_end_shift = r->float_end_shift;
-           r->check_substr = r->float_substr;
-           r->check_utf8 = r->float_utf8;
-           r->check_offset_min = r->substrs->data[1].min_offset;
-           r->check_offset_max = r->substrs->data[1].max_offset;
-       }
+        /* A temporary algorithm prefers floated substr to fixed one of
+         * same length to dig more info. */
+       i = (longest_length[0] <= longest_length[1]);
+        r->substrs->check_ix = i;
+        r->check_end_shift  = r->substrs->data[i].end_shift;
+        r->check_substr     = r->substrs->data[i].substr;
+        r->check_utf8       = r->substrs->data[i].utf8_substr;
+        r->check_offset_min = r->substrs->data[i].min_offset;
+        r->check_offset_max = r->substrs->data[i].max_offset;
+        if (!i && (r->intflags & (PREGf_ANCH_SBOL|PREGf_ANCH_GPOS)))
+            r->intflags |= PREGf_NOSCAN;
 
        if ((r->check_substr || r->check_utf8) ) {
            r->extflags |= RXf_USE_INTUIT;
@@ -7704,10 +7676,10 @@ Perl_re_op_compile(pTHX_ SV ** const patternp, int pat_count,
        }
 
        /* XXX Unneeded? dmq (shouldn't as this is handled elsewhere)
-       if ( (STRLEN)minlen < longest_float_length )
-            minlen= longest_float_length;
-        if ( (STRLEN)minlen < longest_fixed_length )
-            minlen= longest_fixed_length;
+       if ( (STRLEN)minlen < longest_length[1] )
+            minlen= longest_length[1];
+        if ( (STRLEN)minlen < longest_length[0] )
+            minlen= longest_length[0];
         */
     }
     else {
@@ -7733,8 +7705,12 @@ Perl_re_op_compile(pTHX_ SV ** const patternp, int pat_count,
 
         CHECK_RESTUDY_GOTO_butfirst(NOOP);
 
-       r->check_substr = r->check_utf8 = r->anchored_substr = r->anchored_utf8
-               = r->float_substr = r->float_utf8 = NULL;
+       r->check_substr = NULL;
+        r->check_utf8 = NULL;
+        r->substrs->data[0].substr      = NULL;
+        r->substrs->data[0].utf8_substr = NULL;
+        r->substrs->data[1].substr      = NULL;
+        r->substrs->data[1].utf8_substr = NULL;
 
         if (! (ANYOF_FLAGS(data.start_class) & SSC_MATCHES_EMPTY_STRING)
            && is_ssc_worth_it(pRExC_state, data.start_class))
@@ -11806,14 +11782,12 @@ S_regpiece(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, U32 depth)
            if ((flags&SIMPLE)) {
                 if (min == 0 && max == REG_INFTY) {
                     reginsert(pRExC_state, STAR, ret, depth+1);
-                    ret->flags = 0;
                     MARK_NAUGHTY(4);
                     RExC_seen |= REG_UNBOUNDED_QUANTIFIER_SEEN;
                     goto nest_check;
                 }
                 if (min == 1 && max == REG_INFTY) {
                     reginsert(pRExC_state, PLUS, ret, depth+1);
-                    ret->flags = 0;
                     MARK_NAUGHTY(3);
                     RExC_seen |= REG_UNBOUNDED_QUANTIFIER_SEEN;
                     goto nest_check;
@@ -11926,7 +11900,6 @@ S_regpiece(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, U32 depth)
         ender = reg_node(pRExC_state, SUCCEED);
         REGTAIL(pRExC_state, ret, ender);
         reginsert(pRExC_state, SUSPEND, ret, depth+1);
-        ret->flags = 0;
         ender = reg_node(pRExC_state, TAIL);
         REGTAIL(pRExC_state, ret, ender);
     }
@@ -12223,14 +12196,16 @@ S_grok_bslash_N(pTHX_ RExC_state_t *pRExC_state,
        }
         sv_catpv(substitute_parse, ")");
 
-        RExC_parse = RExC_start = RExC_adjusted_start = SvPV(substitute_parse,
-                                                             len);
+        len = SvCUR(substitute_parse);
 
        /* Don't allow empty number */
        if (len < (STRLEN) 8) {
             RExC_parse = endbrace;
            vFAIL("Invalid hexadecimal number in \\N{U+...}");
        }
+
+        RExC_parse = RExC_start = RExC_adjusted_start
+                                              = SvPV_nolen(substitute_parse);
        RExC_end = RExC_parse + len;
 
         /* The values are Unicode, and therefore not subject to recoding, but
@@ -13345,6 +13320,7 @@ S_regatom(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, U32 depth)
                             goto loopdone;
                         }
                         p = RExC_parse;
+                        RExC_parse = parse_start;
                         if (ender > 0xff) {
                             REQUIRE_UTF8(flagp);
                         }
@@ -18661,6 +18637,7 @@ S_reg2Lanode(pTHX_ RExC_state_t *pRExC_state, const U8 op, const U32 arg1, const
 * if (PASS2)
 *     NEXT_OFF(orig_emit) = regarglen[OPFAIL] + NODE_STEP_REGNODE;
 *
+* ALSO NOTE - operand->flags will be set to 0 as well.
 */
 STATIC void
 S_reginsert(pTHX_ RExC_state_t *pRExC_state, U8 op, regnode *operand, U32 depth)
@@ -18734,7 +18711,6 @@ S_reginsert(pTHX_ RExC_state_t *pRExC_state, U8 op, regnode *operand, U32 depth)
 #endif
     }
 
-
     place = operand;           /* Op node, where operand used to be. */
 #ifdef RE_TRACK_PATTERN_OFFSETS
     if (RExC_offsets) {         /* MJD */
@@ -18753,6 +18729,7 @@ S_reginsert(pTHX_ RExC_state_t *pRExC_state, U8 op, regnode *operand, U32 depth)
     }
 #endif
     src = NEXTOPER(place);
+    place->flags = 0;
     FILL_ADVANCE_NODE(place, op);
     Zero(src, offset, regnode);
 }
@@ -18987,6 +18964,7 @@ void
 Perl_regdump(pTHX_ const regexp *r)
 {
 #ifdef DEBUGGING
+    int i;
     SV * const sv = sv_newmortal();
     SV *dsv= sv_newmortal();
     RXi_GET_DECL(r,ri);
@@ -18997,41 +18975,40 @@ Perl_regdump(pTHX_ const regexp *r)
     (void)dumpuntil(r, ri->program, ri->program + 1, NULL, NULL, sv, 0, 0);
 
     /* Header fields of interest. */
-    if (r->anchored_substr) {
-       RE_PV_QUOTED_DECL(s, 0, dsv, SvPVX_const(r->anchored_substr),
-           RE_SV_DUMPLEN(r->anchored_substr), 30);
-        Perl_re_printf( aTHX_
-                     "anchored %s%s at %" IVdf " ",
-                     s, RE_SV_TAIL(r->anchored_substr),
-                     (IV)r->anchored_offset);
-    } else if (r->anchored_utf8) {
-       RE_PV_QUOTED_DECL(s, 1, dsv, SvPVX_const(r->anchored_utf8),
-           RE_SV_DUMPLEN(r->anchored_utf8), 30);
-        Perl_re_printf( aTHX_
-                     "anchored utf8 %s%s at %" IVdf " ",
-                     s, RE_SV_TAIL(r->anchored_utf8),
-                     (IV)r->anchored_offset);
-    }
-    if (r->float_substr) {
-       RE_PV_QUOTED_DECL(s, 0, dsv, SvPVX_const(r->float_substr),
-           RE_SV_DUMPLEN(r->float_substr), 30);
-        Perl_re_printf( aTHX_
-                     "floating %s%s at %" IVdf "..%" UVuf " ",
-                     s, RE_SV_TAIL(r->float_substr),
-                     (IV)r->float_min_offset, (UV)r->float_max_offset);
-    } else if (r->float_utf8) {
-       RE_PV_QUOTED_DECL(s, 1, dsv, SvPVX_const(r->float_utf8),
-           RE_SV_DUMPLEN(r->float_utf8), 30);
-        Perl_re_printf( aTHX_
-                     "floating utf8 %s%s at %" IVdf "..%" UVuf " ",
-                     s, RE_SV_TAIL(r->float_utf8),
-                     (IV)r->float_min_offset, (UV)r->float_max_offset);
+    for (i = 0; i < 2; i++) {
+        if (r->substrs->data[i].substr) {
+            RE_PV_QUOTED_DECL(s, 0, dsv,
+                            SvPVX_const(r->substrs->data[i].substr),
+                            RE_SV_DUMPLEN(r->substrs->data[i].substr),
+                            30);
+            Perl_re_printf( aTHX_
+                          "%s %s%s at %" IVdf "..%" UVuf " ",
+                          i ? "floating" : "anchored",
+                          s,
+                          RE_SV_TAIL(r->substrs->data[i].substr),
+                          (IV)r->substrs->data[i].min_offset,
+                          (UV)r->substrs->data[i].max_offset);
+        }
+        else if (r->substrs->data[i].utf8_substr) {
+            RE_PV_QUOTED_DECL(s, 1, dsv,
+                            SvPVX_const(r->substrs->data[i].utf8_substr),
+                            RE_SV_DUMPLEN(r->substrs->data[i].utf8_substr),
+                            30);
+            Perl_re_printf( aTHX_
+                          "%s utf8 %s%s at %" IVdf "..%" UVuf " ",
+                          i ? "floating" : "anchored",
+                          s,
+                          RE_SV_TAIL(r->substrs->data[i].utf8_substr),
+                          (IV)r->substrs->data[i].min_offset,
+                          (UV)r->substrs->data[i].max_offset);
+        }
     }
+
     if (r->check_substr || r->check_utf8)
         Perl_re_printf( aTHX_
                      (const char *)
-                     (r->check_substr == r->float_substr
-                      && r->check_utf8 == r->float_utf8
+                     (   r->check_substr == r->substrs->data[1].substr
+                      && r->check_utf8   == r->substrs->data[1].utf8_substr
                       ? "(checking floating" : "(checking anchored"));
     if (r->intflags & PREGf_NOSCAN)
         Perl_re_printf( aTHX_  " noscan");
@@ -19464,8 +19441,11 @@ Perl_regprop(pTHX_ const regexp *prog, SV *sv, const regnode *o, const regmatch_
 
     /* add on the verb argument if there is one */
     if ( ( k == VERB || OP(o) == ACCEPT || OP(o) == OPFAIL ) && o->flags) {
-        Perl_sv_catpvf(aTHX_ sv, ":%" SVf,
+        if ( ARG(o) )
+            Perl_sv_catpvf(aTHX_ sv, ":%" SVf,
                        SVfARG((MUTABLE_SV(progi->data->data[ ARG( o ) ]))));
+        else
+            sv_catpvs(sv, ":NULL");
     }
 #else
     PERL_UNUSED_CONTEXT;
@@ -19540,13 +19520,13 @@ Perl_pregfree2(pTHX_ REGEXP *rx)
     } else {
         CALLREGFREE_PVT(rx); /* free the private data */
         SvREFCNT_dec(RXp_PAREN_NAMES(r));
-       Safefree(r->xpv_len_u.xpvlenu_pv);
     }
     if (r->substrs) {
-        SvREFCNT_dec(r->anchored_substr);
-        SvREFCNT_dec(r->anchored_utf8);
-        SvREFCNT_dec(r->float_substr);
-        SvREFCNT_dec(r->float_utf8);
+        int i;
+        for (i = 0; i < 2; i++) {
+            SvREFCNT_dec(r->substrs->data[i].substr);
+            SvREFCNT_dec(r->substrs->data[i].utf8_substr);
+        }
        Safefree(r->substrs);
     }
     RX_MATCH_COPY_FREE(rx);
@@ -19557,12 +19537,19 @@ Perl_pregfree2(pTHX_ REGEXP *rx)
     SvREFCNT_dec(r->qr_anoncv);
     if (r->recurse_locinput)
         Safefree(r->recurse_locinput);
-    rx->sv_u.svu_rx = 0;
 }
 
+
 /*  reg_temp_copy()
 
-    This is a hacky workaround to the structural issue of match results
+    Copy ssv to dsv, both of which should of type SVt_REGEXP or SVt_PVLV,
+    except that dsv will be created if NULL.
+
+    This function is used in two main ways. First to implement
+        $r = qr/....; $s = $$r;
+
+    Secondly, it is used as a hacky workaround to the structural issue of
+    match results
     being stored in the regexp structure which is in turn stored in
     PL_curpm/PL_reg_curpm. The problem is that due to qr// the pattern
     could be PL_curpm in multiple contexts, and could require multiple
@@ -19578,75 +19565,80 @@ Perl_pregfree2(pTHX_ REGEXP *rx)
 
 
 REGEXP *
-Perl_reg_temp_copy (pTHX_ REGEXP *ret_x, REGEXP *rx)
+Perl_reg_temp_copy(pTHX_ REGEXP *dsv, REGEXP *ssv)
 {
-    struct regexp *ret;
-    struct regexp *const r = ReANY(rx);
-    const bool islv = ret_x && SvTYPE(ret_x) == SVt_PVLV;
+    struct regexp *drx;
+    struct regexp *const srx = ReANY(ssv);
+    const bool islv = dsv && SvTYPE(dsv) == SVt_PVLV;
 
     PERL_ARGS_ASSERT_REG_TEMP_COPY;
 
-    if (!ret_x)
-       ret_x = (REGEXP*) newSV_type(SVt_REGEXP);
+    if (!dsv)
+       dsv = (REGEXP*) newSV_type(SVt_REGEXP);
     else {
-       SvOK_off((SV *)ret_x);
+       SvOK_off((SV *)dsv);
        if (islv) {
-           /* For PVLVs, SvANY points to the xpvlv body while sv_u points
-              to the regexp.  (For SVt_REGEXPs, sv_upgrade has already
-              made both spots point to the same regexp body.) */
+           /* For PVLVs, the head (sv_any) points to an XPVLV, while
+             * the LV's xpvlenu_rx will point to a regexp body, which
+             * we allocate here */
            REGEXP *temp = (REGEXP *)newSV_type(SVt_REGEXP);
-           assert(!SvPVX(ret_x));
-           ret_x->sv_u.svu_rx = temp->sv_any;
+           assert(!SvPVX(dsv));
+            ((XPV*)SvANY(dsv))->xpv_len_u.xpvlenu_rx = temp->sv_any;
            temp->sv_any = NULL;
            SvFLAGS(temp) = (SvFLAGS(temp) & ~SVTYPEMASK) | SVt_NULL;
            SvREFCNT_dec_NN(temp);
            /* SvCUR still resides in the xpvlv struct, so the regexp copy-
               ing below will not set it. */
-           SvCUR_set(ret_x, SvCUR(rx));
+           SvCUR_set(dsv, SvCUR(ssv));
        }
     }
     /* This ensures that SvTHINKFIRST(sv) is true, and hence that
        sv_force_normal(sv) is called.  */
-    SvFAKE_on(ret_x);
-    ret = ReANY(ret_x);
+    SvFAKE_on(dsv);
+    drx = ReANY(dsv);
 
-    SvFLAGS(ret_x) |= SvUTF8(rx);
+    SvFLAGS(dsv) |= SvFLAGS(ssv) & (SVf_POK|SVp_POK|SVf_UTF8);
+    SvPV_set(dsv, RX_WRAPPED(ssv));
     /* We share the same string buffer as the original regexp, on which we
        hold a reference count, incremented when mother_re is set below.
        The string pointer is copied here, being part of the regexp struct.
      */
-    memcpy(&(ret->xpv_cur), &(r->xpv_cur),
+    memcpy(&(drx->xpv_cur), &(srx->xpv_cur),
           sizeof(regexp) - STRUCT_OFFSET(regexp, xpv_cur));
-    if (r->offs) {
-        const I32 npar = r->nparens+1;
-        Newx(ret->offs, npar, regexp_paren_pair);
-        Copy(r->offs, ret->offs, npar, regexp_paren_pair);
-    }
-    if (r->substrs) {
-        Newx(ret->substrs, 1, struct reg_substr_data);
-       StructCopy(r->substrs, ret->substrs, struct reg_substr_data);
+    if (!islv)
+        SvLEN_set(dsv, 0);
+    if (srx->offs) {
+        const I32 npar = srx->nparens+1;
+        Newx(drx->offs, npar, regexp_paren_pair);
+        Copy(srx->offs, drx->offs, npar, regexp_paren_pair);
+    }
+    if (srx->substrs) {
+        int i;
+        Newx(drx->substrs, 1, struct reg_substr_data);
+       StructCopy(srx->substrs, drx->substrs, struct reg_substr_data);
 
-       SvREFCNT_inc_void(ret->anchored_substr);
-       SvREFCNT_inc_void(ret->anchored_utf8);
-       SvREFCNT_inc_void(ret->float_substr);
-       SvREFCNT_inc_void(ret->float_utf8);
+        for (i = 0; i < 2; i++) {
+            SvREFCNT_inc_void(drx->substrs->data[i].substr);
+            SvREFCNT_inc_void(drx->substrs->data[i].utf8_substr);
+        }
 
        /* check_substr and check_utf8, if non-NULL, point to either their
           anchored or float namesakes, and don't hold a second reference.  */
     }
-    RX_MATCH_COPIED_off(ret_x);
+    RX_MATCH_COPIED_off(dsv);
 #ifdef PERL_ANY_COW
-    ret->saved_copy = NULL;
+    drx->saved_copy = NULL;
 #endif
-    ret->mother_re = ReREFCNT_inc(r->mother_re ? r->mother_re : rx);
-    SvREFCNT_inc_void(ret->qr_anoncv);
-    if (r->recurse_locinput)
-        Newxz(ret->recurse_locinput,r->nparens + 1,char *);
+    drx->mother_re = ReREFCNT_inc(srx->mother_re ? srx->mother_re : ssv);
+    SvREFCNT_inc_void(drx->qr_anoncv);
+    if (srx->recurse_locinput)
+        Newxz(drx->recurse_locinput,srx->nparens + 1,char *);
 
-    return ret_x;
+    return dsv;
 }
 #endif
 
+
 /* regfree_internal()
 
    Free the private data in a regexp. This is overloadable by
@@ -19808,36 +19800,41 @@ Perl_re_dup_guts(pTHX_ const REGEXP *sstr, REGEXP *dstr, CLONE_PARAMS *param)
        /* Do it this way to avoid reading from *r after the StructCopy().
           That way, if any of the sv_dup_inc()s dislodge *r from the L1
           cache, it doesn't matter.  */
+        int i;
        const bool anchored = r->check_substr
-           ? r->check_substr == r->anchored_substr
-           : r->check_utf8 == r->anchored_utf8;
+           ? r->check_substr == r->substrs->data[0].substr
+           : r->check_utf8   == r->substrs->data[0].utf8_substr;
         Newx(ret->substrs, 1, struct reg_substr_data);
        StructCopy(r->substrs, ret->substrs, struct reg_substr_data);
 
-       ret->anchored_substr = sv_dup_inc(ret->anchored_substr, param);
-       ret->anchored_utf8 = sv_dup_inc(ret->anchored_utf8, param);
-       ret->float_substr = sv_dup_inc(ret->float_substr, param);
-       ret->float_utf8 = sv_dup_inc(ret->float_utf8, param);
+        for (i = 0; i < 2; i++) {
+            ret->substrs->data[i].substr =
+                        sv_dup_inc(ret->substrs->data[i].substr, param);
+            ret->substrs->data[i].utf8_substr =
+                        sv_dup_inc(ret->substrs->data[i].utf8_substr, param);
+        }
 
        /* check_substr and check_utf8, if non-NULL, point to either their
           anchored or float namesakes, and don't hold a second reference.  */
 
        if (ret->check_substr) {
            if (anchored) {
-               assert(r->check_utf8 == r->anchored_utf8);
-               ret->check_substr = ret->anchored_substr;
-               ret->check_utf8 = ret->anchored_utf8;
+               assert(r->check_utf8 == r->substrs->data[0].utf8_substr);
+
+               ret->check_substr = ret->substrs->data[0].substr;
+               ret->check_utf8   = ret->substrs->data[0].utf8_substr;
            } else {
-               assert(r->check_substr == r->float_substr);
-               assert(r->check_utf8 == r->float_utf8);
-               ret->check_substr = ret->float_substr;
-               ret->check_utf8 = ret->float_utf8;
+               assert(r->check_substr == r->substrs->data[1].substr);
+               assert(r->check_utf8   == r->substrs->data[1].utf8_substr);
+
+               ret->check_substr = ret->substrs->data[1].substr;
+               ret->check_utf8   = ret->substrs->data[1].utf8_substr;
            }
        } else if (ret->check_utf8) {
            if (anchored) {
-               ret->check_utf8 = ret->anchored_utf8;
+               ret->check_utf8 = ret->substrs->data[0].utf8_substr;
            } else {
-               ret->check_utf8 = ret->float_utf8;
+               ret->check_utf8 = ret->substrs->data[1].utf8_substr;
            }
        }
     }
@@ -19864,7 +19861,7 @@ Perl_re_dup_guts(pTHX_ const REGEXP *sstr, REGEXP *dstr, CLONE_PARAMS *param)
               1: a buffer in a different thread
               2: something we no longer hold a reference on
               so we need to copy it locally.  */
-    RX_WRAPPED(dstr) = SAVEPVN(RX_WRAPPED(sstr), SvCUR(sstr)+1);
+    RX_WRAPPED(dstr) = SAVEPVN(RX_WRAPPED_const(sstr), SvCUR(sstr)+1);
     ret->mother_re   = NULL;
 }
 #endif /* PERL_IN_XSUB_RE */