This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
Perl_try_amagic_bin(): eliminate dATARGET
[perl5.git] / toke.c
diff --git a/toke.c b/toke.c
index 6de7d09..5a3fe78 100644 (file)
--- a/toke.c
+++ b/toke.c
@@ -39,6 +39,7 @@ Individual members of C<PL_parser> have their own documentation.
 #define PERL_IN_TOKE_C
 #include "perl.h"
 #include "dquote_inline.h"
+#include "invlist_inline.h"
 
 #define new_constant(a,b,c,d,e,f,g)    \
        S_new_constant(aTHX_ a,b,STR_WITH_LEN(c),d,e,f, g)
@@ -310,6 +311,7 @@ static struct debug_tokens {
     { ANDAND,          TOKENTYPE_NONE,         "ANDAND" },
     { ANDOP,           TOKENTYPE_NONE,         "ANDOP" },
     { ANONSUB,         TOKENTYPE_IVAL,         "ANONSUB" },
+    { ANON_SIGSUB,     TOKENTYPE_IVAL,         "ANON_SIGSUB" },
     { ARROW,           TOKENTYPE_NONE,         "ARROW" },
     { ASSIGNOP,                TOKENTYPE_OPNUM,        "ASSIGNOP" },
     { BITANDOP,                TOKENTYPE_OPNUM,        "BITANDOP" },
@@ -367,6 +369,7 @@ static struct debug_tokens {
     { RELOP,           TOKENTYPE_OPNUM,        "RELOP" },
     { REQUIRE,         TOKENTYPE_NONE,         "REQUIRE" },
     { SHIFTOP,         TOKENTYPE_OPNUM,        "SHIFTOP" },
+    { SIGSUB,          TOKENTYPE_NONE,         "SIGSUB" },
     { SUB,             TOKENTYPE_NONE,         "SUB" },
     { THING,           TOKENTYPE_OPVAL,        "THING" },
     { UMINUS,          TOKENTYPE_NONE,         "UMINUS" },
@@ -456,9 +459,9 @@ S_printbuf(pTHX_ const char *const fmt, const char *const s)
 
     PERL_ARGS_ASSERT_PRINTBUF;
 
-    GCC_DIAG_IGNORE(-Wformat-nonliteral); /* fmt checked by caller */
+    GCC_DIAG_IGNORE_STMT(-Wformat-nonliteral); /* fmt checked by caller */
     PerlIO_printf(Perl_debug_log, fmt, pv_display(tmp, s, strlen(s), 0, 60));
-    GCC_DIAG_RESTORE;
+    GCC_DIAG_RESTORE_STMT;
     SvREFCNT_dec(tmp);
 }
 
@@ -556,16 +559,18 @@ S_no_op(pTHX_ const char *const what, char *s)
  */
 
 STATIC void
-S_missingterm(pTHX_ char *s)
+S_missingterm(pTHX_ char *s, STRLEN len)
 {
     char tmpbuf[UTF8_MAXBYTES + 1];
     char q;
     bool uni = FALSE;
     SV *sv;
     if (s) {
-       char * const nl = strrchr(s,'\n');
-       if (nl)
-           *nl = '\0';
+       char * const nl = (char *) my_memrchr(s, '\n', len);
+        if (nl) {
+            *nl = '\0';
+            len = nl - s;
+        }
        uni = UTF;
     }
     else if (PL_multi_close < 32) {
@@ -573,24 +578,28 @@ S_missingterm(pTHX_ char *s)
        tmpbuf[1] = (char)toCTRL(PL_multi_close);
        tmpbuf[2] = '\0';
        s = tmpbuf;
+        len = 2;
     }
     else {
        if (LIKELY(PL_multi_close < 256)) {
            *tmpbuf = (char)PL_multi_close;
            tmpbuf[1] = '\0';
+            len = 1;
        }
        else {
+            char *end = (char *)uvchr_to_utf8((U8 *)tmpbuf, PL_multi_close);
+            *end = '\0';
+            len = end - tmpbuf;
            uni = TRUE;
-           *uvchr_to_utf8((U8 *)tmpbuf, PL_multi_close) = 0;
        }
        s = tmpbuf;
     }
-    q = strchr(s,'"') ? '\'' : '"';
-    sv = sv_2mortal(newSVpv(s,0));
+    q = memchr(s, '"', len) ? '\'' : '"';
+    sv = sv_2mortal(newSVpvn(s, len));
     if (uni)
        SvUTF8_on(sv);
-    Perl_croak(aTHX_ "Can't find string terminator %c%" SVf
-                    "%c anywhere before EOF",q,SVfARG(sv),q);
+    Perl_croak(aTHX_ "Can't find string terminator %c%" SVf "%c"
+                     " anywhere before EOF", q, SVfARG(sv), q);
 }
 
 #include "feature.h"
@@ -1029,13 +1038,7 @@ Perl_lex_stuff_pvn(pTHX_ const char *pv, STRLEN len, U32 flags)
                SvCUR(PL_parser->linestr) + len+highhalf);
            PL_parser->bufend += len+highhalf;
            for (p = pv; p != e; p++) {
-               U8 c = (U8)*p;
-               if (! UTF8_IS_INVARIANT(c)) {
-                   *bufptr++ = UTF8_TWO_BYTE_HI(c);
-                   *bufptr++ = UTF8_TWO_BYTE_LO(c);
-               } else {
-                   *bufptr++ = (char)c;
-               }
+                append_utf8_from_native_byte(*p, (U8 **) &bufptr);
            }
        }
     } else {
@@ -1572,7 +1575,7 @@ Perl_lex_read_space(pTHX_ U32 flags)
                if (s == bufend)
                    need_incline = 1;
                else
-                   incline(s);
+                   incline(s, bufend);
            }
        } else if (isSPACE(c)) {
            s++;
@@ -1591,7 +1594,7 @@ Perl_lex_read_space(pTHX_ U32 flags)
            if (!got_more)
                break;
            if (can_incline && need_incline && PL_parser->rsfp) {
-               incline(s);
+               incline(s, bufend);
                need_incline = 0;
            }
        } else if (!c) {
@@ -1623,7 +1626,7 @@ Note that C<NULL> is a valid C<proto> and will always return C<true>.
  */
 
 bool
-Perl_validate_proto(pTHX_ SV *name, SV *proto, bool warn)
+Perl_validate_proto(pTHX_ SV *name, SV *proto, bool warn, bool curstash)
 {
     STRLEN len, origlen;
     char *p;
@@ -1685,6 +1688,13 @@ Perl_validate_proto(pTHX_ SV *name, SV *proto, bool warn)
                             origlen, UNI_DISPLAY_ISPRINT)
            : pv_pretty(tmpsv, p, origlen, 60, NULL, NULL, PERL_PV_ESCAPE_NONASCII);
 
+       if (curstash && !memchr(SvPVX(name), ':', SvCUR(name))) {
+           SV *name2 = sv_2mortal(newSVsv(PL_curstname));
+           sv_catpvs(name2, "::");
+           sv_catsv(name2, (SV *)name);
+           name = name2;
+       }
+
        if (proto_after_greedy_proto)
            Perl_warner(aTHX_ packWARN(WARN_ILLEGALPROTO),
                        "Prototype after '%c' for %" SVf " : %s",
@@ -1717,7 +1727,7 @@ Perl_validate_proto(pTHX_ SV *name, SV *proto, bool warn)
  */
 
 STATIC void
-S_incline(pTHX_ const char *s)
+S_incline(pTHX_ const char *s, const char *end)
 {
     const char *t;
     const char *n;
@@ -1727,6 +1737,8 @@ S_incline(pTHX_ const char *s)
 
     PERL_ARGS_ASSERT_INCLINE;
 
+    assert(end >= s);
+
     COPLINE_INC_WITH_HERELINES;
     if (!PL_rsfp && !PL_parser->filtered && PL_lex_state == LEX_NORMAL
      && s+1 == PL_bufend && *s == ';') {
@@ -1738,8 +1750,8 @@ S_incline(pTHX_ const char *s)
        return;
     while (SPACE_OR_TAB(*s))
        s++;
-    if (strEQs(s, "line"))
-       s += 4;
+    if (memBEGINs(s, (STRLEN) (end - s), "line"))
+       s += sizeof("line") - 1;
     else
        return;
     if (SPACE_OR_TAB(*s))
@@ -1758,7 +1770,7 @@ S_incline(pTHX_ const char *s)
        return;
     while (SPACE_OR_TAB(*s))
        s++;
-    if (*s == '"' && (t = strchr(s+1, '"'))) {
+    if (*s == '"' && (t = (char *) memchr(s+1, '"', end - s))) {
        s++;
        e = t + 1;
     }
@@ -1817,14 +1829,14 @@ S_incline(pTHX_ const char *s)
                    }
                    else if (GvAV(cfgv)) {
                        AV * const av = GvAV(cfgv);
-                       const I32 start = CopLINE(PL_curcop)+1;
-                       I32 items = AvFILLp(av) - start;
+                       const line_t start = CopLINE(PL_curcop)+1;
+                       SSize_t items = AvFILLp(av) - start;
                        if (items > 0) {
                            AV * const av2 = GvAVn(gv2);
                            SV **svp = AvARRAY(av) + start;
-                           I32 l = (I32)line_num+1;
-                           while (items--)
-                               av_store(av2, l++, SvREFCNT_inc(*svp++));
+                           Size_t l = line_num+1;
+                           while (items-- && l < SSize_t_MAX && l == (line_t)l)
+                               av_store(av2, (SSize_t)l++, SvREFCNT_inc(*svp++));
                        }
                    }
                }
@@ -1912,7 +1924,6 @@ STATIC void
 S_check_uni(pTHX)
 {
     const char *s;
-    const char *t;
 
     if (PL_oldoldbufptr != PL_last_uni)
        return;
@@ -1921,7 +1932,7 @@ S_check_uni(pTHX)
     s = PL_last_uni;
     while (isWORDCHAR_lazy_if_safe(s, PL_bufend, UTF) || *s == '-')
        s += UTF ? UTF8SKIP(s) : 1;
-    if ((t = strchr(s, '(')) && t < PL_bufptr)
+    if (s < PL_bufptr && memchr(s, '(', PL_bufptr - s))
        return;
 
     Perl_ck_warner_d(aTHX_ packWARN(WARN_AMBIGUOUS),
@@ -2000,7 +2011,7 @@ S_force_next(pTHX_ I32 type)
  * S_postderef
  *
  * This subroutine handles postfix deref syntax after the arrow has already
- * been emitted.  @* $* etc. are emitted as two separate token right here.
+ * been emitted.  @* $* etc. are emitted as two separate tokens right here.
  * @[ @{ %[ %{ *{ are emitted also as two tokens, but this function emits
  * only the first, leaving yylex to find the next.
  */
@@ -2055,10 +2066,9 @@ STATIC SV *
 S_newSV_maybe_utf8(pTHX_ const char *const start, STRLEN len)
 {
     SV * const sv = newSVpvn_utf8(start, len,
-                          !IN_BYTES
-                          && UTF
-                          && !is_utf8_invariant_string((const U8*)start, len)
-                          && is_utf8_string((const U8*)start, len));
+                    ! IN_BYTES
+                  &&  UTF
+                  &&  is_utf8_non_invariant_string((const U8*)start, len));
     return sv;
 }
 
@@ -2096,8 +2106,10 @@ S_force_word(pTHX_ char *start, int token, int check_keyword, int allow_pack)
        if (check_keyword) {
          char *s2 = PL_tokenbuf;
          STRLEN len2 = len;
-         if (allow_pack && len > 6 && strEQs(s2, "CORE::"))
-           s2 += 6, len2 -= 6;
+         if (allow_pack && memBEGINPs(s2, len, "CORE::")) {
+           s2 += sizeof("CORE::") - 1;
+            len2 -= sizeof("CORE::") - 1;
+          }
          if (keyword(s2, len2, 0))
            return start;
        }
@@ -2381,6 +2393,8 @@ S_sublex_start(pTHX)
     PL_parser->lex_super_state = PL_lex_state;
     PL_parser->lex_sub_inwhat = (U16)op_type;
     PL_parser->lex_sub_op = PL_lex_op;
+    PL_parser->sub_no_recover = FALSE;
+    PL_parser->sub_error_count = PL_error_count;
     PL_lex_state = LEX_INTERPPUSH;
 
     PL_expect = XTERM;
@@ -2560,6 +2574,12 @@ S_sublex_done(pTHX)
     else {
        const line_t l = CopLINE(PL_curcop);
        LEAVE;
+        if (PL_parser->sub_error_count != PL_error_count) {
+            if (PL_parser->sub_no_recover) {
+                yyquit();
+                NOT_REACHED;
+            }
+        }
        if (PL_multi_close == '<')
            PL_parser->herelines += l - PL_multi_end;
        PL_bufend = SvPVX(PL_linestr);
@@ -2588,6 +2608,7 @@ S_get_and_check_backslash_N_name(pTHX_ const char* s, const char* const e)
     PERL_ARGS_ASSERT_GET_AND_CHECK_BACKSLASH_N_NAME;
 
     if (!SvCUR(res)) {
+        SvREFCNT_dec_NN(res);
         /* diag_listed_as: Unknown charname '%s' */
         yyerror("Unknown charname ''");
         return NULL;
@@ -2610,8 +2631,7 @@ S_get_and_check_backslash_N_name(pTHX_ const char* s, const char* const e)
         SvTYPE(rv) == SVt_PVCV) && ((stash = CvSTASH(rv)) != NULL))
     {
         const char * const name = HvNAME(stash);
-        if (HvNAMELEN(stash) == sizeof("_charnames")-1
-         && strEQ(name, "_charnames")) {
+         if (memEQs(name, HvNAMELEN(stash), "_charnames")) {
            return res;
        }
     }
@@ -2656,14 +2676,11 @@ S_get_and_check_backslash_N_name(pTHX_ const char* s, const char* const e)
             s += 2;
         }
         else {
-            if (! PL_utf8_charname_begin) {
-                U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
-                PL_utf8_charname_begin = _core_swash_init("utf8",
-                                                        "_Perl_Charname_Begin",
-                                                        &PL_sv_undef,
-                                                        1, 0, NULL, &flags);
-            }
-            if (! swash_fetch(PL_utf8_charname_begin, (U8 *) s, TRUE)) {
+            if (! _invlist_contains_cp(PL_utf8_charname_begin,
+                                       utf8_to_uvchr_buf((U8 *) s,
+                                                         (U8 *) e,
+                                                         NULL)))
+            {
                 goto bad_charname;
             }
             s += UTF8SKIP(s);
@@ -2687,14 +2704,11 @@ S_get_and_check_backslash_N_name(pTHX_ const char* s, const char* const e)
                 s += 2;
             }
             else {
-                if (! PL_utf8_charname_continue) {
-                    U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
-                    PL_utf8_charname_continue = _core_swash_init("utf8",
-                                                "_Perl_Charname_Continue",
-                                                &PL_sv_undef,
-                                                1, 0, NULL, &flags);
-                }
-                if (! swash_fetch(PL_utf8_charname_continue, (U8 *) s, TRUE)) {
+                if (! _invlist_contains_cp(PL_utf8_charname_continue,
+                                           utf8_to_uvchr_buf((U8 *) s,
+                                                             (U8 *) e,
+                                                             NULL)))
+                {
                     goto bad_charname;
                 }
                 s += UTF8SKIP(s);
@@ -2702,6 +2716,9 @@ S_get_and_check_backslash_N_name(pTHX_ const char* s, const char* const e)
         }
     }
     if (*(s-1) == ' ') {
+        /* diag_listed_as: charnames alias definitions may not contain
+                           trailing white-space; marked by <-- HERE in %s
+         */
         yyerror_pv(
             Perl_form(aTHX_
             "charnames alias definitions may not contain trailing "
@@ -2724,6 +2741,8 @@ S_get_and_check_backslash_N_name(pTHX_ const char* s, const char* const e)
                                               (U8 *) PL_parser->bufend,
                                               0,
                                               0 /* 0 means don't die */ );
+            /* diag_listed_as: Malformed UTF-8 returned by \N{%s}
+                               immediately after '%s' */
             yyerror_pv(
               Perl_form(aTHX_
                 "Malformed UTF-8 returned by %.*s immediately after '%.*s'",
@@ -2741,6 +2760,8 @@ S_get_and_check_backslash_N_name(pTHX_ const char* s, const char* const e)
 
         /* The final %.*s makes sure that should the trailing NUL be missing
          * that this print won't run off the end of the string */
+        /* diag_listed_as: Invalid character in \N{...}; marked by <-- HERE
+                           in \N{%s} */
         yyerror_pv(
           Perl_form(aTHX_
             "Invalid character in \\N{...}; marked by <-- HERE in %.*s<-- HERE %.*s",
@@ -2752,6 +2773,9 @@ S_get_and_check_backslash_N_name(pTHX_ const char* s, const char* const e)
     }
 
   multi_spaces:
+        /* diag_listed_as: charnames alias definitions may not contain a
+                           sequence of multiple spaces; marked by <-- HERE
+                           in %s */
         yyerror_pv(
           Perl_form(aTHX_
             "charnames alias definitions may not contain a sequence of "
@@ -2876,8 +2900,8 @@ S_scan_const(pTHX_ char *start)
                                            should we have to convert to
                                            UTF-8) */
     SV *res;                           /* result from charnames */
-    STRLEN offset_to_max;   /* The offset in the output to where the range
-                               high-end character is temporarily placed */
+    STRLEN offset_to_max = 0;   /* The offset in the output to where the range
+                                   high-end character is temporarily placed */
 
     /* Does something require special handling in tr/// ?  This avoids extra
      * work in a less likely case.  As such, khw didn't feel it was worth
@@ -2952,9 +2976,9 @@ S_scan_const(pTHX_ char *start)
 
                 /* Here, we don't think we're in a range.  If the new character
                  * is not a hyphen; or if it is a hyphen, but it's too close to
-                 * either edge to indicate a range, then it's a regular
-                 * character. */
-                if (*s != '-' || s >= send - 1 || s == start) {
+                 * either edge to indicate a range, or if we haven't output any
+                 * characters yet then it's a regular character. */
+                if (*s != '-' || s >= send - 1 || s == start || d == SvPVX(sv)) {
 
                     /* A regular character.  Process like any other, but first
                      * clear any flags */
@@ -3489,7 +3513,8 @@ S_scan_const(pTHX_ char *start)
                {
                    const char* error;
 
-                   bool valid = grok_bslash_o(&s, &uv, &error,
+                   bool valid = grok_bslash_o(&s, PL_bufend,
+                                               &uv, &error,
                                                TRUE, /* Output warning */
                                                FALSE, /* Not strict */
                                                TRUE, /* Output warnings for
@@ -3507,7 +3532,8 @@ S_scan_const(pTHX_ char *start)
                {
                    const char* error;
 
-                   bool valid = grok_bslash_x(&s, &uv, &error,
+                   bool valid = grok_bslash_x(&s, PL_bufend,
+                                               &uv, &error,
                                                TRUE, /* Output warning */
                                                FALSE, /* Not strict */
                                                TRUE,  /* Output warnings for
@@ -3610,11 +3636,12 @@ S_scan_const(pTHX_ char *start)
                  * For non-patterns, the named characters are converted to
                  * their string equivalents.  In patterns, named characters are
                  * not converted to their ultimate forms for the same reasons
-                 * that other escapes aren't.  Instead, they are converted to
-                 * the \N{U+...} form to get the value from the charnames that
-                 * is in effect right now, while preserving the fact that it
-                 * was a named character, so that the regex compiler knows
-                 * this.
+                 * that other escapes aren't (mainly that the ultimate
+                 * character could be considered a meta-symbol by the regex
+                 * compiler).  Instead, they are converted to the \N{U+...}
+                 * form to get the value from the charnames that is in effect
+                 * right now, while preserving the fact that it was a named
+                 * character, so that the regex compiler knows this.
                  *
                 * The structure of this section of code (besides checking for
                 * errors and upgrading to utf8) is:
@@ -3641,7 +3668,7 @@ S_scan_const(pTHX_ char *start)
                s++;
 
                /* If there is no matching '}', it is an error. */
-               if (! (e = strchr(s, '}'))) {
+               if (! (e = (char *) memchr(s, '}', send - s))) {
                    if (! PL_lex_inpat) {
                        yyerror("Missing right brace on \\N{}");
                    } else {
@@ -4120,7 +4147,7 @@ S_scan_const(pTHX_ char *start)
 /* This is the one truly awful dwimmer necessary to conflate C and sed. */
 
 STATIC int
-S_intuit_more(pTHX_ char *s)
+S_intuit_more(pTHX_ char *s, char *e)
 {
     PERL_ARGS_ASSERT_INTUIT_MORE;
 
@@ -4135,6 +4162,7 @@ S_intuit_more(pTHX_ char *s)
        return TRUE;
     if (*s != '{' && *s != '[')
        return FALSE;
+    PL_parser->sub_no_recover = TRUE;
     if (!PL_lex_inpat)
        return TRUE;
 
@@ -4155,7 +4183,7 @@ S_intuit_more(pTHX_ char *s)
         /* this is terrifying, and it works */
        int weight;
        char seen[256];
-       const char * const send = strchr(s,']');
+       const char * const send = (char *) memchr(s, ']', e - s);
        unsigned char un_char, last_un_char;
        char tmpbuf[sizeof PL_tokenbuf * 4];
 
@@ -4426,8 +4454,8 @@ Perl_filter_add(pTHX_ filter_t funcp, SV *datasv)
                    PL_parser->last_uni = buf + last_uni_pos;
                if (PL_parser->last_lop)
                    PL_parser->last_lop = buf + last_lop_pos;
-               SvLEN(linestr) = SvCUR(linestr);
-               SvCUR(linestr) = s-SvPVX(linestr);
+               SvLEN_set(linestr, SvCUR(linestr));
+               SvCUR_set(linestr, s - SvPVX(linestr));
                PL_parser->filtered = 1;
                break;
            }
@@ -4470,6 +4498,7 @@ I32
 Perl_filter_read(pTHX_ int idx, SV *buf_sv, int maxlen)
 {
     filter_t funcp;
+    I32 ret;
     SV *datasv = NULL;
     /* This API is bad. It should have been using unsigned int for maxlen.
        Not sure if we want to change the API, but if not we should sanity
@@ -4552,7 +4581,11 @@ Perl_filter_read(pTHX_ int idx, SV *buf_sv, int maxlen)
     /* Call function. The function is expected to      */
     /* call "FILTER_READ(idx+1, buf_sv)" first.                */
     /* Return: <0:error, =0:eof, >0:not eof            */
-    return (*funcp)(aTHX_ idx, buf_sv, correct_length);
+    ENTER;
+    save_scalar(PL_errgv);
+    ret = (*funcp)(aTHX_ idx, buf_sv, correct_length);
+    LEAVE;
+    return ret;
 }
 
 STATIC char *
@@ -4584,7 +4617,7 @@ S_find_in_my_stash(pTHX_ const char *pkgname, STRLEN len)
 
     PERL_ARGS_ASSERT_FIND_IN_MY_STASH;
 
-    if (len == 11 && *pkgname == '_' && strEQ(pkgname, "__PACKAGE__"))
+    if (memEQs(pkgname, len, "__PACKAGE__"))
         return PL_curstash;
 
     if (len > 2
@@ -4613,6 +4646,7 @@ S_tokenize_use(pTHX_ int is_use, char *s) {
     PERL_ARGS_ASSERT_TOKENIZE_USE;
 
     if (PL_expect != XSTATE)
+       /* diag_listed_as: "use" not allowed in expression */
        yyerror(Perl_form(aTHX_ "\"%s\" not allowed in expression",
                    is_use ? "use" : "no"));
     PL_expect = XTERM;
@@ -4858,8 +4892,11 @@ Perl_yylex(pTHX)
            }
            else {
                I32 tmp;
-                if (strnEQ(s, "L\\u", 3) || strnEQ(s, "U\\l", 3))
+                if (   memBEGINs(s, (STRLEN) (PL_bufend - s), "L\\u")
+                    || memBEGINs(s, (STRLEN) (PL_bufend - s), "U\\l"))
+                {
                     tmp = *s, *s = s[2], s[2] = (char)tmp;     /* misordered... */
+                }
                if ((*s == 'L' || *s == 'U' || *s == 'F')
                     && (strpbrk(PL_lex_casestack, "LUF")))
                 {
@@ -4950,7 +4987,7 @@ Perl_yylex(pTHX)
        return yylex();
 
     case LEX_INTERPENDMAYBE:
-       if (intuit_more(PL_bufptr)) {
+       if (intuit_more(PL_bufptr, PL_bufend)) {
            PL_lex_state = LEX_INTERPNORMAL;    /* false alarm, more expr */
            break;
        }
@@ -5054,6 +5091,15 @@ Perl_yylex(pTHX)
 
        return yylex();
     case LEX_FORMLINE:
+        if (PL_parser->sub_error_count != PL_error_count) {
+            /* There was an error parsing a formline, which tends to
+               mess up the parser.
+               Unlike interpolated sub-parsing, we can't treat any of
+               these as recoverable, so no need to check sub_no_recover.
+            */
+            yyquit();
+        }
+       assert(PL_lex_formbrack);
        s = scan_formline(PL_bufptr);
        if (!PL_lex_formbrack)
        {
@@ -5104,15 +5150,46 @@ Perl_yylex(pTHX)
                 /* read var name, including sigil, into PL_tokenbuf */
                 PL_tokenbuf[0] = sigil;
                 parse_ident(&s, &dest, dest + sizeof(PL_tokenbuf) - 1,
-                    0, cBOOL(UTF), FALSE);
+                    0, cBOOL(UTF), FALSE, FALSE);
                 *dest = '\0';
                 assert(PL_tokenbuf[1]); /* we have a variable name */
+            }
+            else {
+                *PL_tokenbuf = 0;
+                PL_in_my = 0;
+            }
+
+            s = skipspace(s);
+            /* parse the = for the default ourselves to avoid '+=' etc being accepted here
+             * as the ASSIGNOP, and exclude other tokens that start with =
+             */
+            if (*s == '=' && (!s[1] || strchr("=~>", s[1]) == 0)) {
+                /* save now to report with the same context as we did when
+                 * all ASSIGNOPS were accepted */
+                PL_oldbufptr = s;
+
+                ++s;
+                NEXTVAL_NEXTTOKE.ival = 0;
+                force_next(ASSIGNOP);
+                PL_expect = XTERM;
+            }
+            else if (*s == ',' || *s == ')') {
+                PL_expect = XOPERATOR;
+            }
+            else {
+                /* make sure the context shows the unexpected character and
+                 * hopefully a bit more */
+                if (*s) ++s;
+                while (*s && *s != '$' && *s != '@' && *s != '%' && *s != ')')
+                    s++;
+                PL_bufptr = s; /* for error reporting */
+                yyerror("Illegal operator following parameter in a subroutine signature");
+                PL_in_my = 0;
+            }
+            if (*PL_tokenbuf) {
                 NEXTVAL_NEXTTOKE.ival = sigil;
                 force_next('p'); /* force a signature pending identifier */
             }
-            else
-                PL_in_my = 0;
-            PL_expect = XOPERATOR;
             break;
 
         case ')':
@@ -5158,12 +5235,23 @@ Perl_yylex(pTHX)
         else {
             c = Perl_form(aTHX_ "\\x%02X", (unsigned char)*s);
         }
-        len = UTF ? Perl_utf8_length(aTHX_ (U8 *) PL_linestart, (U8 *) s) : (STRLEN) (s - PL_linestart);
-        if (len > UNRECOGNIZED_PRECEDE_COUNT) {
-            d = UTF ? (char *) utf8_hop_back((U8 *) s, -UNRECOGNIZED_PRECEDE_COUNT, (U8 *)PL_linestart) : s - UNRECOGNIZED_PRECEDE_COUNT;
-        } else {
+
+        if (s >= PL_linestart) {
             d = PL_linestart;
         }
+        else {
+            /* somehow (probably due to a parse failure), PL_linestart has advanced
+             * pass PL_bufptr, get a reasonable beginning of line
+             */
+            d = s;
+            while (d > SvPVX(PL_linestr) && d[-1] && d[-1] != '\n')
+                --d;
+        }
+        len = UTF ? Perl_utf8_length(aTHX_ (U8 *) d, (U8 *) s) : (STRLEN) (s - d);
+        if (len > UNRECOGNIZED_PRECEDE_COUNT) {
+            d = UTF ? (char *) utf8_hop_back((U8 *) s, -UNRECOGNIZED_PRECEDE_COUNT, (U8 *)d) : s - UNRECOGNIZED_PRECEDE_COUNT;
+        }
+
         Perl_croak(aTHX_  "Unrecognized character %s; marked by <-- HERE after %" UTF8f "<-- HERE near column %d", c,
                           UTF8fARG(UTF, (s - d), d),
                          (int) len + 1);
@@ -5232,10 +5320,15 @@ Perl_yylex(pTHX)
                    sv_catpvs(PL_linestr,"chomp;");
                if (PL_minus_a) {
                    if (PL_minus_F) {
-                       if ((*PL_splitstr == '/' || *PL_splitstr == '\''
-                            || *PL_splitstr == '"')
-                             && strchr(PL_splitstr + 1, *PL_splitstr))
+                        if (   (   *PL_splitstr == '/'
+                                || *PL_splitstr == '\''
+                                || *PL_splitstr == '"')
+                            && strchr(PL_splitstr + 1, *PL_splitstr))
+                        {
+                            /* strchr is ok, because -F pattern can't contain
+                             * embeddded NULs */
                            Perl_sv_catpvf(aTHX_ PL_linestr, "our @F=split(%s);", PL_splitstr);
+                        }
                        else {
                            /* "q\0${splitstr}\0" is legal perl. Yes, even NUL
                               bytes can be used as quoting characters.  :-) */
@@ -5284,10 +5377,10 @@ Perl_yylex(pTHX)
            /* If it looks like the start of a BOM or raw UTF-16,
             * check if it in fact is. */
            if (bof && PL_rsfp
-                && (*s == 0
+                && (   *s == 0
                     || *(U8*)s == BOM_UTF8_FIRST_BYTE
-                        || *(U8*)s >= 0xFE
-                        || s[1] == 0))
+                    || *(U8*)s >= 0xFE
+                    || s[1] == 0))
             {
                Off_t offset = (IV)PerlIO_tell(PL_rsfp);
                bof = (offset == (Off_t)SvCUR(PL_linestr));
@@ -5303,7 +5396,9 @@ Perl_yylex(pTHX)
            }
            if (PL_parser->in_pod) {
                /* Incest with pod. */
-               if (*s == '=' && strEQs(s, "=cut") && !isALPHA(s[4])) {
+                if (    memBEGINPs(s, (STRLEN) (PL_bufend - s), "=cut")
+                    && !isALPHA(s[4]))
+                {
                     SvPVCLEAR(PL_linestr);
                    PL_oldoldbufptr = PL_oldbufptr = s = PL_linestart = SvPVX(PL_linestr);
                    PL_bufend = SvPVX(PL_linestr) + SvCUR(PL_linestr);
@@ -5312,7 +5407,7 @@ Perl_yylex(pTHX)
                }
            }
            if (PL_rsfp || PL_parser->filtered)
-               incline(s);
+               incline(s, PL_bufend);
        } while (PL_parser->in_pod);
        PL_oldoldbufptr = PL_oldbufptr = PL_bufptr = PL_linestart = s;
        PL_bufend = SvPVX(PL_linestr) + SvCUR(PL_linestr);
@@ -5537,24 +5632,20 @@ Perl_yylex(pTHX)
             && !PL_rsfp && !PL_parser->filtered) {
                /* handle eval qq[#line 1 "foo"\n ...] */
                CopLINE_dec(PL_curcop);
-               incline(s);
+               incline(s, PL_bufend);
            }
             d = s;
             while (d < PL_bufend && *d != '\n')
                 d++;
             if (d < PL_bufend)
                 d++;
-            else if (d > PL_bufend)
-                /* Found by Ilya: feed random input to Perl. */
-                Perl_croak(aTHX_ "panic: input overflow, %p > %p",
-                           d, PL_bufend);
             s = d;
             if (in_comment && d == PL_bufend
                 && PL_lex_state == LEX_INTERPNORMAL
                 && PL_lex_inwhat == OP_SUBST && PL_lex_repl == PL_linestr
                 && SvEVALED(PL_lex_repl) && d[-1] == '}') s--;
             else
-                incline(s);
+                incline(s, PL_bufend);
            if (PL_lex_formbrack && PL_lex_brackets <= PL_lex_formbrack) {
                PL_lex_state = LEX_FORMLINE;
                force_next(FORMRBRACK);
@@ -5568,11 +5659,8 @@ Perl_yylex(pTHX)
                 {
                     s++;
                     if (s < PL_bufend)
-                        incline(s);
+                        incline(s, PL_bufend);
                 }
-            else if (s > PL_bufend)
-                /* Found by Ilya: feed random input to Perl. */
-                Perl_croak(aTHX_ "panic: input overflow");
        }
        goto retry;
     case '-':
@@ -5587,7 +5675,7 @@ Perl_yylex(pTHX)
            while (s < PL_bufend && SPACE_OR_TAB(*s))
                s++;
 
-           if (strEQs(s,"=>")) {
+           if (memBEGINs(s, (STRLEN) (PL_bufend - s), "=>")) {
                s = force_word(PL_bufptr,BAREWORD,FALSE,FALSE);
                DEBUG_T( { printbuf("### Saw unary minus before =>, forcing word %s\n", s); } );
                OPERATOR('-');          /* unary minus */
@@ -5772,7 +5860,8 @@ Perl_yylex(pTHX)
        if (!PL_tokenbuf[1]) {
            PREREF('%');
        }
-       if ((PL_expect != XREF || PL_oldoldbufptr == PL_last_lop) && intuit_more(s)) {
+        if (   (PL_expect != XREF || PL_oldoldbufptr == PL_last_lop)
+            && intuit_more(s, PL_bufend)) {
            if (*s == '[')
                PL_tokenbuf[0] = '@';
        }
@@ -5850,9 +5939,17 @@ Perl_yylex(pTHX)
        case XATTRTERM:
            PL_expect = XTERMBLOCK;
         grabattrs:
+            /* NB: as well as parsing normal attributes, we also end up
+             * here if there is something looking like attributes
+             * following a signature (which is illegal, but used to be
+             * legal in 5.20..5.26). If the latter, we still parse the
+             * attributes so that error messages(s) are less confusing,
+             * but ignore them (parser->sig_seen).
+             */
            s = skipspace(s);
            attrs = NULL;
             while (isIDFIRST_lazy_if_safe(s, PL_bufend, UTF)) {
+                bool sig = PL_parser->sig_seen;
                I32 tmp;
                SV *sv;
                d = scan_word(s, PL_tokenbuf, sizeof PL_tokenbuf, FALSE, &len);
@@ -5893,26 +5990,29 @@ Perl_yylex(pTHX)
                else {
                    /* NOTE: any CV attrs applied here need to be part of
                       the CVf_BUILTIN_ATTRS define in cv.h! */
-                   if (!PL_in_my && len == 6 && strnEQ(SvPVX(sv), "lvalue", len)) {
+                   if (!PL_in_my && memEQs(SvPVX(sv), len, "lvalue")) {
                        sv_free(sv);
-                       CvLVALUE_on(PL_compcv);
+                       if (!sig)
+                            CvLVALUE_on(PL_compcv);
                    }
-                   else if (!PL_in_my && len == 6 && strnEQ(SvPVX(sv), "method", len)) {
+                   else if (!PL_in_my && memEQs(SvPVX(sv), len, "method")) {
                        sv_free(sv);
-                       CvMETHOD_on(PL_compcv);
+                       if (!sig)
+                            CvMETHOD_on(PL_compcv);
                    }
-                   else if (!PL_in_my && len == 5
-                         && strnEQ(SvPVX(sv), "const", len))
+                   else if (!PL_in_my && memEQs(SvPVX(sv), len, "const"))
                    {
                        sv_free(sv);
-                       Perl_ck_warner_d(aTHX_
-                           packWARN(WARN_EXPERIMENTAL__CONST_ATTR),
-                          ":const is experimental"
-                       );
-                       CvANONCONST_on(PL_compcv);
-                       if (!CvANON(PL_compcv))
-                           yyerror(":const is not permitted on named "
-                                   "subroutines");
+                        if (!sig) {
+                            Perl_ck_warner_d(aTHX_
+                                packWARN(WARN_EXPERIMENTAL__CONST_ATTR),
+                               ":const is experimental"
+                            );
+                            CvANONCONST_on(PL_compcv);
+                            if (!CvANON(PL_compcv))
+                                yyerror(":const is not permitted on named "
+                                        "subroutines");
+                        }
                    }
                    /* After we've set the flags, it could be argued that
                       we don't need to do the attributes.pm-based setting
@@ -5965,6 +6065,14 @@ Perl_yylex(pTHX)
                }
            }
        got_attrs:
+            if (PL_parser->sig_seen) {
+                /* see comment about about sig_seen and parser error
+                 * handling */
+                if (attrs)
+                    op_free(attrs);
+                Perl_croak(aTHX_ "Subroutine attributes must come "
+                                 "before the signature");
+                }
            if (attrs) {
                NEXTVAL_NEXTTOKE.opval = attrs;
                force_next(THING);
@@ -6199,9 +6307,11 @@ Perl_yylex(pTHX)
                        PL_expect = XTERM;
                        break;
                    }
-                   if (strEQs(s, "sub")) {
+                   if (memBEGINs(s, (STRLEN) (PL_bufend - s), "sub")) {
+                        PL_bufptr = s;
                        d = s + 3;
                        d = skipspace(d);
+                        s = PL_bufptr;
                        if (*d == ':') {
                            PL_expect = XTERM;
                            break;
@@ -6223,6 +6333,7 @@ Perl_yylex(pTHX)
        if (PL_lex_brackets && PL_lex_brackstack[PL_lex_brackets-1] == XFAKEEOF)
            TOKEN(0);
       rightbracket:
+       assert(s != PL_bufend);
        s++;
        if (PL_lex_brackets <= 0)
            /* diag_listed_as: Unmatched right %s bracket */
@@ -6253,7 +6364,7 @@ Perl_yylex(pTHX)
            return yylex();             /* ignore fake brackets */
        }
        force_next(formbrack ? '.' : '}');
-       if (formbrack) LEAVE;
+       if (formbrack) LEAVE_with_name("lex_format");
        if (formbrack == 2) { /* means . where arguments were expected */
            force_next(';');
            TOKEN(FORMRBRACK);
@@ -6332,7 +6443,9 @@ Perl_yylex(pTHX)
        {
            const char tmp = *s++;
            if (tmp == '=') {
-               if ((s == PL_linestart+2 || s[-3] == '\n') && strEQs(s, "=====")) {
+                if (   (s == PL_linestart+2 || s[-3] == '\n')
+                    && memBEGINs(s, (STRLEN) (PL_bufend - s), "====="))
+                {
                    s = vcs_conflict_marker(s + 5);
                    goto retry;
                }
@@ -6364,19 +6477,21 @@ Perl_yylex(pTHX)
                 && isALPHA(tmp)
                 && (s == PL_linestart+1 || s[-2] == '\n') )
             {
-                if ((PL_in_eval && !PL_rsfp && !PL_parser->filtered)
-                    || PL_lex_state != LEX_NORMAL) {
+                if (   (PL_in_eval && !PL_rsfp && !PL_parser->filtered)
+                    || PL_lex_state != LEX_NORMAL)
+                {
                     d = PL_bufend;
                     while (s < d) {
                         if (*s++ == '\n') {
-                            incline(s);
-                            if (strEQs(s,"=cut")) {
-                                s = strchr(s,'\n');
+                            incline(s, PL_bufend);
+                            if (memBEGINs(s, (STRLEN) (PL_bufend - s), "=cut"))
+                            {
+                                s = (char *) memchr(s,'\n', d - s);
                                 if (s)
                                     s++;
                                 else
                                     s = d;
-                                incline(s);
+                                incline(s, PL_bufend);
                                 goto retry;
                             }
                         }
@@ -6398,11 +6513,12 @@ Perl_yylex(pTHX)
                t++;
            if (*t == '\n' || *t == '#') {
                formbrack = 1;
-               ENTER;
+               ENTER_with_name("lex_format");
                SAVEI8(PL_parser->form_lex_state);
                SAVEI32(PL_lex_formbrack);
                PL_parser->form_lex_state = PL_lex_state;
                PL_lex_formbrack = PL_lex_brackets + 1;
+                PL_parser->sub_error_count = PL_error_count;
                goto leftbracket;
            }
        }
@@ -6448,10 +6564,12 @@ Perl_yylex(pTHX)
        OPERATOR('!');
     case '<':
        if (PL_expect != XOPERATOR) {
-           if (s[1] != '<' && !strchr(s,'>'))
+           if (s[1] != '<' && !memchr(s,'>', PL_bufend - s))
                check_uni();
            if (s[1] == '<' && s[2] != '>') {
-               if ((s == PL_linestart || s[-1] == '\n') && strEQs(s+2, "<<<<<")) {
+                if (   (s == PL_linestart || s[-1] == '\n')
+                    && memBEGINs(s+2, (STRLEN) (PL_bufend - (s+2)), "<<<<<"))
+                {
                    s = vcs_conflict_marker(s + 7);
                    goto retry;
                }
@@ -6466,7 +6584,9 @@ Perl_yylex(pTHX)
        {
            char tmp = *s++;
            if (tmp == '<') {
-               if ((s == PL_linestart+2 || s[-3] == '\n') && strEQs(s, "<<<<<")) {
+                if (   (s == PL_linestart+2 || s[-3] == '\n')
+                    && memBEGINs(s, (STRLEN) (PL_bufend - s), "<<<<<"))
+                {
                     s = vcs_conflict_marker(s + 5);
                    goto retry;
                }
@@ -6510,7 +6630,9 @@ Perl_yylex(pTHX)
        {
            const char tmp = *s++;
            if (tmp == '>') {
-               if ((s == PL_linestart+2 || s[-3] == '\n') && strEQs(s, ">>>>>")) {
+               if (   (s == PL_linestart+2 || s[-3] == '\n')
+                    && memBEGINs(s, (STRLEN) (PL_bufend - s), ">>>>>"))
+                {
                    s = vcs_conflict_marker(s + 5);
                    goto retry;
                }
@@ -6594,8 +6716,8 @@ Perl_yylex(pTHX)
            if (PL_lex_state == LEX_NORMAL || PL_lex_brackets)
                s = skipspace(s);
 
-           if ((PL_expect != XREF || PL_oldoldbufptr == PL_last_lop)
-               && intuit_more(s)) {
+           if (   (PL_expect != XREF || PL_oldoldbufptr == PL_last_lop)
+               && intuit_more(s, PL_bufend)) {
                if (*s == '[') {
                    PL_tokenbuf[0] = '@';
                    if (ckWARN(WARN_SYNTAX)) {
@@ -6620,30 +6742,32 @@ Perl_yylex(pTHX)
                else if (*s == '{') {
                    char *t;
                    PL_tokenbuf[0] = '%';
-                   if (strEQ(PL_tokenbuf+1, "SIG")  && ckWARN(WARN_SYNTAX)
-                       && (t = strchr(s, '}')) && (t = strchr(t, '=')))
-                       {
-                           char tmpbuf[sizeof PL_tokenbuf];
-                           do {
-                               t++;
-                           } while (isSPACE(*t));
-                           if (isIDFIRST_lazy_if_safe(t, PL_bufend, UTF)) {
-                               STRLEN len;
-                               t = scan_word(t, tmpbuf, sizeof tmpbuf, TRUE,
-                                             &len);
-                               while (isSPACE(*t))
-                                   t++;
-                                if (  *t == ';'
-                                    && get_cvn_flags(tmpbuf, len, UTF
-                                                                  ? SVf_UTF8
-                                                                  : 0))
-                                {
-                                   Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
-                                       "You need to quote \"%" UTF8f "\"",
-                                        UTF8fARG(UTF, len, tmpbuf));
-                                }
-                           }
-                       }
+                    if (    strEQ(PL_tokenbuf+1, "SIG")
+                        && ckWARN(WARN_SYNTAX)
+                        && (t = (char *) memchr(s, '}', PL_bufend - s))
+                        && (t = (char *) memchr(t, '=', PL_bufend - t)))
+                    {
+                        char tmpbuf[sizeof PL_tokenbuf];
+                        do {
+                            t++;
+                        } while (isSPACE(*t));
+                        if (isIDFIRST_lazy_if_safe(t, PL_bufend, UTF)) {
+                            STRLEN len;
+                            t = scan_word(t, tmpbuf, sizeof tmpbuf, TRUE,
+                                            &len);
+                            while (isSPACE(*t))
+                                t++;
+                            if (  *t == ';'
+                                && get_cvn_flags(tmpbuf, len, UTF
+                                                                ? SVf_UTF8
+                                                                : 0))
+                            {
+                                Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
+                                    "You need to quote \"%" UTF8f "\"",
+                                        UTF8fARG(UTF, len, tmpbuf));
+                            }
+                        }
+                    }
                }
            }
 
@@ -6723,7 +6847,9 @@ Perl_yylex(pTHX)
        }
        if (PL_lex_state == LEX_NORMAL)
            s = skipspace(s);
-       if ((PL_expect != XREF || PL_oldoldbufptr == PL_last_lop) && intuit_more(s)) {
+       if (   (PL_expect != XREF || PL_oldoldbufptr == PL_last_lop)
+            && intuit_more(s, PL_bufend))
+        {
            if (*s == '{')
                PL_tokenbuf[0] = '%';
 
@@ -6834,7 +6960,7 @@ Perl_yylex(pTHX)
     case '\'':
        s = scan_str(s,FALSE,FALSE,FALSE,NULL);
        if (!s)
-           missingterm(NULL);
+           missingterm(NULL, 0);
        COPLINE_SET_FROM_MULTI_END;
        DEBUG_T( { printbuf("### Saw string before %s\n", s); } );
        if (PL_expect == XOPERATOR) {
@@ -6856,7 +6982,7 @@ Perl_yylex(pTHX)
                no_op("String",s);
        }
        if (!s)
-           missingterm(NULL);
+           missingterm(NULL, 0);
        pl_yylval.ival = OP_CONST;
        /* FIXME. I think that this can be const if char *d is replaced by
           more localised variables.  */
@@ -6882,7 +7008,7 @@ Perl_yylex(pTHX)
        if (PL_expect == XOPERATOR)
            no_op("Backticks",s);
        if (!s)
-           missingterm(NULL);
+           missingterm(NULL, 0);
        pl_yylval.ival = OP_BACKTICK;
        TERM(sublex_start());
 
@@ -6987,7 +7113,7 @@ Perl_yylex(pTHX)
 
        /* x::* is just a word, unless x is "CORE" */
        if (!anydelim && *s == ':' && s[1] == ':') {
-           if (strEQ(PL_tokenbuf, "CORE")) goto case_KEY_CORE;
+           if (memEQs(PL_tokenbuf, len, "CORE")) goto case_KEY_CORE;
            goto just_a_word;
        }
 
@@ -7123,10 +7249,7 @@ Perl_yylex(pTHX)
            else {                      /* no override */
                tmp = -tmp;
                if (tmp == KEY_dump) {
-                   Perl_ck_warner_d(aTHX_ packWARN2(WARN_MISC,WARN_DEPRECATED),
-                                    "dump() better written as CORE::dump(). "
-                                     "dump() will no longer be available "
-                                     "in Perl 5.30");
+                   Perl_croak(aTHX_ "dump() must be written as CORE::dump() as of Perl 5.30");
                }
                gv = NULL;
                gvp = 0;
@@ -7169,12 +7292,26 @@ Perl_yylex(pTHX)
                orig_keyword = 0;
                lex = 0;
                off = 0;
+            /* FALLTHROUGH */
        default:                        /* not a keyword */
          just_a_word: {
                int pkgname = 0;
                const char lastchar = (PL_bufptr == PL_oldoldbufptr ? 0 : PL_bufptr[-1]);
                bool safebw;
+               bool no_op_error = FALSE;
 
+               if (PL_expect == XOPERATOR) {
+                   if (PL_bufptr == PL_linestart) {
+                       CopLINE_dec(PL_curcop);
+                       Perl_warner(aTHX_ packWARN(WARN_SEMICOLON), "%s", PL_warn_nosemi);
+                       CopLINE_inc(PL_curcop);
+                   }
+                   else
+                       /* We want to call no_op with s pointing after the
+                          bareword, so defer it.  But we want it to come
+                          before the Bad name croak.  */
+                       no_op_error = TRUE;
+               }
 
                /* Get the rest if it looks like a package qualifier */
 
@@ -7182,6 +7319,10 @@ Perl_yylex(pTHX)
                    STRLEN morelen;
                    s = scan_word(s, PL_tokenbuf + len, sizeof PL_tokenbuf - len,
                                  TRUE, &morelen);
+                   if (no_op_error) {
+                       no_op("Bareword",s);
+                       no_op_error = FALSE;
+                   }
                    if (!morelen)
                        Perl_croak(aTHX_ "Bad name after %" UTF8f "%s",
                                UTF8fARG(UTF, len, PL_tokenbuf),
@@ -7190,15 +7331,8 @@ Perl_yylex(pTHX)
                    pkgname = 1;
                }
 
-               if (PL_expect == XOPERATOR) {
-                   if (PL_bufptr == PL_linestart) {
-                       CopLINE_dec(PL_curcop);
-                       Perl_warner(aTHX_ packWARN(WARN_SEMICOLON), "%s", PL_warn_nosemi);
-                       CopLINE_inc(PL_curcop);
-                   }
-                   else
+               if (no_op_error)
                        no_op("Bareword",s);
-               }
 
                /* See if the name is "Foo::",
                   in which case Foo is a bareword
@@ -7509,10 +7643,10 @@ Perl_yylex(pTHX)
                            if (!*d && !gv_stashpv(PL_tokenbuf, UTF ? SVf_UTF8 : 0))
                             {
                                 /* PL_warn_reserved is constant */
-                                GCC_DIAG_IGNORE(-Wformat-nonliteral);
+                                GCC_DIAG_IGNORE_STMT(-Wformat-nonliteral);
                                Perl_warner(aTHX_ packWARN(WARN_RESERVED), PL_warn_reserved,
                                       PL_tokenbuf);
-                                GCC_DIAG_RESTORE;
+                                GCC_DIAG_RESTORE_STMT;
                             }
                        }
                    }
@@ -7567,14 +7701,6 @@ Perl_yylex(pTHX)
                if (!GvIO(gv))
                    GvIOp(gv) = newIO();
                IoIFP(GvIOp(gv)) = PL_rsfp;
-#if defined(HAS_FCNTL) && defined(F_SETFD) && defined(FD_CLOEXEC)
-               {
-                   const int fd = PerlIO_fileno(PL_rsfp);
-                    if (fd >= 3) {
-                        fcntl(fd,F_SETFD, FD_CLOEXEC);
-                    }
-               }
-#endif
                /* Mark this internal pseudo-handle as clean */
                IoFLAGS(GvIOp(gv)) |= IOf_UNTAINT;
                if ((PerlIO*)PL_rsfp == PerlIO_stdin())
@@ -7759,7 +7885,7 @@ Perl_yylex(pTHX)
                *PL_tokenbuf = '&';
                d = scan_word(s, PL_tokenbuf + 1, sizeof PL_tokenbuf - 1,
                              1, &len);
-               if (len && (len != 4 || strNE(PL_tokenbuf+1, "CORE"))
+               if (len && memNEs(PL_tokenbuf+1, len, "CORE")
                 && !keyword(PL_tokenbuf + 1, len, 0)) {
                     SSize_t off = s-SvPVX(PL_linestr);
                    d = skipspace(d);
@@ -7879,14 +8005,17 @@ Perl_yylex(pTHX)
                char *p = s;
                 SSize_t s_off = s - SvPVX(PL_linestr);
 
-               if ((PL_bufend - p) >= 3
-                    && strEQs(p, "my") && isSPACE(*(p + 2)))
+                if (   memBEGINPs(p, (STRLEN) (PL_bufend - p), "my")
+                    && isSPACE(*(p + 2)))
                 {
-                   p += 2;
+                    p += 2;
+                }
+                else if (   memBEGINPs(p, (STRLEN) (PL_bufend - p), "our")
+                         && isSPACE(*(p + 3)))
+                {
+                    p += 3;
                 }
-               else if ((PL_bufend - p) >= 4
-                         && strEQs(p, "our") && isSPACE(*(p + 3)))
-                   p += 3;
+
                p = skipspace(p);
                 /* skip optional package name, as in "for my abc $x (..)" */
                if (isIDFIRST_lazy_if_safe(p, PL_bufend, UTF)) {
@@ -8137,7 +8266,7 @@ Perl_yylex(pTHX)
            s = skipspace(s);
             if (isIDFIRST_lazy_if_safe(s, PL_bufend, UTF)) {
                s = scan_word(s, PL_tokenbuf, sizeof PL_tokenbuf, TRUE, &len);
-               if (len == 3 && strEQs(PL_tokenbuf, "sub"))
+               if (memEQs(PL_tokenbuf, len, "sub"))
                    goto really_sub;
                PL_in_my_stash = find_in_my_stash(PL_tokenbuf, len);
                if (!PL_in_my_stash) {
@@ -8254,7 +8383,7 @@ Perl_yylex(pTHX)
        case KEY_q:
            s = scan_str(s,FALSE,FALSE,FALSE,NULL);
            if (!s)
-               missingterm(NULL);
+               missingterm(NULL, 0);
            COPLINE_SET_FROM_MULTI_END;
            pl_yylval.ival = OP_CONST;
            TERM(sublex_start());
@@ -8266,7 +8395,7 @@ Perl_yylex(pTHX)
            OP *words = NULL;
            s = scan_str(s,FALSE,FALSE,FALSE,NULL);
            if (!s)
-               missingterm(NULL);
+               missingterm(NULL, 0);
            COPLINE_SET_FROM_MULTI_END;
            PL_expect = XOPERATOR;
            if (SvCUR(PL_lex_stuff)) {
@@ -8315,7 +8444,7 @@ Perl_yylex(pTHX)
        case KEY_qq:
            s = scan_str(s,FALSE,FALSE,FALSE,NULL);
            if (!s)
-               missingterm(NULL);
+               missingterm(NULL, 0);
            pl_yylval.ival = OP_STRINGIFY;
            if (SvIVX(PL_lex_stuff) == '\'')
                SvIV_set(PL_lex_stuff, 0);      /* qq'$foo' should interpolate */
@@ -8328,7 +8457,7 @@ Perl_yylex(pTHX)
        case KEY_qx:
            s = scan_str(s,FALSE,FALSE,FALSE,NULL);
            if (!s)
-               missingterm(NULL);
+               missingterm(NULL, 0);
            pl_yylval.ival = OP_BACKTICK;
            TERM(sublex_start());
 
@@ -8544,22 +8673,24 @@ Perl_yylex(pTHX)
          really_sub:
            {
                char * const tmpbuf = PL_tokenbuf + 1;
-               expectation attrful;
                bool have_name, have_proto;
                const int key = tmp;
                 SV *format_name = NULL;
+                bool is_sigsub = FEATURE_SIGNATURES_IS_ENABLED;
 
                 SSize_t off = s-SvPVX(PL_linestr);
                s = skipspace(s);
                 d = SvPVX(PL_linestr)+off;
 
+                SAVEBOOL(PL_parser->sig_seen);
+                PL_parser->sig_seen = FALSE;
+
                 if (   isIDFIRST_lazy_if_safe(s, PL_bufend, UTF)
                     || *s == '\''
                     || (*s == ':' && s[1] == ':'))
                {
 
-                   PL_expect = XBLOCK;
-                   attrful = XATTRBLOCK;
+                   PL_expect = XATTRBLOCK;
                    d = scan_word(s, tmpbuf, sizeof PL_tokenbuf - 1, TRUE,
                                  &len);
                     if (key == KEY_format)
@@ -8590,8 +8721,7 @@ Perl_yylex(pTHX)
                        Perl_croak(aTHX_
                                  "Missing name in \"%s\"", PL_bufptr);
                    }
-                   PL_expect = XTERMBLOCK;
-                   attrful = XATTRTERM;
+                   PL_expect = XATTRTERM;
                    sv_setpvs(PL_subname,"?");
                    have_name = FALSE;
                }
@@ -8607,12 +8737,13 @@ Perl_yylex(pTHX)
                }
 
                /* Look for a prototype */
-               if (*s == '(' && !FEATURE_SIGNATURES_IS_ENABLED) {
+               if (*s == '(' && !is_sigsub) {
                    s = scan_str(s,FALSE,FALSE,FALSE,NULL);
-                   COPLINE_SET_FROM_MULTI_END;
                    if (!s)
                        Perl_croak(aTHX_ "Prototype not terminated");
-                   (void)validate_proto(PL_subname, PL_lex_stuff, ckWARN(WARN_ILLEGALPROTO));
+                   COPLINE_SET_FROM_MULTI_END;
+                   (void)validate_proto(PL_subname, PL_lex_stuff,
+                                        ckWARN(WARN_ILLEGALPROTO), 0);
                    have_proto = TRUE;
 
                    s = skipspace(s);
@@ -8620,9 +8751,9 @@ Perl_yylex(pTHX)
                else
                    have_proto = FALSE;
 
-               if (*s == ':' && s[1] != ':')
-                   PL_expect = attrful;
-               else if ((*s != '{' && *s != '(') && key != KEY_format) {
+               if (  !(*s == ':' && s[1] != ':')
+                    && (*s != '{' && *s != '(') && key != KEY_format)
+                {
                     assert(key == KEY_sub || key == KEY_AUTOLOAD ||
                            key == KEY_DESTROY || key == KEY_BEGIN ||
                            key == KEY_UNITCHECK || key == KEY_CHECK ||
@@ -8646,10 +8777,16 @@ Perl_yylex(pTHX)
                        sv_setpvs(PL_subname, "__ANON__");
                    else
                        sv_setpvs(PL_subname, "__ANON__::__ANON__");
-                   TOKEN(ANONSUB);
+                    if (is_sigsub)
+                        TOKEN(ANON_SIGSUB);
+                    else
+                        TOKEN(ANONSUB);
                }
                force_ident_maybe_lex('&');
-               TOKEN(SUB);
+                if (is_sigsub)
+                    TOKEN(SIGSUB);
+                else
+                    TOKEN(SUB);
            }
 
        case KEY_system:
@@ -8837,6 +8974,7 @@ S_pending_ident(pTHX)
 
     DEBUG_T({ PerlIO_printf(Perl_debug_log,
           "### Pending identifier '%s'\n", PL_tokenbuf); });
+    assert(tokenbuf_len >= 2);
 
     /* if we're in a my(), we can't allow dynamics here.
        $foo'bar has already been turned into $foo::bar, so
@@ -8847,6 +8985,8 @@ S_pending_ident(pTHX)
     if (PL_in_my) {
         if (PL_in_my == KEY_our) {     /* "our" is merely analogous to "my" */
             if (has_colon)
+                /* diag_listed_as: No package name allowed for variable %s
+                                   in "our" */
                 yyerror_pv(Perl_form(aTHX_ "No package name allowed for "
                                   "%se %s in \"our\"",
                                   *PL_tokenbuf=='&' ?"subroutin":"variabl",
@@ -8858,13 +8998,13 @@ S_pending_ident(pTHX)
             if (has_colon) {
                 /* "my" variable %s can't be in a package */
                 /* PL_no_myglob is constant */
-                GCC_DIAG_IGNORE(-Wformat-nonliteral);
+                GCC_DIAG_IGNORE_STMT(-Wformat-nonliteral);
                 yyerror_pv(Perl_form(aTHX_ PL_no_myglob,
                             PL_in_my == KEY_my ? "my" : "state",
                             *PL_tokenbuf == '&' ? "subroutin" : "variabl",
                             PL_tokenbuf),
                             UTF ? SVf_UTF8 : 0);
-                GCC_DIAG_RESTORE;
+                GCC_DIAG_RESTORE_STMT;
             }
 
             if (PL_in_my == KEY_sigvar) {
@@ -8910,7 +9050,7 @@ S_pending_ident(pTHX)
                HEK * const stashname = HvNAME_HEK(stash);
                SV *  const sym = newSVhek(stashname);
                 sv_catpvs(sym, "::");
-                sv_catpvn_flags(sym, PL_tokenbuf+1, tokenbuf_len - 1, (UTF ? SV_CATUTF8 : SV_CATBYTES ));
+                sv_catpvn_flags(sym, PL_tokenbuf+1, tokenbuf_len > 0 ? tokenbuf_len - 1 : 0, (UTF ? SV_CATUTF8 : SV_CATBYTES ));
                 pl_yylval.opval = newSVOP(OP_CONST, 0, sym);
                 pl_yylval.opval->op_private = OPpCONST_ENTERED;
                 if (pit != '&')
@@ -8938,7 +9078,7 @@ S_pending_ident(pTHX)
         && PL_lex_state != LEX_NORMAL
         && !PL_lex_brackets)
     {
-        GV *const gv = gv_fetchpvn_flags(PL_tokenbuf + 1, tokenbuf_len - 1,
+        GV *const gv = gv_fetchpvn_flags(PL_tokenbuf + 1, tokenbuf_len > 0 ? tokenbuf_len - 1 : 0,
                                          ( UTF ? SVf_UTF8 : 0 ) | GV_ADDMG,
                                          SVt_PVAV);
         if ((!gv || ((PL_tokenbuf[0] == '@') ? !GvAV(gv) : !GvHV(gv)))
@@ -8955,11 +9095,11 @@ S_pending_ident(pTHX)
     /* build ops for a bareword */
     pl_yylval.opval = newSVOP(OP_CONST, 0,
                                   newSVpvn_flags(PL_tokenbuf + 1,
-                                                     tokenbuf_len - 1,
+                                                      tokenbuf_len > 0 ? tokenbuf_len - 1 : 0,
                                                       UTF ? SVf_UTF8 : 0 ));
     pl_yylval.opval->op_private = OPpCONST_ENTERED;
     if (pit != '&')
-       gv_fetchpvn_flags(PL_tokenbuf+1, tokenbuf_len - 1,
+        gv_fetchpvn_flags(PL_tokenbuf+1, tokenbuf_len > 0 ? tokenbuf_len - 1 : 0,
                     (PL_in_eval ? GV_ADDMULTI : GV_ADD)
                      | ( UTF ? SVf_UTF8 : 0 ),
                     ((PL_tokenbuf[0] == '$') ? SVt_PV
@@ -9176,8 +9316,10 @@ S_new_constant(pTHX_ const char *s, STRLEN len, const char *key, STRLEN keylen,
 
 PERL_STATIC_INLINE void
 S_parse_ident(pTHX_ char **s, char **d, char * const e, int allow_package,
-                    bool is_utf8, bool check_dollar)
+                    bool is_utf8, bool check_dollar, bool tick_warn)
 {
+    int saw_tick = 0;
+    const char *olds = *s;
     PERL_ARGS_ASSERT_PARSE_IDENT;
 
     while (*s < PL_bufend) {
@@ -9211,6 +9353,7 @@ S_parse_ident(pTHX_ char **s, char **d, char * const e, int allow_package,
             *(*d)++ = ':';
             *(*d)++ = ':';
             (*s)++;
+            saw_tick++;
         }
         else if (allow_package && **s == ':' && (*s)[1] == ':'
            /* Disallow things like Foo::$bar. For the curious, this is
@@ -9224,6 +9367,30 @@ S_parse_ident(pTHX_ char **s, char **d, char * const e, int allow_package,
         else
             break;
     }
+    if (UNLIKELY(tick_warn && saw_tick && PL_lex_state == LEX_INTERPNORMAL
+              && !PL_lex_brackets && ckWARN(WARN_SYNTAX))) {
+        char *d;
+       char *d2;
+        Newx(d, *s - olds + saw_tick + 2, char); /* +2 for $# */
+        d2 = d;
+        SAVEFREEPV(d);
+        Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
+                         "Old package separator used in string");
+        if (olds[-1] == '#')
+            *d2++ = olds[-2];
+        *d2++ = olds[-1];
+        while (olds < *s) {
+            if (*olds == '\'') {
+                *d2++ = '\\';
+                *d2++ = *olds++;
+            }
+           else
+                *d2++ = *olds++;
+        }
+        Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
+                         "\t(Did you mean \"%" UTF8f "\" instead?)\n",
+                          UTF8fARG(is_utf8, d2-d, d));
+    }
     return;
 }
 
@@ -9239,7 +9406,7 @@ S_scan_word(pTHX_ char *s, char *dest, STRLEN destlen, int allow_package, STRLEN
 
     PERL_ARGS_ASSERT_SCAN_WORD;
 
-    parse_ident(&s, &d, e, allow_package, is_utf8, TRUE);
+    parse_ident(&s, &d, e, allow_package, is_utf8, TRUE, FALSE);
     *d = '\0';
     *slp = d - dest;
     return s;
@@ -9287,7 +9454,7 @@ S_scan_ident(pTHX_ char *s, char *dest, STRLEN destlen, I32 ck_uni)
        }
     }
     else {  /* See if it is a "normal" identifier */
-        parse_ident(&s, &d, e, 1, is_utf8, FALSE);
+        parse_ident(&s, &d, e, 1, is_utf8, FALSE, TRUE);
     }
     *d = '\0';
     d = dest;
@@ -9306,7 +9473,7 @@ S_scan_ident(pTHX_ char *s, char *dest, STRLEN destlen, I32 ck_uni)
             || isDIGIT_A((U8)s[1])
             || s[1] == '$'
             || s[1] == '{'
-            || strEQs(s+1,"::")) )
+            || memBEGINs(s+1, (STRLEN) (PL_bufend - (s+1)), "::")) )
     {
         /* Dereferencing a value in a scalar variable.
            The alternatives are different syntaxes for a scalar variable.
@@ -9365,7 +9532,7 @@ S_scan_ident(pTHX_ char *s, char *dest, STRLEN destlen, I32 ck_uni)
                    (the later check for } being at the expected point will trap
                    cases where this doesn't pan out.)  */
                 d += is_utf8 ? UTF8SKIP(d) : 1;
-                parse_ident(&s, &d, e, 1, is_utf8, TRUE);
+                parse_ident(&s, &d, e, 1, is_utf8, TRUE, TRUE);
                 *d = '\0';
             }
             else { /* caret word: ${^Foo} ${^CAPTURE[0]} */
@@ -9404,10 +9571,13 @@ S_scan_ident(pTHX_ char *s, char *dest, STRLEN destlen, I32 ck_uni)
 
         if ( !tmp_copline )
             tmp_copline = CopLINE(PL_curcop);
-        if ((skip = s < PL_bufend && isSPACE(*s)))
+        if ((skip = s < PL_bufend && isSPACE(*s))) {
             /* Avoid incrementing line numbers or resetting PL_linestart,
                in case we have to back up.  */
+            STRLEN s_off = s - SvPVX(PL_linestr);
             s2 = peekspace(s);
+            s = SvPVX(PL_linestr) + s_off;
+        }
         else
             s2 = s;
 
@@ -9449,9 +9619,12 @@ S_scan_ident(pTHX_ char *s, char *dest, STRLEN destlen, I32 ck_uni)
             CopLINE_set(PL_curcop, orig_copline);
             PL_parser->herelines = herelines;
            *dest = '\0';
+            PL_parser->sub_no_recover = TRUE;
        }
     }
-    else if (PL_lex_state == LEX_INTERPNORMAL && !PL_lex_brackets && !intuit_more(s))
+    else if (   PL_lex_state == LEX_INTERPNORMAL
+             && !PL_lex_brackets
+             && !intuit_more(s, PL_bufend))
        PL_lex_state = LEX_INTERPEND;
     return s;
 }
@@ -9684,18 +9857,14 @@ S_scan_subst(pTHX_ char *start)
 
        PL_multi_end = 0;
        pm->op_pmflags |= PMf_EVAL;
-       while (es-- > 0) {
-           if (es)
-               sv_catpvs(repl, "eval ");
-           else
-               sv_catpvs(repl, "do ");
-       }
-       sv_catpvs(repl, "{");
+        for (; es > 1; es--) {
+            sv_catpvs(repl, "eval ");
+        }
+        sv_catpvs(repl, "do {");
        sv_catsv(repl, PL_parser->lex_sub_repl);
        sv_catpvs(repl, "}");
        SvREFCNT_dec(PL_parser->lex_sub_repl);
        PL_parser->lex_sub_repl = repl;
-        es = 1;
     }
 
 
@@ -9708,7 +9877,7 @@ S_scan_subst(pTHX_ char *start)
          * the NVX field indicates how many src code lines the replacement
          * spreads over */
         sv_upgrade(PL_parser->lex_sub_repl, SVt_PVNV);
-        ((XPVNV*)SvANY(PL_parser->lex_sub_repl))->xnv_u.xnv_lines = 0;
+        ((XPVNV*)SvANY(PL_parser->lex_sub_repl))->xnv_u.xnv_lines = linediff;
         ((XPVIV*)SvANY(PL_parser->lex_sub_repl))->xiv_u.xivu_eval_seen =
                                                                     cBOOL(es);
     }
@@ -9853,9 +10022,7 @@ S_scan_heredoc(pTHX_ char *s)
        if (! isWORDCHAR_lazy_if_safe(s, PL_bufend, UTF))
            Perl_croak(aTHX_ "Use of bare << to mean <<\"\" is forbidden");
        peek = s;
-        while (
-               isWORDCHAR_lazy_if_safe(peek, PL_bufend, UTF))
-        {
+        while (isWORDCHAR_lazy_if_safe(peek, PL_bufend, UTF)) {
            peek += UTF ? UTF8SKIP(peek) : 1;
        }
        len = (peek - s >= e - d) ? (e - d) : (peek - s);
@@ -9870,7 +10037,7 @@ S_scan_heredoc(pTHX_ char *s)
     len = d - PL_tokenbuf;
 
 #ifndef PERL_STRICT_CR
-    d = strchr(s, '\r');
+    d = (char *) memchr(s, '\r', PL_bufend - s);
     if (d) {
        char * const olds = s;
        s = d;
@@ -9979,8 +10146,9 @@ S_scan_heredoc(pTHX_ char *s)
 
                    /* No whitespace or all! */
                    if (backup == s || *backup == '\n') {
-                       Newxz(indent, indent_len + 1, char);
+                       Newx(indent, indent_len + 1, char);
                        memcpy(indent, backup + 1, indent_len);
+                       indent[indent_len] = 0;
                        s--; /* before our delimiter */
                        PL_parser->herelines--; /* this line doesn't count */
                        break;
@@ -10114,8 +10282,9 @@ S_scan_heredoc(pTHX_ char *s)
 
                /* All whitespace or none! */
                if (backup == found || SPACE_OR_TAB(*backup)) {
-                   Newxz(indent, indent_len + 1, char);
+                   Newx(indent, indent_len + 1, char);
                    memcpy(indent, backup, indent_len);
+                   indent[indent_len] = 0;
                    SvREFCNT_dec(PL_linestr);
                    PL_linestr = linestr_save;
                    PL_linestart = SvPVX(linestr_save);
@@ -10160,7 +10329,7 @@ S_scan_heredoc(pTHX_ char *s)
        while (ss < se) {
            /* newline only? Copy and move on */
            if (*ss == '\n') {
-               sv_catpv(newstr,"\n");
+               sv_catpvs(newstr,"\n");
                ss++;
                linecount++;
 
@@ -10206,7 +10375,7 @@ S_scan_heredoc(pTHX_ char *s)
   interminable:
     SvREFCNT_dec(tmpstr);
     CopLINE_set(PL_curcop, origline);
-    missingterm(PL_tokenbuf + 1);
+    missingterm(PL_tokenbuf + 1, sizeof(PL_tokenbuf) - 1);
 }
 
 /* scan_inputsymbol
@@ -10239,7 +10408,7 @@ S_scan_inputsymbol(pTHX_ char *start)
 
     PERL_ARGS_ASSERT_SCAN_INPUTSYMBOL;
 
-    end = strchr(s, '\n');
+    end = (char *) memchr(s, '\n', PL_bufend - s);
     if (!end)
        end = PL_bufend;
     if (s[1] == '<' && s[2] == '>' && s[3] == '>') {
@@ -10434,7 +10603,7 @@ S_scan_str(pTHX_ char *start, int keep_bracketed_quoted, int keep_delims, int re
     I32 brackets = 1;          /* bracket nesting level */
     bool has_utf8 = FALSE;     /* is there any utf8 content? */
     IV termcode;               /* terminating char. code */
-    U8 termstr[UTF8_MAXBYTES]; /* terminating string */
+    U8 termstr[UTF8_MAXBYTES+1]; /* terminating string */
     STRLEN termlen;            /* length of terminating string */
     line_t herelines;
 
@@ -10442,14 +10611,11 @@ S_scan_str(pTHX_ char *start, int keep_bracketed_quoted, int keep_delims, int re
     const char * opening_delims = "([{<";
     const char * closing_delims = ")]}>";
 
+    /* The only non-UTF character that isn't a stand alone grapheme is
+     * white-space, hence can't be a delimiter. */
     const char * non_grapheme_msg = "Use of unassigned code point or"
                                     " non-standalone grapheme for a delimiter"
-                                    " will be a fatal error starting in Perl"
-                                    " 5.30";
-    /* The only non-UTF character that isn't a stand alone grapheme is
-     * white-space, hence can't be a delimiter.  So can skip for non-UTF-8 */
-    bool check_grapheme = UTF && ckWARN_d(WARN_DEPRECATED);
-
+                                    " is not allowed";
     PERL_ARGS_ASSERT_SCAN_STR;
 
     /* skip space before the delimiter */
@@ -10468,26 +10634,12 @@ S_scan_str(pTHX_ char *start, int keep_bracketed_quoted, int keep_delims, int re
     }
     else {
        termcode = utf8_to_uvchr_buf((U8*)s, (U8*)PL_bufend, &termlen);
-        if (check_grapheme) {
-            if (   UNLIKELY(UNICODE_IS_SUPER(termcode))
-                || UNLIKELY(UNICODE_IS_NONCHAR(termcode)))
-            {
-                /* These are considered graphemes, and since the ending
-                 * delimiter will be the same, we don't have to check the other
-                 * end */
-                check_grapheme = FALSE;
-            }
-            else if (UNLIKELY(! _is_grapheme((U8 *) start,
-                                             (U8 *) s,
-                                             (U8 *) PL_bufend,
-                                             termcode)))
-            {
-                Perl_warner(aTHX_ packWARN(WARN_DEPRECATED), "%s", non_grapheme_msg);
-
-                /* Don't have to check the other end, as have already warned at
-                 * this one */
-                check_grapheme = FALSE;
-            }
+        if (UTF && UNLIKELY(! _is_grapheme((U8 *) start,
+                                           (U8 *) s,
+                                           (U8 *) PL_bufend,
+                                                  termcode)))
+        {
+            yyerror(non_grapheme_msg);
         }
 
        Copy(s, termstr, termlen, U8);
@@ -10553,14 +10705,13 @@ S_scan_str(pTHX_ char *start, int keep_bracketed_quoted, int keep_delims, int re
                     if (   s + termlen <= PL_bufend
                         && memEQ(s + 1, (char*)termstr + 1, termlen - 1))
                     {
-                        if (   check_grapheme
+                        if (   UTF
                             && UNLIKELY(! _is_grapheme((U8 *) start,
-                                                              (U8 *) s,
-                                                              (U8 *) PL_bufend,
+                                                       (U8 *) s,
+                                                       (U8 *) PL_bufend,
                                                               termcode)))
                         {
-                            Perl_warner(aTHX_ packWARN(WARN_DEPRECATED),
-                                        "%s", non_grapheme_msg);
+                            yyerror(non_grapheme_msg);
                         }
                        break;
                     }
@@ -10861,6 +11012,7 @@ Perl_scan_num(pTHX_ const char *start, YYSTYPE* lvalp)
                  digit:
                    just_zero = FALSE;
                    if (!overflowed) {
+                       assert(shift >= 0);
                        x = u << shift; /* make room for the digit */
 
                         total_bits += shift;
@@ -10941,19 +11093,22 @@ Perl_scan_num(pTHX_ const char *start, YYSTYPE* lvalp)
                     NV nv_mult = 1.0;
 #endif
                     bool accumulate = TRUE;
-                    for (h++; (isXDIGIT(*h) || *h == '_'); h++) {
+                    U8 b;
+                    int lim = 1 << shift;
+                    for (h++; ((isXDIGIT(*h) && (b = XDIGIT_VALUE(*h)) < lim) ||
+                               *h == '_'); h++) {
                         if (isXDIGIT(*h)) {
-                            U8 b = XDIGIT_VALUE(*h);
                             significant_bits += shift;
 #ifdef HEXFP_UQUAD
                             if (accumulate) {
                                 if (significant_bits < NV_MANT_DIG) {
                                     /* We are in the long "run" of xdigits,
                                      * accumulate the full four bits. */
+                                   assert(shift >= 0);
                                     hexfp_uquad <<= shift;
                                     hexfp_uquad |= b;
                                     hexfp_frac_bits += shift;
-                                } else {
+                                } else if (significant_bits - shift < NV_MANT_DIG) {
                                     /* We are at a hexdigit either at,
                                      * or straddling, the edge of mantissa.
                                      * We will try grabbing as many as
@@ -10962,7 +11117,9 @@ Perl_scan_num(pTHX_ const char *start, YYSTYPE* lvalp)
                                       significant_bits - NV_MANT_DIG;
                                     if (tail <= 0)
                                        tail += shift;
+                                   assert(tail >= 0);
                                     hexfp_uquad <<= tail;
+                                   assert((shift - tail) >= 0);
                                     hexfp_uquad |= b >> (shift - tail);
                                     hexfp_frac_bits += tail;
 
@@ -11001,7 +11158,7 @@ Perl_scan_num(pTHX_ const char *start, YYSTYPE* lvalp)
                             }
 #else /* HEXFP_NV */
                             if (accumulate) {
-                                nv_mult /= 16.0;
+                                nv_mult /= nvshift[shift];
                                 if (nv_mult > 0.0)
                                     hexfp_nv += b * nv_mult;
                                 else
@@ -11270,7 +11427,6 @@ Perl_scan_num(pTHX_ const char *start, YYSTYPE* lvalp)
               floatit = TRUE;
         }
        if (floatit) {
-            STORE_LC_NUMERIC_UNDERLYING_SET_STANDARD();
            /* terminate the string */
            *d = '\0';
             if (UNLIKELY(hexfp)) {
@@ -11287,7 +11443,6 @@ Perl_scan_num(pTHX_ const char *start, YYSTYPE* lvalp)
             } else {
                 nv = Atof(PL_tokenbuf);
             }
-            RESTORE_LC_NUMERIC_UNDERLYING();
             sv = newSVnv(nv);
        }
 
@@ -11386,7 +11541,7 @@ S_scan_formline(pTHX_ char *s)
            if (!got_some)
                break;
        }
-       incline(s);
+       incline(s, PL_bufend);
     }
   enough:
     if (!SvCUR(stuff) || needargs)
@@ -11443,6 +11598,39 @@ Perl_start_subparse(pTHX_ I32 is_format, U32 flags)
     return oldsavestack_ix;
 }
 
+
+/* Do extra initialisation of a CV (typically one just created by
+ * start_subparse()) if that CV is for a named sub
+ */
+
+void
+Perl_init_named_cv(pTHX_ CV *cv, OP *nameop)
+{
+    PERL_ARGS_ASSERT_INIT_NAMED_CV;
+
+    if (nameop->op_type == OP_CONST) {
+        const char *const name = SvPV_nolen_const(((SVOP*)nameop)->op_sv);
+        if (   strEQ(name, "BEGIN")
+            || strEQ(name, "END")
+            || strEQ(name, "INIT")
+            || strEQ(name, "CHECK")
+            || strEQ(name, "UNITCHECK")
+        )
+          CvSPECIAL_on(cv);
+    }
+    else
+    /* State subs inside anonymous subs need to be
+     clonable themselves. */
+    if (   CvANON(CvOUTSIDE(cv))
+        || CvCLONE(CvOUTSIDE(cv))
+        || !PadnameIsSTATE(PadlistNAMESARRAY(CvPADLIST(
+                        CvOUTSIDE(cv)
+                     ))[nameop->op_targ])
+    )
+      CvCLONE_on(cv);
+}
+
+
 static int
 S_yywarn(pTHX_ const char *const s, U32 flags)
 {
@@ -11634,7 +11822,9 @@ S_swallow_bom(pTHX_ U8 *s)
                /* diag_listed_as: Unsupported script encoding %s */
                Perl_croak(aTHX_ "Unsupported script encoding UTF-32LE");
 #ifndef PERL_NO_UTF16_FILTER
+#ifdef DEBUGGING
            if (DEBUG_p_TEST || DEBUG_T_TEST) PerlIO_printf(Perl_debug_log, "UTF-16LE script encoding (BOM)\n");
+#endif
            s += 2;
            if (PL_bufend > (char*)s) {
                s = add_utf16_textfilter(s, TRUE);
@@ -11648,7 +11838,9 @@ S_swallow_bom(pTHX_ U8 *s)
     case 0xFE:
        if (s[1] == 0xFF) {   /* UTF-16 big-endian? */
 #ifndef PERL_NO_UTF16_FILTER
+#ifdef DEBUGGING
            if (DEBUG_p_TEST || DEBUG_T_TEST) PerlIO_printf(Perl_debug_log, "UTF-16BE script encoding (BOM)\n");
+#endif
            s += 2;
            if (PL_bufend > (char *)s) {
                s = add_utf16_textfilter(s, FALSE);
@@ -11660,10 +11852,11 @@ S_swallow_bom(pTHX_ U8 *s)
        }
        break;
     case BOM_UTF8_FIRST_BYTE: {
-        const STRLEN len = sizeof(BOM_UTF8_TAIL) - 1; /* Exclude trailing NUL */
-        if (slen > len && memEQ(s+1, BOM_UTF8_TAIL, len)) {
+        if (memBEGINs(s+1, slen - 1, BOM_UTF8_TAIL)) {
+#ifdef DEBUGGING
             if (DEBUG_p_TEST || DEBUG_T_TEST) PerlIO_printf(Perl_debug_log, "UTF-8 script encoding (BOM)\n");
-            s += len + 1;                      /* UTF-8 */
+#endif
+            s += sizeof(BOM_UTF8) - 1;                     /* UTF-8 */
         }
         break;
     }
@@ -11681,7 +11874,9 @@ S_swallow_bom(pTHX_ U8 *s)
                   * 00 xx 00 xx
                   * are a good indicator of UTF-16BE. */
 #ifndef PERL_NO_UTF16_FILTER
+#ifdef DEBUGGING
                  if (DEBUG_p_TEST || DEBUG_T_TEST) PerlIO_printf(Perl_debug_log, "UTF-16BE script encoding (no BOM)\n");
+#endif
                  s = add_utf16_textfilter(s, FALSE);
 #else
                  /* diag_listed_as: Unsupported script encoding %s */
@@ -11697,7 +11892,9 @@ S_swallow_bom(pTHX_ U8 *s)
                   * xx 00 xx 00
                   * are a good indicator of UTF-16LE. */
 #ifndef PERL_NO_UTF16_FILTER
+#ifdef DEBUGGING
              if (DEBUG_p_TEST || DEBUG_T_TEST) PerlIO_printf(Perl_debug_log, "UTF-16LE script encoding (no BOM)\n");
+#endif
              s = add_utf16_textfilter(s, TRUE);
 #else
              /* diag_listed_as: Unsupported script encoding %s */
@@ -11798,9 +11995,14 @@ S_utf16_textfilter(pTHX_ int idx, SV *sv, int maxlen)
            }
        }
 
+        /* 'chars' isn't quite the right name, as code points above 0xFFFF
+         * require 4 bytes per char */
        chars = SvCUR(utf16_buffer) >> 1;
        have = SvCUR(utf8_buffer);
-       SvGROW(utf8_buffer, have + chars * 3 + 1);
+
+        /* Assume the worst case size as noted by the functions: twice the
+         * number of input bytes */
+       SvGROW(utf8_buffer, have + chars * 4 + 1);
 
        if (reverse) {
            end = utf16_to_utf8_reversed((U8*)SvPVX(utf16_buffer),
@@ -11959,6 +12161,79 @@ Perl_keyword_plugin_standard(pTHX_
     return KEYWORD_PLUGIN_DECLINE;
 }
 
+/*
+=for apidoc Amx|void|wrap_keyword_plugin|Perl_keyword_plugin_t new_plugin|Perl_keyword_plugin_t *old_plugin_p
+
+Puts a C function into the chain of keyword plugins.  This is the
+preferred way to manipulate the L</PL_keyword_plugin> variable.
+C<new_plugin> is a pointer to the C function that is to be added to the
+keyword plugin chain, and C<old_plugin_p> points to the storage location
+where a pointer to the next function in the chain will be stored.  The
+value of C<new_plugin> is written into the L</PL_keyword_plugin> variable,
+while the value previously stored there is written to C<*old_plugin_p>.
+
+L</PL_keyword_plugin> is global to an entire process, and a module wishing
+to hook keyword parsing may find itself invoked more than once per
+process, typically in different threads.  To handle that situation, this
+function is idempotent.  The location C<*old_plugin_p> must initially
+(once per process) contain a null pointer.  A C variable of static
+duration (declared at file scope, typically also marked C<static> to give
+it internal linkage) will be implicitly initialised appropriately, if it
+does not have an explicit initialiser.  This function will only actually
+modify the plugin chain if it finds C<*old_plugin_p> to be null.  This
+function is also thread safe on the small scale.  It uses appropriate
+locking to avoid race conditions in accessing L</PL_keyword_plugin>.
+
+When this function is called, the function referenced by C<new_plugin>
+must be ready to be called, except for C<*old_plugin_p> being unfilled.
+In a threading situation, C<new_plugin> may be called immediately, even
+before this function has returned.  C<*old_plugin_p> will always be
+appropriately set before C<new_plugin> is called.  If C<new_plugin>
+decides not to do anything special with the identifier that it is given
+(which is the usual case for most calls to a keyword plugin), it must
+chain the plugin function referenced by C<*old_plugin_p>.
+
+Taken all together, XS code to install a keyword plugin should typically
+look something like this:
+
+    static Perl_keyword_plugin_t next_keyword_plugin;
+    static OP *my_keyword_plugin(pTHX_
+        char *keyword_plugin, STRLEN keyword_len, OP **op_ptr)
+    {
+        if (memEQs(keyword_ptr, keyword_len,
+                   "my_new_keyword")) {
+            ...
+        } else {
+            return next_keyword_plugin(aTHX_
+                keyword_ptr, keyword_len, op_ptr);
+        }
+    }
+    BOOT:
+        wrap_keyword_plugin(my_keyword_plugin,
+                            &next_keyword_plugin);
+
+Direct access to L</PL_keyword_plugin> should be avoided.
+
+=cut
+*/
+
+void
+Perl_wrap_keyword_plugin(pTHX_
+    Perl_keyword_plugin_t new_plugin, Perl_keyword_plugin_t *old_plugin_p)
+{
+    dVAR;
+
+    PERL_UNUSED_CONTEXT;
+    PERL_ARGS_ASSERT_WRAP_KEYWORD_PLUGIN;
+    if (*old_plugin_p) return;
+    KEYWORD_PLUGIN_MUTEX_LOCK;
+    if (!*old_plugin_p) {
+        *old_plugin_p = PL_keyword_plugin;
+        PL_keyword_plugin = new_plugin;
+    }
+    KEYWORD_PLUGIN_MUTEX_UNLOCK;
+}
+
 #define parse_recdescent(g,p) S_parse_recdescent(aTHX_ g,p)
 static void
 S_parse_recdescent(pTHX_ int gramtype, I32 fakeeof)