X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/da51bb9b4f7f527464b5e38aca8bcb956de1bbbc..584420f022db5722:/toke.c

diff --git a/toke.c b/toke.c
index 25c3f3e..a375a77 100644
--- a/toke.c
+++ b/toke.c
@@ -49,6 +49,25 @@
 #define PL_pending_ident        (PL_parser->pending_ident)
 #define PL_preambled		(PL_parser->preambled)
 #define PL_sublex_info		(PL_parser->sublex_info)
+#define PL_linestr		(PL_parser->linestr)
+#define PL_expect		(PL_parser->expect)
+#define PL_copline		(PL_parser->copline)
+#define PL_bufptr		(PL_parser->bufptr)
+#define PL_oldbufptr		(PL_parser->oldbufptr)
+#define PL_oldoldbufptr		(PL_parser->oldoldbufptr)
+#define PL_linestart		(PL_parser->linestart)
+#define PL_bufend		(PL_parser->bufend)
+#define PL_last_uni		(PL_parser->last_uni)
+#define PL_last_lop		(PL_parser->last_lop)
+#define PL_last_lop_op		(PL_parser->last_lop_op)
+#define PL_lex_state		(PL_parser->lex_state)
+#define PL_rsfp			(PL_parser->rsfp)
+#define PL_rsfp_filters		(PL_parser->rsfp_filters)
+#define PL_in_my		(PL_parser->in_my)
+#define PL_in_my_stash		(PL_parser->in_my_stash)
+#define PL_tokenbuf		(PL_parser->tokenbuf)
+#define PL_multi_end		(PL_parser->multi_end)
+#define PL_error_count		(PL_parser->error_count)
 
 #ifdef PERL_MAD
 #  define PL_endwhite		(PL_parser->endwhite)
@@ -63,6 +82,13 @@
 #  define PL_thisstuff		(PL_parser->thisstuff)
 #  define PL_thistoken		(PL_parser->thistoken)
 #  define PL_thiswhite		(PL_parser->thiswhite)
+#  define PL_thiswhite		(PL_parser->thiswhite)
+#  define PL_nexttoke		(PL_parser->nexttoke)
+#  define PL_curforce		(PL_parser->curforce)
+#else
+#  define PL_nexttoke		(PL_parser->nexttoke)
+#  define PL_nexttype		(PL_parser->nexttype)
+#  define PL_nextval		(PL_parser->nextval)
 #endif
 
 static int
@@ -71,7 +97,6 @@ S_pending_ident(pTHX);
 static const char ident_too_long[] = "Identifier too long";
 static const char commaless_variable_list[] = "comma-less variable list";
 
-static void restore_rsfp(pTHX_ void *f);
 #ifndef PERL_NO_UTF16_FILTER
 static I32 utf16_textfilter(pTHX_ int idx, SV *sv, int maxlen);
 static I32 utf16rev_textfilter(pTHX_ int idx, SV *sv, int maxlen);
@@ -615,22 +640,30 @@ S_cr_textfilter(pTHX_ int idx, SV *sv, int maxlen)
 
 /*
  * Perl_lex_start
- * Initialize variables.  Uses the Perl save_stack to save its state (for
- * recursive calls to the parser).
+ *
+ * Create a parser object and initialise its parser and lexer fields
+ *
+ * rsfp       is the opened file handle to read from (if any),
+ *
+ * line       holds any initial content already read from the file (or in
+ *            the case of no file, such as an eval, the whole contents);
+ *
+ * new_filter indicates that this is a new file and it shouldn't inherit
+ *            the filters from the current parser (ie require).
  */
 
 void
-Perl_lex_start(pTHX_ SV *line)
+Perl_lex_start(pTHX_ SV *line, PerlIO *rsfp, bool new_filter)
 {
     dVAR;
     const char *s = NULL;
     STRLEN len;
-    yy_parser *parser;
+    yy_parser *parser, *oparser;
 
     /* create and initialise a parser */
 
     Newxz(parser, 1, yy_parser);
-    parser->old_parser = PL_parser;
+    parser->old_parser = oparser = PL_parser;
     PL_parser = parser;
 
     Newx(parser->stack, YYINITDEPTH, yy_stack_frame);
@@ -641,76 +674,77 @@ Perl_lex_start(pTHX_ SV *line)
     parser->yyerrstatus = 0;
     parser->yychar = YYEMPTY;		/* Cause a token to be read.  */
 
+    /* on scope exit, free this parser and restore any outer one */
+    SAVEPARSER(parser);
+    parser->saved_curcop = PL_curcop;
+
     /* initialise lexer state */
 
-    SAVEI32(PL_lex_state);
 #ifdef PERL_MAD
-    if (PL_lex_state == LEX_KNOWNEXT) {
-	I32 toke = parser->old_parser->lasttoke;
- 	while (--toke >= 0) {
-	    SAVEI32(PL_nexttoke[toke].next_type);
-	    SAVEVPTR(PL_nexttoke[toke].next_val);
-	    if (PL_madskills)
-		SAVEVPTR(PL_nexttoke[toke].next_mad);
-	}
-    }
-    SAVEI32(PL_curforce);
+    parser->curforce = -1;
 #else
-    if (PL_lex_state == LEX_KNOWNEXT) {
-	I32 toke = PL_nexttoke;
-	while (--toke >= 0) {
-	    SAVEI32(PL_nexttype[toke]);
-	    SAVEVPTR(PL_nextval[toke]);
-	}
-	SAVEI32(PL_nexttoke);
-    }
+    parser->nexttoke = 0;
 #endif
-    SAVECOPLINE(PL_curcop);
-    SAVEPPTR(PL_bufptr);
-    SAVEPPTR(PL_bufend);
-    SAVEPPTR(PL_oldbufptr);
-    SAVEPPTR(PL_oldoldbufptr);
-    SAVEPPTR(PL_last_lop);
-    SAVEPPTR(PL_last_uni);
-    SAVEPPTR(PL_linestart);
-    SAVESPTR(PL_linestr);
-    SAVEDESTRUCTOR_X(restore_rsfp, PL_rsfp);
-    SAVEINT(PL_expect);
+    parser->copline = NOLINE;
+    parser->lex_state = LEX_NORMAL;
+    parser->expect = XSTATE;
+    parser->rsfp = rsfp;
+    parser->rsfp_filters = (new_filter || !oparser) ? newAV()
+		: (AV*)SvREFCNT_inc(oparser->rsfp_filters);
 
-    PL_lex_state = LEX_NORMAL;
-    PL_expect = XSTATE;
     Newx(parser->lex_brackstack, 120, char);
     Newx(parser->lex_casestack, 12, char);
     *parser->lex_casestack = '\0';
-#ifndef PERL_MAD
-    PL_nexttoke = 0;
-#endif
 
     if (line) {
 	s = SvPV_const(line, len);
     } else {
 	len = 0;
     }
+
     if (!len) {
-	PL_linestr = newSVpvs("\n;");
+	parser->linestr = newSVpvs("\n;");
     } else if (SvREADONLY(line) || s[len-1] != ';') {
-	PL_linestr = newSVsv(line);
+	parser->linestr = newSVsv(line);
 	if (s[len-1] != ';')
-	    sv_catpvs(PL_linestr, "\n;");
+	    sv_catpvs(parser->linestr, "\n;");
     } else {
 	SvTEMP_off(line);
 	SvREFCNT_inc_simple_void_NN(line);
-	PL_linestr = line;
-    }
-    /* PL_linestr needs to survive until end of scope, not just the next
-       FREETMPS. See changes 17505 and 17546 which fixed the symptoms only.  */
-    SAVEFREESV(PL_linestr);
-    PL_oldoldbufptr = PL_oldbufptr = PL_bufptr = PL_linestart = SvPVX(PL_linestr);
-    PL_bufend = PL_bufptr + SvCUR(PL_linestr);
-    PL_last_lop = PL_last_uni = NULL;
-    PL_rsfp = 0;
+	parser->linestr = line;
+    }
+    parser->oldoldbufptr =
+	parser->oldbufptr =
+	parser->bufptr =
+	parser->linestart = SvPVX(parser->linestr);
+    parser->bufend = parser->bufptr + SvCUR(parser->linestr);
+    parser->last_lop = parser->last_uni = NULL;
+}
+
+
+/* delete a parser object */
+
+void
+Perl_parser_free(pTHX_  const yy_parser *parser)
+{
+    PL_curcop = parser->saved_curcop;
+    SvREFCNT_dec(parser->linestr);
+
+    if (parser->rsfp == PerlIO_stdin())
+	PerlIO_clearerr(parser->rsfp);
+    else if (parser->rsfp && parser->old_parser
+			  && parser->rsfp != parser->old_parser->rsfp)
+	PerlIO_close(parser->rsfp);
+    SvREFCNT_dec(parser->rsfp_filters);
+
+    Safefree(parser->stack);
+    Safefree(parser->lex_brackstack);
+    Safefree(parser->lex_casestack);
+    PL_parser = parser->old_parser;
+    Safefree(parser);
 }
 
+
 /*
  * Perl_lex_end
  * Finalizer for lexing operations.  Must be called when the parser is
@@ -735,13 +769,12 @@ Perl_lex_end(pTHX)
  */
 
 STATIC void
-S_incline(pTHX_ char *s)
+S_incline(pTHX_ const char *s)
 {
     dVAR;
-    char *t;
-    char *n;
-    char *e;
-    char ch;
+    const char *t;
+    const char *n;
+    const char *e;
 
     CopLINE_inc(PL_curcop);
     if (*s++ != '#')
@@ -781,34 +814,48 @@ S_incline(pTHX_ char *s)
     if (*e != '\n' && *e != '\0')
 	return;		/* false alarm */
 
-    ch = *t;
-    *t = '\0';
     if (t - s > 0) {
+	const STRLEN len = t - s;
 #ifndef USE_ITHREADS
 	const char * const cf = CopFILE(PL_curcop);
 	STRLEN tmplen = cf ? strlen(cf) : 0;
 	if (tmplen > 7 && strnEQ(cf, "(eval ", 6)) {
 	    /* must copy *{"::_<(eval N)[oldfilename:L]"}
 	     * to *{"::_<newfilename"} */
-	    char smallbuf[256], smallbuf2[256];
-	    char *tmpbuf, *tmpbuf2;
-	    GV **gvp, *gv2;
-	    STRLEN tmplen2 = strlen(s);
-	    if (tmplen + 3 < sizeof smallbuf)
+	    /* However, the long form of evals is only turned on by the
+	       debugger - usually they're "(eval %lu)" */
+	    char smallbuf[128];
+	    char *tmpbuf;
+	    GV **gvp;
+	    STRLEN tmplen2 = len;
+	    if (tmplen + 2 <= sizeof smallbuf)
 		tmpbuf = smallbuf;
 	    else
-		Newx(tmpbuf, tmplen + 3, char);
-	    if (tmplen2 + 3 < sizeof smallbuf2)
-		tmpbuf2 = smallbuf2;
-	    else
-		Newx(tmpbuf2, tmplen2 + 3, char);
-	    tmpbuf[0] = tmpbuf2[0] = '_';
-	    tmpbuf[1] = tmpbuf2[1] = '<';
-	    memcpy(tmpbuf + 2, cf, ++tmplen);
-	    memcpy(tmpbuf2 + 2, s, ++tmplen2);
-	    ++tmplen; ++tmplen2;
+		Newx(tmpbuf, tmplen + 2, char);
+	    tmpbuf[0] = '_';
+	    tmpbuf[1] = '<';
+	    memcpy(tmpbuf + 2, cf, tmplen);
+	    tmplen += 2;
 	    gvp = (GV**)hv_fetch(PL_defstash, tmpbuf, tmplen, FALSE);
 	    if (gvp) {
+		char *tmpbuf2;
+		GV *gv2;
+
+		if (tmplen2 + 2 <= sizeof smallbuf)
+		    tmpbuf2 = smallbuf;
+		else
+		    Newx(tmpbuf2, tmplen2 + 2, char);
+
+		if (tmpbuf2 != smallbuf || tmpbuf != smallbuf) {
+		    /* Either they malloc'd it, or we malloc'd it,
+		       so no prefix is present in ours.  */
+		    tmpbuf2[0] = '_';
+		    tmpbuf2[1] = '<';
+		}
+
+		memcpy(tmpbuf2 + 2, s, tmplen2);
+		tmplen2 += 2;
+
 		gv2 = *(GV**)hv_fetch(PL_defstash, tmpbuf2, tmplen2, TRUE);
 		if (!isGV(gv2)) {
 		    gv_init(gv2, PL_defstash, tmpbuf2, tmplen2, FALSE);
@@ -817,15 +864,15 @@ S_incline(pTHX_ char *s)
 		    GvHV(gv2) = (HV*)SvREFCNT_inc(GvHV(*gvp));
 		    GvAV(gv2) = (AV*)SvREFCNT_inc(GvAV(*gvp));
 		}
+
+		if (tmpbuf2 != smallbuf) Safefree(tmpbuf2);
 	    }
 	    if (tmpbuf != smallbuf) Safefree(tmpbuf);
-	    if (tmpbuf2 != smallbuf2) Safefree(tmpbuf2);
 	}
 #endif
 	CopFILE_free(PL_curcop);
-	CopFILE_set(PL_curcop, s);
+	CopFILE_setn(PL_curcop, s, len);
     }
-    *t = ch;
     CopLINE_set(PL_curcop, atoi(n)-1);
 }
 
@@ -910,8 +957,7 @@ S_update_debugger_info(pTHX_ SV *orig_sv, const char *buf, STRLEN len)
 {
     AV *av = CopFILEAVx(PL_curcop);
     if (av) {
-	SV * const sv = newSV(0);
-	sv_upgrade(sv, SVt_PVMG);
+	SV * const sv = newSV_type(SVt_PVMG);
 	if (orig_sv)
 	    sv_setsv(sv, orig_sv);
 	else
@@ -1013,10 +1059,10 @@ S_skipspace(pTHX_ register char *s)
 	    /* XXX these shouldn't really be added here, can't set PL_faketokens */
 	    if (PL_minus_p) {
 #ifdef PERL_MAD
-		sv_catpv(PL_linestr,
+		sv_catpvs(PL_linestr,
 			 ";}continue{print or die qq(-p destination: $!\\n);}");
 #else
-		sv_setpv(PL_linestr,
+		sv_setpvs(PL_linestr,
 			 ";}continue{print or die qq(-p destination: $!\\n);}");
 #endif
 		PL_minus_n = PL_minus_p = 0;
@@ -1236,7 +1282,7 @@ S_curmad(pTHX_ char slot, SV *sv)
     /* keep a slot open for the head of the list? */
     if (slot != '_' && *where && (*where)->mad_key == '^') {
 	(*where)->mad_key = slot;
-	sv_free((*where)->mad_val);
+	sv_free((SV*)((*where)->mad_val));
 	(*where)->mad_val = (void*)sv;
     }
     else
@@ -1334,6 +1380,8 @@ S_force_word(pTHX_ register char *start, int token, int check_keyword, int allow
 		PL_expect = XOPERATOR;
 	    }
 	}
+	if (PL_madskills)
+	    curmad('g', newSVpvs( "forced" ));
 	NEXTVAL_NEXTTOKE.opval
 	    = (OP*)newSVOP(OP_CONST,0,
 			   S_newSV_maybe_utf8(aTHX_ PL_tokenbuf, len));
@@ -1597,7 +1645,7 @@ S_sublex_start(pTHX)
     }
 
     PL_sublex_info.super_state = PL_lex_state;
-    PL_sublex_info.sub_inwhat = op_type;
+    PL_sublex_info.sub_inwhat = (U16)op_type;
     PL_sublex_info.sub_op = PL_lex_op;
     PL_lex_state = LEX_INTERPPUSH;
 
@@ -1626,13 +1674,13 @@ S_sublex_push(pTHX)
     ENTER;
 
     PL_lex_state = PL_sublex_info.super_state;
-    SAVEI32(PL_lex_dojoin);
+    SAVEBOOL(PL_lex_dojoin);
     SAVEI32(PL_lex_brackets);
     SAVEI32(PL_lex_casemods);
     SAVEI32(PL_lex_starts);
-    SAVEI32(PL_lex_state);
+    SAVEI8(PL_lex_state);
     SAVEVPTR(PL_lex_inpat);
-    SAVEI32(PL_lex_inwhat);
+    SAVEI16(PL_lex_inwhat);
     SAVECOPLINE(PL_curcop);
     SAVEPPTR(PL_bufptr);
     SAVEPPTR(PL_bufend);
@@ -2011,7 +2059,7 @@ S_scan_const(pTHX_ char *start)
 		    *d++ = NATIVE_TO_NEED(has_utf8,*s++);
 	    }
 	    else if (s[2] == '{' /* This should match regcomp.c */
-		     || ((s[2] == 'p' || s[2] == '?') && s[3] == '{'))
+		    || (s[2] == '?' && s[3] == '{'))
 	    {
 		I32 count = 1;
 		char *regparse = s + (s[2] == '{' ? 3 : 4);
@@ -2633,7 +2681,8 @@ S_intuit_method(pTHX_ char *start, GV *gv, CV *cv)
      */
 
     if (*start == '$') {
-	if (gv || PL_last_lop_op == OP_PRINT || isUPPER(*PL_tokenbuf))
+	if (gv || PL_last_lop_op == OP_PRINT || PL_last_lop_op == OP_SAY ||
+		isUPPER(*PL_tokenbuf))
 	    return 0;
 #ifdef PERL_MAD
 	len = start - SvPVX(PL_linestr);
@@ -2732,6 +2781,9 @@ Perl_filter_add(pTHX_ filter_t funcp, SV *datasv)
     if (!funcp)
 	return NULL;
 
+    if (!PL_parser)
+	return NULL;
+
     if (!PL_rsfp_filters)
 	PL_rsfp_filters = newAV();
     if (!datasv)
@@ -2759,7 +2811,7 @@ Perl_filter_del(pTHX_ filter_t funcp)
     DEBUG_P(PerlIO_printf(Perl_debug_log, "filter_del func %p",
 			  FPTR2DPTR(void*, funcp)));
 #endif
-    if (!PL_rsfp_filters || AvFILLp(PL_rsfp_filters)<0)
+    if (!PL_parser || !PL_rsfp_filters || AvFILLp(PL_rsfp_filters)<0)
 	return;
     /* if filter is on top of stack (usual case) just pop it off */
     datasv = FILTER_DATA(AvFILLp(PL_rsfp_filters));
@@ -2795,7 +2847,7 @@ Perl_filter_read(pTHX_ int idx, SV *buf_sv, int maxlen)
 #endif
 	: maxlen;
 
-    if (!PL_rsfp_filters)
+    if (!PL_parser || !PL_rsfp_filters)
 	return -1;
     if (idx > AvFILLp(PL_rsfp_filters)) {       /* Any more filters?	*/
 	/* Provide a default input filter to make life easy.	*/
@@ -2909,7 +2961,7 @@ S_readpipe_override(pTHX)
 		&& GvCVu(gv_readpipe) && GvIMPORTED_CV(gv_readpipe))
 	    ||
 	    ((gvp = (GV**)hv_fetchs(PL_globalstash, "readpipe", FALSE))
-	     && (gv_readpipe = *gvp) != (GV*)&PL_sv_undef
+	     && (gv_readpipe = *gvp) && isGV_with_GP(gv_readpipe)
 	     && GvCVu(gv_readpipe) && GvIMPORTED_CV(gv_readpipe)))
     {
 	PL_lex_op = (OP*)newUNOP(OP_ENTERSUB, OPf_STACKED,
@@ -3893,10 +3945,11 @@ Perl_yylex(pTHX)
 #endif
 #ifdef PERL_MAD
 	PL_realtokenstart = -1;
-	s = SKIPSPACE0(s);
-#else
-	s++;
+	if (!PL_thiswhite)
+	    PL_thiswhite = newSVpvs("");
+	sv_catpvn(PL_thiswhite, s, 1);
 #endif
+	s++;
 	goto retry;
     case '#':
     case '\n':
@@ -4119,7 +4172,8 @@ Perl_yylex(pTHX)
 	    Mop(OP_MODULO);
 	}
 	PL_tokenbuf[0] = '%';
-	s = scan_ident(s, PL_bufend, PL_tokenbuf + 1, sizeof PL_tokenbuf - 1, TRUE);
+	s = scan_ident(s, PL_bufend, PL_tokenbuf + 1,
+		sizeof PL_tokenbuf - 1, FALSE);
 	if (!PL_tokenbuf[1]) {
 	    PREREF('%');
 	}
@@ -4242,10 +4296,6 @@ Perl_yylex(pTHX)
 			sv_free(sv);
 			CvMETHOD_on(PL_compcv);
 		    }
-		    else if (!PL_in_my && len == 9 && strnEQ(SvPVX(sv), "assertion", len)) {
-			sv_free(sv);
-		        CvASSERTION_on(PL_compcv);
-		    }
 		    /* After we've set the flags, it could be argued that
 		       we don't need to do the attributes.pm-based setting
 		       process, and shouldn't bother appending recognized
@@ -5152,7 +5202,7 @@ Perl_yylex(pTHX)
 		}
 		if (!ogv &&
 		    (gvp = (GV**)hv_fetch(PL_globalstash,PL_tokenbuf,len,FALSE)) &&
-		    (gv = *gvp) != (GV*)&PL_sv_undef &&
+		    (gv = *gvp) && isGV_with_GP(gv) &&
 		    GvCVu(gv) && GvIMPORTED_CV(gv))
 		{
 		    ogv = gv;
@@ -5164,8 +5214,7 @@ Perl_yylex(pTHX)
 	    }
 	    else if (gv && !gvp
 		     && -tmp==KEY_lock	/* XXX generalizable kludge */
-		     && GvCVu(gv)
-		     && !hv_fetchs(GvHVn(PL_incgv), "Thread.pm", FALSE))
+		     && GvCVu(gv))
 	    {
 		tmp = 0;		/* any sub overrides "weak" keyword */
 	    }
@@ -5388,8 +5437,9 @@ Perl_yylex(pTHX)
 				    PL_nextwhite = 0;
 				}
 			    }
+			    else
 #endif
-			    goto its_constant;
+				goto its_constant;
 			}
 		    }
 #ifdef PERL_MAD
@@ -5436,7 +5486,7 @@ Perl_yylex(pTHX)
 				"Ambiguous use of -%s resolved as -&%s()",
 				PL_tokenbuf, PL_tokenbuf);
 		    /* Check for a constant sub */
-		    if ((sv = gv_const_sv(gv))) {
+		    if ((sv = gv_const_sv(gv)) && !PL_madskills) {
 		  its_constant:
 			SvREFCNT_dec(((SVOP*)yylval.opval)->op_sv);
 			((SVOP*)yylval.opval)->op_sv = SvREFCNT_inc_simple(sv);
@@ -5520,7 +5570,7 @@ Perl_yylex(pTHX)
 			}
 		    }
 		    if (probable_sub) {
-			gv = gv_fetchpv(PL_tokenbuf, TRUE, SVt_PVCV);
+			gv = gv_fetchpv(PL_tokenbuf, GV_ADD, SVt_PVCV);
 			op_free(yylval.opval);
 			yylval.opval = newCVREF(0, newGVOP(OP_GV, 0, gv));
 			yylval.opval->op_private |= OPpENTERSUB_NOPAREN;
@@ -6149,7 +6199,7 @@ Perl_yylex(pTHX)
 	case KEY_our:
 	case KEY_my:
 	case KEY_state:
-	    PL_in_my = tmp;
+	    PL_in_my = (U16)tmp;
 	    s = SKIPSPACE1(s);
 	    if (isIDFIRST_lazy_if(s,UTF)) {
 #ifdef PERL_MAD
@@ -6402,7 +6452,7 @@ Perl_yylex(pTHX)
 
 	case KEY_readpipe:
 	    set_csh();
-	    UNI(OP_BACKTICK);
+	    UNIDOR(OP_BACKTICK);
 
 	case KEY_rewinddir:
 	    UNI(OP_REWINDDIR);
@@ -6586,8 +6636,8 @@ Perl_yylex(pTHX)
 		    if (PL_madskills)
 			nametoke = newSVpvn(s, d - s);
 #endif
-		    if (strchr(tmpbuf, ':'))
-			sv_setpv(PL_subname, tmpbuf);
+		    if (memchr(tmpbuf, ':', len))
+			sv_setpvn(PL_subname, tmpbuf, len);
 		    else {
 			sv_setsv(PL_subname,PL_curstname);
 			sv_catpvs(PL_subname,"::");
@@ -6973,7 +7023,11 @@ S_pending_ident(pTHX)
     if (pit == '@' && PL_lex_state != LEX_NORMAL && !PL_lex_brackets) {
         GV *gv = gv_fetchpv(PL_tokenbuf+1, 0, SVt_PVAV);
         if ((!gv || ((PL_tokenbuf[0] == '@') ? !GvAV(gv) : !GvHV(gv)))
-             && ckWARN(WARN_AMBIGUOUS))
+		&& ckWARN(WARN_AMBIGUOUS)
+		/* DO NOT warn for @- and @+ */
+		&& !( PL_tokenbuf[2] == '\0' &&
+		    ( PL_tokenbuf[1] == '-' || PL_tokenbuf[1] == '+' ))
+	   )
         {
             /* Downgraded from fatal to warning 20000522 mjd */
             Perl_warner(aTHX_ packWARN(WARN_AMBIGUOUS),
@@ -10424,7 +10478,11 @@ S_checkcomma(pTHX_ const char *s, const char *name, const char *what)
 	    }
 	    while (isSPACE(*w))
 		++w;
-	    if (!*w || !strchr(";|})]oaiuw!=", *w))	/* an advisory hack only... */
+	    /* the list of chars below is for end of statements or
+	     * block / parens, boolean operators (&&, ||, //) and branch
+	     * constructs (or, and, if, until, unless, while, err, for).
+	     * Not a very solid hack... */
+	    if (!*w || !strchr(";&/|})]oaiuwef!=", *w))
 		Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
 			    "%s (...) interpreted as function",name);
 	}
@@ -10797,8 +10855,28 @@ S_scan_pat(pTHX_ char *start, I32 type)
     }
 
     pm = (PMOP*)newPMOP(type, 0);
-    if (PL_multi_open == '?')
+    if (PL_multi_open == '?') {
+	/* This is the only point in the code that sets PMf_ONCE:  */
 	pm->op_pmflags |= PMf_ONCE;
+
+	/* Hence it's safe to do this bit of PMOP book-keeping here, which
+	   allows us to restrict the list needed by reset to just the ??
+	   matches.  */
+	assert(type != OP_TRANS);
+	if (PL_curstash) {
+	    MAGIC *mg = mg_find((SV*)PL_curstash, PERL_MAGIC_symtab);
+	    U32 elements;
+	    if (!mg) {
+		mg = sv_magicext((SV*)PL_curstash, 0, PERL_MAGIC_symtab, 0, 0,
+				 0);
+	    }
+	    elements = mg->mg_len / sizeof(PMOP**);
+	    Renewc(mg->mg_ptr, elements + 1, PMOP*, char);
+	    ((PMOP**)mg->mg_ptr) [elements++] = pm;
+	    mg->mg_len = elements * sizeof(PMOP**);
+	    PmopSTASH_set(pm,PL_curstash);
+	}
+    }
 #ifdef PERL_MAD
     modstart = s;
 #endif
@@ -10818,8 +10896,6 @@ S_scan_pat(pTHX_ char *start, I32 type)
             "Use of /c modifier is meaningless without /g" );
     }
 
-    pm->op_pmpermflags = pm->op_pmflags;
-
     PL_lex_op = (OP*)pm;
     yylval.ival = OP_MATCH;
     return s;
@@ -10920,7 +10996,6 @@ S_scan_subst(pTHX_ char *start)
 	PL_lex_repl = repl;
     }
 
-    pm->op_pmpermflags = pm->op_pmflags;
     PL_lex_op = (OP*)pm;
     yylval.ival = OP_SUBST;
     return s;
@@ -11136,8 +11211,8 @@ S_scan_heredoc(pTHX_ register char *s)
 	s--;
 #endif
 
-    tmpstr = newSV(79);
-    sv_upgrade(tmpstr, SVt_PVIV);
+    tmpstr = newSV_type(SVt_PVIV);
+    SvGROW(tmpstr, 80);
     if (term == '\'') {
 	op_type = OP_CONST;
 	SvIV_set(tmpstr, -1);
@@ -11364,7 +11439,7 @@ S_scan_inputsymbol(pTHX_ char *start)
 		&& GvCVu(gv_readline) && GvIMPORTED_CV(gv_readline))
 		||
 		((gvp = (GV**)hv_fetchs(PL_globalstash, "readline", FALSE))
-		&& (gv_readline = *gvp) != (GV*)&PL_sv_undef
+		 && (gv_readline = *gvp) && isGV_with_GP(gv_readline)
 		&& GvCVu(gv_readline) && GvIMPORTED_CV(gv_readline)))
 	    readline_overriden = TRUE;
 
@@ -11542,8 +11617,8 @@ S_scan_str(pTHX_ char *start, int keep_quoted, int keep_delims)
 
     /* create a new SV to hold the contents.  79 is the SV's initial length.
        What a random number. */
-    sv = newSV(79);
-    sv_upgrade(sv, SVt_PVIV);
+    sv = newSV_type(SVt_PVIV);
+    SvGROW(sv, 80);
     SvIV_set(sv, termcode);
     (void)SvPOK_only(sv);		/* validate pointer */
 
@@ -12198,7 +12273,7 @@ Perl_scan_num(pTHX_ const char *start, YYSTYPE* lvalp)
     case 'v':
 vstring:
 		sv = newSV(5); /* preallocate storage space */
-		s = scan_vstring(s,sv);
+		s = scan_vstring(s, PL_bufend, sv);
 	break;
     }
 
@@ -12371,8 +12446,7 @@ Perl_start_subparse(pTHX_ I32 is_format, U32 flags)
     save_item(PL_subname);
     SAVESPTR(PL_compcv);
 
-    PL_compcv = (CV*)newSV(0);
-    sv_upgrade((SV *)PL_compcv, is_format ? SVt_PVFM : SVt_PVCV);
+    PL_compcv = (CV*)newSV_type(is_format ? SVt_PVFM : SVt_PVCV);
     CvFLAGS(PL_compcv) |= flags;
 
     PL_subline = CopLINE(PL_curcop);
@@ -12608,23 +12682,6 @@ S_swallow_bom(pTHX_ U8 *s)
     return (char*)s;
 }
 
-/*
- * restore_rsfp
- * Restore a source filter.
- */
-
-static void
-restore_rsfp(pTHX_ void *f)
-{
-    dVAR;
-    PerlIO * const fp = (PerlIO*)f;
-
-    if (PL_rsfp == PerlIO_stdin())
-	PerlIO_clearerr(PL_rsfp);
-    else if (PL_rsfp && (PL_rsfp != fp))
-	PerlIO_close(PL_rsfp);
-    PL_rsfp = fp;
-}
 
 #ifndef PERL_NO_UTF16_FILTER
 static I32
@@ -12681,28 +12738,29 @@ vstring, as well as updating the passed in sv.
 Function must be called like
 
 	sv = newSV(5);
-	s = scan_vstring(s,sv);
+	s = scan_vstring(s,e,sv);
 
+where s and e are the start and end of the string.
 The sv should already be large enough to store the vstring
 passed in, for performance reasons.
 
 */
 
 char *
-Perl_scan_vstring(pTHX_ const char *s, SV *sv)
+Perl_scan_vstring(pTHX_ const char *s, const char *e, SV *sv)
 {
     dVAR;
     const char *pos = s;
     const char *start = s;
     if (*pos == 'v') pos++;  /* get past 'v' */
-    while (pos < PL_bufend && (isDIGIT(*pos) || *pos == '_'))
+    while (pos < e && (isDIGIT(*pos) || *pos == '_'))
 	pos++;
     if ( *pos != '.') {
 	/* this may not be a v-string if followed by => */
 	const char *next = pos;
-	while (next < PL_bufend && isSPACE(*next))
+	while (next < e && isSPACE(*next))
 	    ++next;
-	if ((PL_bufend - next) >= 2 && *next == '=' && next[1] == '>' ) {
+	if ((e - next) >= 2 && *next == '=' && next[1] == '>' ) {
 	    /* return string not v-string */
 	    sv_setpvn(sv,(char *)s,pos-s);
 	    return (char *)pos;
@@ -12742,13 +12800,13 @@ Perl_scan_vstring(pTHX_ const char *s, SV *sv)
 	    sv_catpvn(sv, (const char*)tmpbuf, tmpend - tmpbuf);
 	    if (!UNI_IS_INVARIANT(NATIVE_TO_UNI(rev)))
 		 SvUTF8_on(sv);
-	    if (pos + 1 < PL_bufend && *pos == '.' && isDIGIT(pos[1]))
+	    if (pos + 1 < e && *pos == '.' && isDIGIT(pos[1]))
 		 s = ++pos;
 	    else {
 		 s = pos;
 		 break;
 	    }
-	    while (pos < PL_bufend && (isDIGIT(*pos) || *pos == '_'))
+	    while (pos < e && (isDIGIT(*pos) || *pos == '_'))
 		 pos++;
 	}
 	SvPOK_on(sv);