X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=mg.c;h=8cc9d85f43b185052e70e6b32491d47b0cdf3f1b;hb=79522dd28c2cdf92c115561db038e46cd34e5073;hp=5072a8f6f6745f2ae539d7d219971f085fbdcfdf;hpb=57d7c65eded7a5f963c5ce38ee196978a06e35df;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/mg.c b/mg.c
index 5072a8f..8cc9d85 100644
--- a/mg.c
+++ b/mg.c
@@ -1,7 +1,7 @@
 /*    mg.c
  *
  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- *    2000, 2001, 2002, 2003, 2004, 2005 by Larry Wall and others
+ *    2000, 2001, 2002, 2003, 2004, 2005, 2006, by Larry Wall and others
  *
  *    You may distribute under the terms of either the GNU General Public
  *    License or the Artistic License, as specified in the README file.
@@ -40,14 +40,17 @@ tie.
 #include "perl.h"
 
 #if defined(HAS_GETGROUPS) || defined(HAS_SETGROUPS)
-#  ifndef NGROUPS
-#    define NGROUPS 32
-#  endif
 #  ifdef I_GRP
 #    include <grp.h>
 #  endif
 #endif
 
+#if defined(HAS_SETGROUPS)
+#  ifndef NGROUPS
+#    define NGROUPS 32
+#  endif
+#endif
+
 #ifdef __hpux
 #  include <sys/pstat.h>
 #endif
@@ -80,13 +83,13 @@ struct magic_state {
 STATIC void
 S_save_magic(pTHX_ I32 mgs_ix, SV *sv)
 {
+    dVAR;
     MGS* mgs;
     assert(SvMAGICAL(sv));
-#ifdef PERL_OLD_COPY_ON_WRITE
-    /* Turning READONLY off for a copy-on-write scalar is a bad idea.  */
+    /* Turning READONLY off for a copy-on-write scalar (including shared
+       hash keys) is a bad idea.  */
     if (SvIsCOW(sv))
       sv_force_normal_flags(sv, 0);
-#endif
 
     SAVEDESTRUCTOR_X(S_restore_magic, INT2PTR(void*, (IV)mgs_ix));
 
@@ -97,7 +100,7 @@ S_save_magic(pTHX_ I32 mgs_ix, SV *sv)
 
     SvMAGICAL_off(sv);
     SvREADONLY_off(sv);
-    SvFLAGS(sv) |= (SvFLAGS(sv) & (SVp_NOK|SVp_POK)) >> PRIVSHIFT;
+    SvFLAGS(sv) |= (SvFLAGS(sv) & (SVp_IOK|SVp_NOK|SVp_POK)) >> PRIVSHIFT;
 }
 
 /*
@@ -112,6 +115,7 @@ void
 Perl_mg_magical(pTHX_ SV *sv)
 {
     const MAGIC* mg;
+    PERL_UNUSED_CONTEXT;
     for (mg = SvMAGIC(sv); mg; mg = mg->mg_moremagic) {
 	const MGVTBL* const vtbl = mg->mg_virtual;
 	if (vtbl) {
@@ -136,6 +140,7 @@ Do magic after a value is retrieved from the SV.  See C<sv_magic>.
 int
 Perl_mg_get(pTHX_ SV *sv)
 {
+    dVAR;
     const I32 mgs_ix = SSNEW(sizeof(MGS));
     const bool was_temp = (bool)SvTEMP(sv);
     int have_new = 0;
@@ -147,7 +152,7 @@ Perl_mg_get(pTHX_ SV *sv)
        cause the SV's buffer to get stolen (and maybe other stuff).
        So restore it.
     */
-    sv_2mortal(SvREFCNT_inc(sv));
+    sv_2mortal(SvREFCNT_inc_simple(sv));
     if (!was_temp) {
 	SvTEMP_off(sv);
     }
@@ -216,6 +221,7 @@ Do magic after a value is assigned to the SV.  See C<sv_magic>.
 int
 Perl_mg_set(pTHX_ SV *sv)
 {
+    dVAR;
     const I32 mgs_ix = SSNEW(sizeof(MGS));
     MAGIC* mg;
     MAGIC* nextmg;
@@ -248,6 +254,7 @@ Report on the SV's length.  See C<sv_magic>.
 U32
 Perl_mg_length(pTHX_ SV *sv)
 {
+    dVAR;
     MAGIC* mg;
     STRLEN len;
 
@@ -341,6 +348,7 @@ Finds the magic pointer for type matching the SV.  See C<sv_magic>.
 MAGIC*
 Perl_mg_find(pTHX_ const SV *sv, int type)
 {
+    PERL_UNUSED_CONTEXT;
     if (sv) {
         MAGIC *mg;
         for (mg = SvMAGIC(sv); mg; mg = mg->mg_moremagic) {
@@ -348,7 +356,7 @@ Perl_mg_find(pTHX_ const SV *sv, int type)
                 return mg;
         }
     }
-    return 0;
+    return NULL;
 }
 
 /*
@@ -399,9 +407,10 @@ doesn't (eg taint, pos).
 void
 Perl_mg_localize(pTHX_ SV *sv, SV *nsv)
 {
+    dVAR;
     MAGIC *mg;
     for (mg = SvMAGIC(sv); mg; mg = mg->mg_moremagic) {
-	const MGVTBL* const vtbl = mg->mg_virtual;
+	MGVTBL* const vtbl = mg->mg_virtual;
 	switch (mg->mg_type) {
 	/* value magic types: don't copy */
 	case PERL_MAGIC_bm:
@@ -427,15 +436,12 @@ Perl_mg_localize(pTHX_ SV *sv, SV *nsv)
 	    continue;
 	}
 		
-	if ((mg->mg_flags & MGf_COPY) && vtbl->svt_copy) {
-	    /* XXX calling the copy method is probably not correct. DAPM */
-	    (void)CALL_FPTR(vtbl->svt_copy)(aTHX_ sv, mg, nsv,
-				    mg->mg_ptr, mg->mg_len);
-	}
-	else {
+	if ((mg->mg_flags & MGf_LOCAL) && vtbl->svt_local)
+	    (void)CALL_FPTR(vtbl->svt_local)(aTHX_ nsv, mg);
+	else
 	    sv_magicext(nsv, mg->mg_obj, mg->mg_type, vtbl,
 			    mg->mg_ptr, mg->mg_len);
-	}
+
 	/* container types should remain read-only across localization */
 	SvFLAGS(nsv) |= SvREADONLY(sv);
     }
@@ -485,6 +491,7 @@ Perl_mg_free(pTHX_ SV *sv)
 U32
 Perl_magic_regdata_cnt(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     PERL_UNUSED_ARG(sv);
 
     if (PL_curpm) {
@@ -502,6 +509,7 @@ Perl_magic_regdata_cnt(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_regdatum_get(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     if (PL_curpm) {
 	register const REGEXP * const rx = PM_GETRE(PL_curpm);
 	if (rx) {
@@ -544,6 +552,7 @@ Perl_magic_regdatum_set(pTHX_ SV *sv, MAGIC *mg)
 U32
 Perl_magic_len(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     register I32 paren;
     register I32 i;
     register const REGEXP *rx;
@@ -634,10 +643,14 @@ Perl_magic_len(pTHX_ SV *sv, MAGIC *mg)
 }
 
 #define SvRTRIM(sv) STMT_START { \
-    STRLEN len = SvCUR(sv); \
-    while (len > 0 && isSPACE(SvPVX(sv)[len-1])) \
-	--len; \
-    SvCUR_set(sv, len); \
+    if (SvPOK(sv)) { \
+        STRLEN len = SvCUR(sv); \
+        char * const p = SvPVX(sv); \
+	while (len > 0 && isSPACE(p[len-1])) \
+	   --len; \
+	SvCUR_set(sv, len); \
+	p[len] = '\0'; \
+    } \
 } STMT_END
 
 int
@@ -669,15 +682,14 @@ Perl_magic_get(pTHX_ SV *sv, MAGIC *mg)
 	break;
     case '\005':  /* ^E */
 	 if (nextchar == '\0') {
-#ifdef MACOS_TRADITIONAL
+#if defined(MACOS_TRADITIONAL)
 	     {
 		  char msg[256];
 
 		  sv_setnv(sv,(double)gMacPerl_OSErr);
 		  sv_setpv(sv, gMacPerl_OSErr ? GetSysErrText(gMacPerl_OSErr, msg) : "");
 	     }
-#else
-#ifdef VMS
+#elif defined(VMS)
 	     {
 #	          include <descrip.h>
 #	          include <starlet.h>
@@ -689,8 +701,7 @@ Perl_magic_get(pTHX_ SV *sv, MAGIC *mg)
 		  else
 		       sv_setpvn(sv,"",0);
 	     }
-#else
-#ifdef OS2
+#elif defined(OS2)
 	     if (!(_emx_env & 0x200)) {	/* Under DOS */
 		  sv_setnv(sv, (NV)errno);
 		  sv_setpv(sv, errno ? Strerror(errno) : "");
@@ -703,8 +714,7 @@ Perl_magic_get(pTHX_ SV *sv, MAGIC *mg)
 		  sv_setnv(sv, (NV)Perl_rc);
 		  sv_setpv(sv, os2error(Perl_rc));
 	     }
-#else
-#ifdef WIN32
+#elif defined(WIN32)
 	     {
 		  DWORD dwErr = GetLastError();
 		  sv_setnv(sv, (NV)dwErr);
@@ -723,9 +733,6 @@ Perl_magic_get(pTHX_ SV *sv, MAGIC *mg)
 		 errno = saveerrno;
 	     }
 #endif
-#endif
-#endif
-#endif
 	     SvRTRIM(sv);
 	     SvNOK_on(sv);	/* what a wonderful hack! */
 	 }
@@ -808,7 +815,7 @@ Perl_magic_get(pTHX_ SV *sv, MAGIC *mg)
 		 * it could have been extended by warnings::register */
 		SV **bits_all;
 		HV * const bits=get_hv("warnings::Bits", FALSE);
-		if (bits && (bits_all=hv_fetch(bits, "all", 3, FALSE))) {
+		if (bits && (bits_all=hv_fetchs(bits, "all", FALSE))) {
 		    sv_setsv(sv, *bits_all);
 		}
 	        else {
@@ -838,12 +845,11 @@ Perl_magic_get(pTHX_ SV *sv, MAGIC *mg)
 	    {
 		i = t1 - s1;
 		s = rx->subbeg + s1;
-		if (!rx->subbeg)
-		    break;
+		assert(rx->subbeg);
 
 	      getrx:
 		if (i >= 0) {
-		    int oldtainted = PL_tainted;
+		    const int oldtainted = PL_tainted;
 		    TAINT_NOT;
 		    sv_setpvn(sv, s, i);
 		    PL_tainted = oldtainted;
@@ -994,29 +1000,22 @@ Perl_magic_get(pTHX_ SV *sv, MAGIC *mg)
 	break;
     case '(':
 	sv_setiv(sv, (IV)PL_gid);
-#ifdef HAS_GETGROUPS
-	Perl_sv_setpvf(aTHX_ sv, "%"Gid_t_f, (long unsigned int)PL_gid);
-#endif
 	goto add_groups;
     case ')':
 	sv_setiv(sv, (IV)PL_egid);
-#ifdef HAS_GETGROUPS
-	Perl_sv_setpvf(aTHX_ sv, "%"Gid_t_f, (long unsigned int)PL_egid);
-#endif
       add_groups:
 #ifdef HAS_GETGROUPS
 	{
 	    Groups_t *gary = NULL;
-	    I32 num_groups = getgroups(0, gary);
+	    I32 i, num_groups = getgroups(0, gary);
             Newx(gary, num_groups, Groups_t);
             num_groups = getgroups(num_groups, gary);
-	    while (--num_groups >= 0)
-		Perl_sv_catpvf(aTHX_ sv, " %"Gid_t_f,
-                    (long unsigned int)gary[num_groups]);
+	    for (i = 0; i < num_groups; i++)
+		Perl_sv_catpvf(aTHX_ sv, " %"IVdf, (IV)gary[i]);
             Safefree(gary);
 	}
-#endif
 	(void)SvIOK_on(sv);	/* what a wonderful hack! */
+#endif
 	break;
 #ifndef MACOS_TRADITIONAL
     case '0':
@@ -1040,20 +1039,17 @@ int
 Perl_magic_setenv(pTHX_ SV *sv, MAGIC *mg)
 {
     dVAR;
-    const char *s;
-    const char *ptr;
     STRLEN len, klen;
-
-    s = SvPV_const(sv,len);
-    ptr = MgPV_const(mg,klen);
+    const char *s = SvPV_const(sv,len);
+    const char * const ptr = MgPV_const(mg,klen);
     my_setenv(ptr, s);
 
 #ifdef DYNAMIC_ENV_FETCH
      /* We just undefd an environment var.  Is a replacement */
      /* waiting in the wings? */
     if (!len) {
-	SV **valp;
-	if ((valp = hv_fetch(GvHVn(PL_envgv), ptr, klen, FALSE)))
+	SV ** const valp = hv_fetch(GvHVn(PL_envgv), ptr, klen, FALSE);
+	if (valp)
 	    s = SvPV_const(*valp, len);
     }
 #endif
@@ -1081,7 +1077,7 @@ Perl_magic_setenv(pTHX_ SV *sv, MAGIC *mg)
 			    return 0;
 			}
 		    }
-		    if ((cp = strchr(elt, ':')) != Nullch)
+		    if ((cp = strchr(elt, ':')) != NULL)
 			*cp = '\0';
 		    if (my_trnlnm(elt, eltbuf, j++))
 			elt = eltbuf;
@@ -1120,13 +1116,14 @@ int
 Perl_magic_clearenv(pTHX_ SV *sv, MAGIC *mg)
 {
     PERL_UNUSED_ARG(sv);
-    my_setenv(MgPV_nolen_const(mg),Nullch);
+    my_setenv(MgPV_nolen_const(mg),NULL);
     return 0;
 }
 
 int
 Perl_magic_set_all_env(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     PERL_UNUSED_ARG(mg);
 #if defined(VMS)
     Perl_die(aTHX_ "Can't make list assignment to %%ENV on this system");
@@ -1171,6 +1168,7 @@ restore_sigmask(pTHX_ SV *save_sv)
 int
 Perl_magic_getsig(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     /* Are we fetching a signal entry? */
     const I32 i = whichsig(MgPV_nolen_const(mg));
     if (i > 0) {
@@ -1190,7 +1188,7 @@ Perl_magic_getsig(pTHX_ SV *sv, MAGIC *mg)
     	    	sv_setpv(sv,"IGNORE");
     	    else
     	    	sv_setsv(sv,&PL_sv_undef);
-    	    PL_psig_ptr[i] = SvREFCNT_inc(sv);
+	    PL_psig_ptr[i] = SvREFCNT_inc_simple(sv);
     	    SvTEMP_off(sv);
     	}
     }
@@ -1206,7 +1204,7 @@ Perl_magic_clearsig(pTHX_ SV *sv, MAGIC *mg)
     register const char * const s = MgPV_nolen_const(mg);
     PERL_UNUSED_ARG(sv);
     if (*s == '_') {
-	SV** svp = 0;
+	SV** svp = NULL;
 	if (strEQ(s,"__DIE__"))
 	    svp = &PL_diehook;
 	else if (strEQ(s,"__WARN__"))
@@ -1215,7 +1213,7 @@ Perl_magic_clearsig(pTHX_ SV *sv, MAGIC *mg)
 	    Perl_croak(aTHX_ "No such hook: %s", s);
 	if (svp && *svp) {
             SV * const to_dec = *svp;
-	    *svp = 0;
+	    *svp = NULL;
     	    SvREFCNT_dec(to_dec);
 	}
     }
@@ -1250,7 +1248,7 @@ Perl_magic_clearsig(pTHX_ SV *sv, MAGIC *mg)
     		PL_psig_name[i]=0;
     	    }
     	    if(PL_psig_ptr[i]) {
-                SV *to_dec=PL_psig_ptr[i];
+		SV * const to_dec=PL_psig_ptr[i];
     		PL_psig_ptr[i]=0;
 		LEAVE;
     		SvREFCNT_dec(to_dec);
@@ -1265,6 +1263,7 @@ Perl_magic_clearsig(pTHX_ SV *sv, MAGIC *mg)
 static void
 S_raise_signal(pTHX_ int sig)
 {
+    dVAR;
     /* Set a flag to say this signal is pending */
     PL_psig_pend[sig]++;
     /* And one to say _a_ signal is pending */
@@ -1327,6 +1326,7 @@ Perl_csighandler_init(void)
 void
 Perl_despatch_signals(pTHX)
 {
+    dVAR;
     int sig;
     PL_sig_pending = 0;
     for (sig = 1; sig < SIG_SIZE; sig++) {
@@ -1345,12 +1345,12 @@ Perl_magic_setsig(pTHX_ SV *sv, MAGIC *mg)
 {
     dVAR;
     I32 i;
-    SV** svp = 0;
+    SV** svp = NULL;
     /* Need to be careful with SvREFCNT_dec(), because that can have side
      * effects (due to closures). We must make sure that the new disposition
      * is in place before it is called.
      */
-    SV* to_dec = 0;
+    SV* to_dec = NULL;
     STRLEN len;
 #ifdef HAS_SIGPROCMASK
     sigset_t set, save;
@@ -1368,7 +1368,7 @@ Perl_magic_setsig(pTHX_ SV *sv, MAGIC *mg)
 	i = 0;
 	if (*svp) {
 	    to_dec = *svp;
-	    *svp = 0;
+	    *svp = NULL;
 	}
     }
     else {
@@ -1400,7 +1400,7 @@ Perl_magic_setsig(pTHX_ SV *sv, MAGIC *mg)
 #endif
 	SvREFCNT_dec(PL_psig_name[i]);
 	to_dec = PL_psig_ptr[i];
-	PL_psig_ptr[i] = SvREFCNT_inc(sv);
+	PL_psig_ptr[i] = SvREFCNT_inc_simple(sv);
 	SvTEMP_off(sv); /* Make sure it doesn't go away on us */
 	PL_psig_name[i] = newSVpvn(s, len);
 	SvREADONLY_on(PL_psig_name[i]);
@@ -1413,7 +1413,7 @@ Perl_magic_setsig(pTHX_ SV *sv, MAGIC *mg)
 #endif
 	}
 	else
-	    *svp = SvREFCNT_inc(sv);
+	    *svp = SvREFCNT_inc_simple_NN(sv);
 	if(to_dec)
 	    SvREFCNT_dec(to_dec);
 	return 0;
@@ -1447,11 +1447,11 @@ Perl_magic_setsig(pTHX_ SV *sv, MAGIC *mg)
 	 * tell whether HINT_STRICT_REFS is in force or not.
 	 */
 	if (!strchr(s,':') && !strchr(s,'\''))
-	    sv_insert(sv, 0, 0, "main::", 6);
+	    Perl_sv_insert(aTHX_ sv, 0, 0, STR_WITH_LEN("main::"));
 	if (i)
 	    (void)rsignal(i, PL_csighandlerp);
 	else
-	    *svp = SvREFCNT_inc(sv);
+	    *svp = SvREFCNT_inc_simple(sv);
     }
 #ifdef HAS_SIGPROCMASK
     if(i)
@@ -1466,6 +1466,7 @@ Perl_magic_setsig(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_setisa(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     PERL_UNUSED_ARG(sv);
     PERL_UNUSED_ARG(mg);
     PL_sub_generation++;
@@ -1475,6 +1476,7 @@ Perl_magic_setisa(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_setamagic(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     PERL_UNUSED_ARG(sv);
     PERL_UNUSED_ARG(mg);
     /* HV_badAMAGIC_on(Sv_STASH(sv)); */
@@ -1518,6 +1520,7 @@ Perl_magic_setnkeys(pTHX_ SV *sv, MAGIC *mg)
 STATIC int
 S_magic_methcall(pTHX_ SV *sv, const MAGIC *mg, const char *meth, I32 flags, int n, SV *val)
 {
+    dVAR;
     dSP;
 
     PUSHMARK(SP);
@@ -1694,6 +1697,7 @@ Perl_magic_scalarpack(pTHX_ HV *hv, MAGIC *mg)
 int
 Perl_magic_setdbline(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     GV * const gv = PL_DBline;
     const I32 i = SvTRUE(sv);
     SV ** const svp = av_fetch(GvAV(gv),
@@ -1714,6 +1718,7 @@ Perl_magic_setdbline(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_getarylen(pTHX_ SV *sv, const MAGIC *mg)
 {
+    dVAR;
     const AV * const obj = (AV*)mg->mg_obj;
     if (obj) {
 	sv_setiv(sv, AvFILL(obj) + PL_curcop->cop_arybase);
@@ -1726,6 +1731,7 @@ Perl_magic_getarylen(pTHX_ SV *sv, const MAGIC *mg)
 int
 Perl_magic_setarylen(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     AV * const obj = (AV*)mg->mg_obj;
     if (obj) {
 	av_fill(obj, SvIV(sv) - PL_curcop->cop_arybase);
@@ -1740,6 +1746,7 @@ Perl_magic_setarylen(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_freearylen_p(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     PERL_UNUSED_ARG(sv);
     /* during global destruction, mg_obj may already have been freed */
     if (PL_in_clean_all)
@@ -1761,6 +1768,7 @@ Perl_magic_freearylen_p(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_getpos(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     SV* const lsv = LvTARG(sv);
 
     if (SvTYPE(lsv) >= SVt_PVMG && SvMAGIC(lsv)) {
@@ -1780,6 +1788,7 @@ Perl_magic_getpos(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_setpos(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     SV* const lsv = LvTARG(sv);
     SSize_t pos;
     STRLEN len;
@@ -1792,7 +1801,7 @@ Perl_magic_setpos(pTHX_ SV *sv, MAGIC *mg)
     if (!mg) {
 	if (!SvOK(sv))
 	    return 0;
-	sv_magic(lsv, (SV*)0, PERL_MAGIC_regex_global, Nullch, 0);
+	sv_magic(lsv, NULL, PERL_MAGIC_regex_global, NULL, 0);
 	mg = mg_find(lsv, PERL_MAGIC_regex_global);
     }
     else if (!SvOK(sv)) {
@@ -1830,20 +1839,6 @@ Perl_magic_setpos(pTHX_ SV *sv, MAGIC *mg)
 }
 
 int
-Perl_magic_getglob(pTHX_ SV *sv, MAGIC *mg)
-{
-    PERL_UNUSED_ARG(mg);
-    if (SvFAKE(sv)) {			/* FAKE globs can get coerced */
-	SvFAKE_off(sv);
-	gv_efullname3(sv,((GV*)sv), "*");
-	SvFAKE_on(sv);
-    }
-    else
-	gv_efullname3(sv,((GV*)sv), "*");	/* a gv value, be nice */
-    return 0;
-}
-
-int
 Perl_magic_setglob(pTHX_ SV *sv, MAGIC *mg)
 {
     GV* gv;
@@ -1851,6 +1846,12 @@ Perl_magic_setglob(pTHX_ SV *sv, MAGIC *mg)
 
     if (!SvOK(sv))
 	return 0;
+    if (SvFLAGS(sv) & SVp_SCREAM
+	&& (SvTYPE(sv) == SVt_PVGV || SvTYPE(sv) == SVt_PVGV)) {
+	/* We're actually already a typeglob, so don't need the stuff below.
+	 */
+	return 0;
+    }
     gv =  gv_fetchsv(sv, GV_ADD, SVt_PVGV);
     if (sv == (SV*)gv)
 	return 0;
@@ -1885,6 +1886,7 @@ Perl_magic_getsubstr(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_setsubstr(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     STRLEN len;
     const char *tmps = SvPV_const(sv, len);
     SV * const lsv = LvTARG(sv);
@@ -1918,6 +1920,7 @@ Perl_magic_setsubstr(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_gettaint(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     PERL_UNUSED_ARG(sv);
     TAINT_IF((PL_localizing != 1) && (mg->mg_len & 1));
     return 0;
@@ -1926,6 +1929,7 @@ Perl_magic_gettaint(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_settaint(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     PERL_UNUSED_ARG(sv);
     /* update taint status unless we're restoring at scope exit */
     if (PL_localizing != 2) {
@@ -1943,12 +1947,11 @@ Perl_magic_getvec(pTHX_ SV *sv, MAGIC *mg)
     SV * const lsv = LvTARG(sv);
     PERL_UNUSED_ARG(mg);
 
-    if (!lsv) {
+    if (lsv)
+	sv_setuv(sv, do_vecget(lsv, LvTARGOFF(sv), LvTARGLEN(sv)));
+    else
 	SvOK_off(sv);
-	return 0;
-    }
 
-    sv_setuv(sv, do_vecget(lsv, LvTARGOFF(sv), LvTARGLEN(sv)));
     return 0;
 }
 
@@ -1963,7 +1966,8 @@ Perl_magic_setvec(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_getdefelem(pTHX_ SV *sv, MAGIC *mg)
 {
-    SV *targ = Nullsv;
+    dVAR;
+    SV *targ = NULL;
     if (LvTARGLEN(sv)) {
 	if (mg->mg_obj) {
 	    SV * const ahv = LvTARG(sv);
@@ -1979,10 +1983,10 @@ Perl_magic_getdefelem(pTHX_ SV *sv, MAGIC *mg)
 	if (targ && targ != &PL_sv_undef) {
 	    /* somebody else defined it for us */
 	    SvREFCNT_dec(LvTARG(sv));
-	    LvTARG(sv) = SvREFCNT_inc(targ);
+	    LvTARG(sv) = SvREFCNT_inc_simple_NN(targ);
 	    LvTARGLEN(sv) = 0;
 	    SvREFCNT_dec(mg->mg_obj);
-	    mg->mg_obj = Nullsv;
+	    mg->mg_obj = NULL;
 	    mg->mg_flags &= ~MGf_REFCOUNTED;
 	}
     }
@@ -2008,8 +2012,9 @@ Perl_magic_setdefelem(pTHX_ SV *sv, MAGIC *mg)
 void
 Perl_vivify_defelem(pTHX_ SV *sv)
 {
+    dVAR;
     MAGIC *mg;
-    SV *value = Nullsv;
+    SV *value = NULL;
 
     if (!LvTARGLEN(sv) || !(mg = mg_find(sv, PERL_MAGIC_defelem)))
 	return;
@@ -2024,66 +2029,32 @@ Perl_vivify_defelem(pTHX_ SV *sv)
     else {
 	AV* const av = (AV*)LvTARG(sv);
 	if ((I32)LvTARGLEN(sv) < 0 && (I32)LvTARGOFF(sv) > AvFILL(av))
-	    LvTARG(sv) = Nullsv;	/* array can't be extended */
+	    LvTARG(sv) = NULL;	/* array can't be extended */
 	else {
 	    SV** const svp = av_fetch(av, LvTARGOFF(sv), TRUE);
 	    if (!svp || (value = *svp) == &PL_sv_undef)
 		Perl_croak(aTHX_ PL_no_aelem, (I32)LvTARGOFF(sv));
 	}
     }
-    (void)SvREFCNT_inc(value);
+    SvREFCNT_inc_simple_void(value);
     SvREFCNT_dec(LvTARG(sv));
     LvTARG(sv) = value;
     LvTARGLEN(sv) = 0;
     SvREFCNT_dec(mg->mg_obj);
-    mg->mg_obj = Nullsv;
+    mg->mg_obj = NULL;
     mg->mg_flags &= ~MGf_REFCOUNTED;
 }
 
 int
 Perl_magic_killbackrefs(pTHX_ SV *sv, MAGIC *mg)
 {
-    AV *const av = (AV*)mg->mg_obj;
-    SV **svp = AvARRAY(av);
-    PERL_UNUSED_ARG(sv);
-
-    /* Not sure why the av can get freed ahead of its sv, but somehow it does
-       in ext/B/t/bytecode.t test 15 (involving print <DATA>)  */
-    if (svp && !SvIS_FREED(av)) {
-	SV *const *const last = svp + AvFILLp(av);
-
-	while (svp <= last) {
-	    if (*svp) {
-		SV *const referrer = *svp;
-		if (SvWEAKREF(referrer)) {
-		    /* XXX Should we check that it hasn't changed? */
-		    SvRV_set(referrer, 0);
-		    SvOK_off(referrer);
-		    SvWEAKREF_off(referrer);
-		} else if (SvTYPE(referrer) == SVt_PVGV ||
-			   SvTYPE(referrer) == SVt_PVLV) {
-		    /* You lookin' at me?  */
-		    assert(GvSTASH(referrer));
-		    assert(GvSTASH(referrer) == (HV*)sv);
-		    GvSTASH(referrer) = 0;
-		} else {
-		    Perl_croak(aTHX_
-			       "panic: magic_killbackrefs (flags=%"UVxf")",
-			       (UV)SvFLAGS(referrer));
-		}
-
-		*svp = Nullsv;
-	    }
-	    svp++;
-	}
-    }
-    SvREFCNT_dec(av); /* remove extra count added by sv_add_backref() */
-    return 0;
+    return Perl_sv_kill_backrefs(aTHX_ sv, (AV*)mg->mg_obj);
 }
 
 int
 Perl_magic_setmglob(pTHX_ SV *sv, MAGIC *mg)
 {
+    PERL_UNUSED_CONTEXT;
     mg->mg_len = -1;
     SvSCREAM_off(sv);
     return 0;
@@ -2128,6 +2099,7 @@ Perl_magic_setregexp(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_freeregexp(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     regexp * const re = (regexp *)mg->mg_obj;
     PERL_UNUSED_ARG(sv);
 
@@ -2143,6 +2115,7 @@ Perl_magic_setcollxfrm(pTHX_ SV *sv, MAGIC *mg)
      * RenE<eacute> Descartes said "I think not."
      * and vanished with a faint plop.
      */
+    PERL_UNUSED_CONTEXT;
     PERL_UNUSED_ARG(sv);
     if (mg->mg_ptr) {
 	Safefree(mg->mg_ptr);
@@ -2157,6 +2130,7 @@ Perl_magic_setcollxfrm(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_setutf8(pTHX_ SV *sv, MAGIC *mg)
 {
+    PERL_UNUSED_CONTEXT;
     PERL_UNUSED_ARG(sv);
     Safefree(mg->mg_ptr);	/* The mg_ptr holds the pos cache. */
     mg->mg_ptr = 0;
@@ -2167,6 +2141,7 @@ Perl_magic_setutf8(pTHX_ SV *sv, MAGIC *mg)
 int
 Perl_magic_set(pTHX_ SV *sv, MAGIC *mg)
 {
+    dVAR;
     register const char *s;
     I32 i;
     STRLEN len;
@@ -2215,7 +2190,7 @@ Perl_magic_set(pTHX_ SV *sv, MAGIC *mg)
 		PL_encoding = newSVsv(sv);
 	    }
 	    else {
-		PL_encoding = Nullsv;
+		PL_encoding = NULL;
 	    }
 	}
 	break;
@@ -2227,12 +2202,12 @@ Perl_magic_set(pTHX_ SV *sv, MAGIC *mg)
 	break;
     case '\011':	/* ^I */ /* NOT \t in EBCDIC */
 	Safefree(PL_inplace);
-	PL_inplace = SvOK(sv) ? savesvpv(sv) : Nullch;
+	PL_inplace = SvOK(sv) ? savesvpv(sv) : NULL;
 	break;
     case '\017':	/* ^O */
 	if (*(mg->mg_ptr+1) == '\0') {
 	    Safefree(PL_osname);
-	    PL_osname = Nullch;
+	    PL_osname = NULL;
 	    if (SvOK(sv)) {
 		TAINT_PROPER("assigning to $^O");
 		PL_osname = savesvpv(sv);
@@ -2357,7 +2332,7 @@ Perl_magic_set(pTHX_ SV *sv, MAGIC *mg)
 	    PL_ors_sv = newSVsv(sv);
 	}
 	else {
-	    PL_ors_sv = Nullsv;
+	    PL_ors_sv = NULL;
 	}
 	break;
     case ',':
@@ -2367,7 +2342,7 @@ Perl_magic_set(pTHX_ SV *sv, MAGIC *mg)
 	    PL_ofs_sv = newSVsv(sv);
 	}
 	else {
-	    PL_ofs_sv = Nullsv;
+	    PL_ofs_sv = NULL;
 	}
 	break;
     case '[':
@@ -2489,22 +2464,28 @@ Perl_magic_set(pTHX_ SV *sv, MAGIC *mg)
 #ifdef HAS_SETGROUPS
 	{
 	    const char *p = SvPV_const(sv, len);
-	    Groups_t gary[NGROUPS];
-
-	    while (isSPACE(*p))
-		++p;
-	    PL_egid = Atol(p);
-	    for (i = 0; i < NGROUPS; ++i) {
-		while (*p && !isSPACE(*p))
-		    ++p;
-		while (isSPACE(*p))
-		    ++p;
-		if (!*p)
-		    break;
-		gary[i] = Atol(p);
-	    }
-	    if (i)
-		(void)setgroups(i, gary);
+            Groups_t *gary = NULL;
+
+            while (isSPACE(*p))
+                ++p;
+            PL_egid = Atol(p);
+            for (i = 0; i < NGROUPS; ++i) {
+                while (*p && !isSPACE(*p))
+                    ++p;
+                while (isSPACE(*p))
+                    ++p;
+                if (!*p)
+                    break;
+                if(!gary)
+                    Newx(gary, i + 1, Groups_t);
+                else
+                    Renew(gary, i + 1, Groups_t);
+                gary[i] = Atol(p);
+            }
+            if (i)
+                (void)setgroups(i, gary);
+            if (gary)
+                Safefree(gary);
 	}
 #else  /* HAS_SETGROUPS */
 	PL_egid = SvIOK(sv) ? SvIVX(sv) : sv_2iv(sv);
@@ -2544,7 +2525,7 @@ Perl_magic_set(pTHX_ SV *sv, MAGIC *mg)
 	/* The BSDs don't show the argv[] in ps(1) output, they
 	 * show a string from the process struct and provide
 	 * the setproctitle() routine to manipulate that. */
-	{
+	if (PL_origalen != 1) {
 	    s = SvPV_const(sv, len);
 #   if __FreeBSD_version > 410001
 	    /* The leading "-" removes the "perl: " prefix,
@@ -2565,35 +2546,37 @@ Perl_magic_set(pTHX_ SV *sv, MAGIC *mg)
 	}
 #endif
 #if defined(__hpux) && defined(PSTAT_SETCMD)
-	{
+	if (PL_origalen != 1) {
 	     union pstun un;
 	     s = SvPV_const(sv, len);
 	     un.pst_command = (char *)s;
 	     pstat(PSTAT_SETCMD, un, len, 0, 0);
 	}
 #endif
-	/* PL_origalen is set in perl_parse(). */
-	s = SvPV_force(sv,len);
-	if (len >= (STRLEN)PL_origalen-1) {
-	    /* Longer than original, will be truncated. We assume that
-             * PL_origalen bytes are available. */
-	    Copy(s, PL_origargv[0], PL_origalen-1, char);
+	if (PL_origalen > 1) {
+	    /* PL_origalen is set in perl_parse(). */
+	    s = SvPV_force(sv,len);
+	    if (len >= (STRLEN)PL_origalen-1) {
+		/* Longer than original, will be truncated. We assume that
+		 * PL_origalen bytes are available. */
+		Copy(s, PL_origargv[0], PL_origalen-1, char);
+	    }
+	    else {
+		/* Shorter than original, will be padded. */
+		Copy(s, PL_origargv[0], len, char);
+		PL_origargv[0][len] = 0;
+		memset(PL_origargv[0] + len + 1,
+		       /* Is the space counterintuitive?  Yes.
+			* (You were expecting \0?)  
+			* Does it work?  Seems to.  (In Linux 2.4.20 at least.)
+			* --jhi */
+		       (int)' ',
+		       PL_origalen - len - 1);
+	    }
+	    PL_origargv[0][PL_origalen-1] = 0;
+	    for (i = 1; i < PL_origargc; i++)
+		PL_origargv[i] = 0;
 	}
-	else {
-	    /* Shorter than original, will be padded. */
-	    Copy(s, PL_origargv[0], len, char);
-	    PL_origargv[0][len] = 0;
-	    memset(PL_origargv[0] + len + 1,
-		   /* Is the space counterintuitive?  Yes.
-		    * (You were expecting \0?)  
-		    * Does it work?  Seems to.  (In Linux 2.4.20 at least.)
-		    * --jhi */
-		   (int)' ',
-		   PL_origalen - len - 1);
-	}
-	PL_origargv[0][PL_origalen-1] = 0;
-	for (i = 1; i < PL_origargc; i++)
-	    PL_origargv[i] = 0;
 	UNLOCK_DOLLARZERO_MUTEX;
 	break;
 #endif
@@ -2605,6 +2588,7 @@ I32
 Perl_whichsig(pTHX_ const char *sig)
 {
     register char* const* sigv;
+    PERL_UNUSED_CONTEXT;
 
     for (sigv = (char* const*)PL_sig_name; *sigv; sigv++)
 	if (strEQ(sig,*sigv))
@@ -2633,10 +2617,10 @@ Perl_sighandler(int sig)
     dTHX;
 #endif
     dSP;
-    GV *gv = Nullgv;
-    SV *sv = Nullsv;
+    GV *gv = NULL;
+    SV *sv = NULL;
     SV * const tSv = PL_Sv;
-    CV *cv = Nullcv;
+    CV *cv = NULL;
     OP *myop = PL_op;
     U32 flags = 0;
     XPV * const tXpv = PL_Xpv;
@@ -2682,7 +2666,7 @@ Perl_sighandler(int sig)
     }
 
     if(PL_psig_name[sig]) {
-    	sv = SvREFCNT_inc(PL_psig_name[sig]);
+	sv = SvREFCNT_inc_NN(PL_psig_name[sig]);
 	flags |= 64;
 #if !defined(PERL_IMPLICIT_CONTEXT)
 	PL_sig_sv = sv;
@@ -2751,7 +2735,7 @@ Perl_sighandler(int sig)
 	(void)rsignal(sig, PL_csighandlerp);
 #endif
 #endif /* !PERL_MICRO */
-	Perl_die(aTHX_ Nullch);
+	Perl_die(aTHX_ NULL);
     }
 cleanup:
     if (flags & 1)
@@ -2773,6 +2757,7 @@ cleanup:
 static void
 S_restore_magic(pTHX_ const void *p)
 {
+    dVAR;
     MGS* const mgs = SSPTR(PTR2IV(p), MGS*);
     SV* const sv = mgs->mgs_sv;
 
@@ -2834,7 +2819,6 @@ S_unwind_handler_stack(pTHX_ const void *p)
 
     if (flags & 1)
 	PL_savestack_ix -= 5; /* Unprotect save in progress. */
-    /* cxstack_ix-- Not needed, die already unwound it. */
 #if !defined(PERL_IMPLICIT_CONTEXT)
     if (flags & 64)
 	SvREFCNT_dec(PL_sig_sv);