X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=sv.c;h=029de83ca32da15e0172fcd00d1ab267fb38cd82;hb=37c25af0ec94b55a9d5be380e5f1703e0afca56b;hp=8800ddfe44dd68bda6bea8cd752edb6727a0db0c;hpb=34ba6322b644154d55680c95808981776852ae24;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/sv.c b/sv.c
index 8800ddf..029de83 100644
--- a/sv.c
+++ b/sv.c
@@ -1090,14 +1090,14 @@ Perl_sv_upgrade(pTHX_ register SV *sv, U32 new_type)
 
 	/* Could put this in the else clause below, as PVMG must have SvPVX
 	   0 already (the assertion above)  */
-	SvPV_set(sv, (char*)0);
+	SvPV_set(sv, NULL);
 
 	if (old_type >= SVt_PVMG) {
 	    SvMAGIC_set(sv, ((XPVMG*)old_body)->xmg_magic);
 	    SvSTASH_set(sv, ((XPVMG*)old_body)->xmg_stash);
 	} else {
-	    SvMAGIC_set(sv, 0);
-	    SvSTASH_set(sv, 0);
+	    SvMAGIC_set(sv, NULL);
+	    SvSTASH_set(sv, NULL);
 	}
 	break;
 
@@ -1149,10 +1149,11 @@ Perl_sv_upgrade(pTHX_ register SV *sv, U32 new_type)
 	if (new_type == SVt_PVIO)
 	    IoPAGE_LEN(sv) = 60;
 	if (old_type < SVt_RV)
-	    SvPV_set(sv, 0);
+	    SvPV_set(sv, NULL);
 	break;
     default:
-	Perl_croak(aTHX_ "panic: sv_upgrade to unknown type %lu", new_type);
+	Perl_croak(aTHX_ "panic: sv_upgrade to unknown type %lu",
+		   (unsigned long)new_type);
     }
 
     if (old_type_details->size) {
@@ -2924,6 +2925,175 @@ copy-ish functions and macros use this underneath.
 =cut
 */
 
+static void
+S_glob_assign(pTHX_ SV *dstr, SV *sstr, const int dtype)
+{
+    if (dtype != SVt_PVGV) {
+	const char * const name = GvNAME(sstr);
+	const STRLEN len = GvNAMELEN(sstr);
+	/* don't upgrade SVt_PVLV: it can hold a glob */
+	if (dtype != SVt_PVLV)
+	    sv_upgrade(dstr, SVt_PVGV);
+	sv_magic(dstr, dstr, PERL_MAGIC_glob, Nullch, 0);
+	GvSTASH(dstr) = GvSTASH(sstr);
+	if (GvSTASH(dstr))
+	    Perl_sv_add_backref(aTHX_ (SV*)GvSTASH(dstr), dstr);
+	GvNAME(dstr) = savepvn(name, len);
+	GvNAMELEN(dstr) = len;
+	SvFAKE_on(dstr);	/* can coerce to non-glob */
+    }
+
+#ifdef GV_UNIQUE_CHECK
+    if (GvUNIQUE((GV*)dstr)) {
+	Perl_croak(aTHX_ PL_no_modify);
+    }
+#endif
+
+    (void)SvOK_off(dstr);
+    GvINTRO_off(dstr);		/* one-shot flag */
+    gp_free((GV*)dstr);
+    GvGP(dstr) = gp_ref(GvGP(sstr));
+    if (SvTAINTED(sstr))
+	SvTAINT(dstr);
+    if (GvIMPORTED(dstr) != GVf_IMPORTED
+	&& CopSTASH_ne(PL_curcop, GvSTASH(dstr)))
+	{
+	    GvIMPORTED_on(dstr);
+	}
+    GvMULTI_on(dstr);
+    return;
+}
+
+static void
+S_pvgv_assign(pTHX_ SV *dstr, SV *sstr) {
+    SV * const sref = SvREFCNT_inc(SvRV(sstr));
+    SV *dref = NULL;
+    const int intro = GvINTRO(dstr);
+
+#ifdef GV_UNIQUE_CHECK
+    if (GvUNIQUE((GV*)dstr)) {
+	Perl_croak(aTHX_ PL_no_modify);
+    }
+#endif
+
+    if (intro) {
+	GvINTRO_off(dstr);	/* one-shot flag */
+	GvLINE(dstr) = CopLINE(PL_curcop);
+	GvEGV(dstr) = (GV*)dstr;
+    }
+    GvMULTI_on(dstr);
+    switch (SvTYPE(sref)) {
+    case SVt_PVAV:
+	if (intro)
+	    SAVEGENERICSV(GvAV(dstr));
+	else
+	    dref = (SV*)GvAV(dstr);
+	GvAV(dstr) = (AV*)sref;
+	if (!GvIMPORTED_AV(dstr)
+	    && CopSTASH_ne(PL_curcop, GvSTASH(dstr)))
+	    {
+		GvIMPORTED_AV_on(dstr);
+	    }
+	break;
+    case SVt_PVHV:
+	if (intro)
+	    SAVEGENERICSV(GvHV(dstr));
+	else
+	    dref = (SV*)GvHV(dstr);
+	GvHV(dstr) = (HV*)sref;
+	if (!GvIMPORTED_HV(dstr)
+	    && CopSTASH_ne(PL_curcop, GvSTASH(dstr)))
+	    {
+		GvIMPORTED_HV_on(dstr);
+	    }
+	break;
+    case SVt_PVCV:
+	if (intro) {
+	    if (GvCVGEN(dstr) && GvCV(dstr) != (CV*)sref) {
+		SvREFCNT_dec(GvCV(dstr));
+		GvCV(dstr) = Nullcv;
+		GvCVGEN(dstr) = 0; /* Switch off cacheness. */
+		PL_sub_generation++;
+	    }
+	    SAVEGENERICSV(GvCV(dstr));
+	}
+	else
+	    dref = (SV*)GvCV(dstr);
+	if (GvCV(dstr) != (CV*)sref) {
+	    CV* const cv = GvCV(dstr);
+	    if (cv) {
+		if (!GvCVGEN((GV*)dstr) &&
+		    (CvROOT(cv) || CvXSUB(cv)))
+		    {
+			/* Redefining a sub - warning is mandatory if
+			   it was a const and its value changed. */
+			if (CvCONST(cv)	&& CvCONST((CV*)sref)
+			    && cv_const_sv(cv) == cv_const_sv((CV*)sref)) {
+			    /* They are 2 constant subroutines generated from
+			       the same constant. This probably means that
+			       they are really the "same" proxy subroutine
+			       instantiated in 2 places. Most likely this is
+			       when a constant is exported twice.  Don't warn.
+			    */
+			}
+			else if (ckWARN(WARN_REDEFINE)
+				 || (CvCONST(cv)
+				     && (!CvCONST((CV*)sref)
+					 || sv_cmp(cv_const_sv(cv),
+						   cv_const_sv((CV*)sref))))) {
+			    Perl_warner(aTHX_ packWARN(WARN_REDEFINE),
+					CvCONST(cv)
+					? "Constant subroutine %s::%s redefined"
+					: "Subroutine %s::%s redefined",
+					HvNAME_get(GvSTASH((GV*)dstr)),
+					GvENAME((GV*)dstr));
+			}
+		    }
+		if (!intro)
+		    cv_ckproto(cv, (GV*)dstr,
+			       SvPOK(sref) ? SvPVX_const(sref) : Nullch);
+	    }
+	    GvCV(dstr) = (CV*)sref;
+	    GvCVGEN(dstr) = 0; /* Switch off cacheness. */
+	    GvASSUMECV_on(dstr);
+	    PL_sub_generation++;
+	}
+	if (!GvIMPORTED_CV(dstr) && CopSTASH_ne(PL_curcop, GvSTASH(dstr))) {
+	    GvIMPORTED_CV_on(dstr);
+	}
+	break;
+    case SVt_PVIO:
+	if (intro)
+	    SAVEGENERICSV(GvIOp(dstr));
+	else
+	    dref = (SV*)GvIOp(dstr);
+	GvIOp(dstr) = (IO*)sref;
+	break;
+    case SVt_PVFM:
+	if (intro)
+	    SAVEGENERICSV(GvFORM(dstr));
+	else
+	    dref = (SV*)GvFORM(dstr);
+	GvFORM(dstr) = (CV*)sref;
+	break;
+    default:
+	if (intro)
+	    SAVEGENERICSV(GvSV(dstr));
+	else
+	    dref = (SV*)GvSV(dstr);
+	GvSV(dstr) = sref;
+	if (!GvIMPORTED_SV(dstr) && CopSTASH_ne(PL_curcop, GvSTASH(dstr))) {
+	    GvIMPORTED_SV_on(dstr);
+	}
+	break;
+    }
+    if (dref)
+	SvREFCNT_dec(dref);
+    if (SvTAINTED(sstr))
+	SvTAINT(dstr);
+    return;
+}
+
 void
 Perl_sv_setsv_flags(pTHX_ SV *dstr, register SV *sstr, I32 flags)
 {
@@ -2976,8 +3146,11 @@ Perl_sv_setsv_flags(pTHX_ SV *dstr, register SV *sstr, I32 flags)
 	    SvIV_set(dstr,  SvIVX(sstr));
 	    if (SvIsUV(sstr))
 		SvIsUV_on(dstr);
-	    if (SvTAINTED(sstr))
-		SvTAINT(dstr);
+	    /* SvTAINTED can only be true if the SV has taint magic, which in
+	       turn means that the SV type is PVMG (or greater). This is the
+	       case statement for SVt_IV, so this cannot be true (whatever gcov
+	       may say).  */
+	    assert(!SvTAINTED(sstr));
 	    return;
 	}
 	goto undef_sstr;
@@ -2997,8 +3170,11 @@ Perl_sv_setsv_flags(pTHX_ SV *dstr, register SV *sstr, I32 flags)
 	    }
 	    SvNV_set(dstr, SvNVX(sstr));
 	    (void)SvNOK_only(dstr);
-	    if (SvTAINTED(sstr))
-		SvTAINT(dstr);
+	    /* SvTAINTED can only be true if the SV has taint magic, which in
+	       turn means that the SV type is PVMG (or greater). This is the
+	       case statement for SVt_NV, so this cannot be true (whatever gcov
+	       may say).  */
+	    assert(!SvTAINTED(sstr));
 	    return;
 	}
 	goto undef_sstr;
@@ -3018,7 +3194,8 @@ Perl_sv_setsv_flags(pTHX_ SV *dstr, register SV *sstr, I32 flags)
 		GvMULTI_on(dstr);
 		return;
 	    }
-	    goto glob_assign;
+	    S_glob_assign(aTHX_ dstr, sstr, dtype);
+	    return;
 	}
 	break;
     case SVt_PVFM:
@@ -3057,40 +3234,7 @@ Perl_sv_setsv_flags(pTHX_ SV *dstr, register SV *sstr, I32 flags)
 
     case SVt_PVGV:
 	if (dtype <= SVt_PVGV) {
-  glob_assign:
-	    if (dtype != SVt_PVGV) {
-		const char * const name = GvNAME(sstr);
-		const STRLEN len = GvNAMELEN(sstr);
-		/* don't upgrade SVt_PVLV: it can hold a glob */
-		if (dtype != SVt_PVLV)
-		    sv_upgrade(dstr, SVt_PVGV);
-		sv_magic(dstr, dstr, PERL_MAGIC_glob, Nullch, 0);
-		GvSTASH(dstr) = GvSTASH(sstr);
-		if (GvSTASH(dstr))
-		    Perl_sv_add_backref(aTHX_ (SV*)GvSTASH(dstr), dstr);
-		GvNAME(dstr) = savepvn(name, len);
-		GvNAMELEN(dstr) = len;
-		SvFAKE_on(dstr);	/* can coerce to non-glob */
-	    }
-
-#ifdef GV_UNIQUE_CHECK
-                if (GvUNIQUE((GV*)dstr)) {
-                    Perl_croak(aTHX_ PL_no_modify);
-                }
-#endif
-
-	    (void)SvOK_off(dstr);
-	    GvINTRO_off(dstr);		/* one-shot flag */
-	    gp_free((GV*)dstr);
-	    GvGP(dstr) = gp_ref(GvGP(sstr));
-	    if (SvTAINTED(sstr))
-		SvTAINT(dstr);
-	    if (GvIMPORTED(dstr) != GVf_IMPORTED
-		&& CopSTASH_ne(PL_curcop, GvSTASH(dstr)))
-	    {
-		GvIMPORTED_on(dstr);
-	    }
-	    GvMULTI_on(dstr);
+	    S_glob_assign(aTHX_ dstr, sstr, dtype);
 	    return;
 	}
 	/* FALL THROUGH */
@@ -3100,8 +3244,10 @@ Perl_sv_setsv_flags(pTHX_ SV *dstr, register SV *sstr, I32 flags)
 	    mg_get(sstr);
 	    if ((int)SvTYPE(sstr) != stype) {
 		stype = SvTYPE(sstr);
-		if (stype == SVt_PVGV && dtype <= SVt_PVGV)
-		    goto glob_assign;
+		if (stype == SVt_PVGV && dtype <= SVt_PVGV) {
+		    S_glob_assign(aTHX_ dstr, sstr, dtype);
+		    return;
+		}
 	    }
 	}
 	if (stype == SVt_PVLV)
@@ -3115,139 +3261,7 @@ Perl_sv_setsv_flags(pTHX_ SV *dstr, register SV *sstr, I32 flags)
     if (sflags & SVf_ROK) {
 	if (dtype >= SVt_PV) {
 	    if (dtype == SVt_PVGV) {
-		SV * const sref = SvREFCNT_inc(SvRV(sstr));
-		SV *dref = NULL;
-		const int intro = GvINTRO(dstr);
-
-#ifdef GV_UNIQUE_CHECK
-                if (GvUNIQUE((GV*)dstr)) {
-                    Perl_croak(aTHX_ PL_no_modify);
-                }
-#endif
-
-		if (intro) {
-		    GvINTRO_off(dstr);	/* one-shot flag */
-		    GvLINE(dstr) = CopLINE(PL_curcop);
-		    GvEGV(dstr) = (GV*)dstr;
-		}
-		GvMULTI_on(dstr);
-		switch (SvTYPE(sref)) {
-		case SVt_PVAV:
-		    if (intro)
-			SAVEGENERICSV(GvAV(dstr));
-		    else
-			dref = (SV*)GvAV(dstr);
-		    GvAV(dstr) = (AV*)sref;
-		    if (!GvIMPORTED_AV(dstr)
-			&& CopSTASH_ne(PL_curcop, GvSTASH(dstr)))
-		    {
-			GvIMPORTED_AV_on(dstr);
-		    }
-		    break;
-		case SVt_PVHV:
-		    if (intro)
-			SAVEGENERICSV(GvHV(dstr));
-		    else
-			dref = (SV*)GvHV(dstr);
-		    GvHV(dstr) = (HV*)sref;
-		    if (!GvIMPORTED_HV(dstr)
-			&& CopSTASH_ne(PL_curcop, GvSTASH(dstr)))
-		    {
-			GvIMPORTED_HV_on(dstr);
-		    }
-		    break;
-		case SVt_PVCV:
-		    if (intro) {
-			if (GvCVGEN(dstr) && GvCV(dstr) != (CV*)sref) {
-			    SvREFCNT_dec(GvCV(dstr));
-			    GvCV(dstr) = Nullcv;
-			    GvCVGEN(dstr) = 0; /* Switch off cacheness. */
-			    PL_sub_generation++;
-			}
-			SAVEGENERICSV(GvCV(dstr));
-		    }
-		    else
-			dref = (SV*)GvCV(dstr);
-		    if (GvCV(dstr) != (CV*)sref) {
-			CV* const cv = GvCV(dstr);
-			if (cv) {
-			    if (!GvCVGEN((GV*)dstr) &&
-				(CvROOT(cv) || CvXSUB(cv)))
-			    {
- 				/* Redefining a sub - warning is mandatory if
- 				   it was a const and its value changed. */
-				if (CvCONST(cv)	&& CvCONST((CV*)sref)
-				    && cv_const_sv(cv)
-				    == cv_const_sv((CV*)sref)) {
-				    /* They are 2 constant subroutines
-				       generated from the same constant.
-				       This probably means that they are
-				       really the "same" proxy subroutine
-				       instantiated in 2 places. Most likely
-				       this is when a constant is exported
-				       twice.  Don't warn.  */
-				}
-				else if (ckWARN(WARN_REDEFINE)
- 				    || (CvCONST(cv)
- 					&& (!CvCONST((CV*)sref)
- 					    || sv_cmp(cv_const_sv(cv),
- 						      cv_const_sv((CV*)sref)))))
- 				{
- 				    Perl_warner(aTHX_ packWARN(WARN_REDEFINE),
- 					CvCONST(cv)
- 					? "Constant subroutine %s::%s redefined"
- 					: "Subroutine %s::%s redefined",
-					HvNAME_get(GvSTASH((GV*)dstr)),
- 					GvENAME((GV*)dstr));
- 				}
-			    }
-			    if (!intro)
-				cv_ckproto(cv, (GV*)dstr,
-					   SvPOK(sref)
-					   ? SvPVX_const(sref) : Nullch);
-			}
-			GvCV(dstr) = (CV*)sref;
-			GvCVGEN(dstr) = 0; /* Switch off cacheness. */
-			GvASSUMECV_on(dstr);
-			PL_sub_generation++;
-		    }
-		    if (!GvIMPORTED_CV(dstr)
-			&& CopSTASH_ne(PL_curcop, GvSTASH(dstr)))
-		    {
-			GvIMPORTED_CV_on(dstr);
-		    }
-		    break;
-		case SVt_PVIO:
-		    if (intro)
-			SAVEGENERICSV(GvIOp(dstr));
-		    else
-			dref = (SV*)GvIOp(dstr);
-		    GvIOp(dstr) = (IO*)sref;
-		    break;
-		case SVt_PVFM:
-		    if (intro)
-			SAVEGENERICSV(GvFORM(dstr));
-		    else
-			dref = (SV*)GvFORM(dstr);
-		    GvFORM(dstr) = (CV*)sref;
-		    break;
-		default:
-		    if (intro)
-			SAVEGENERICSV(GvSV(dstr));
-		    else
-			dref = (SV*)GvSV(dstr);
-		    GvSV(dstr) = sref;
-		    if (!GvIMPORTED_SV(dstr)
-			&& CopSTASH_ne(PL_curcop, GvSTASH(dstr)))
-		    {
-			GvIMPORTED_SV_on(dstr);
-		    }
-		    break;
-		}
-		if (dref)
-		    SvREFCNT_dec(dref);
-		if (SvTAINTED(sstr))
-		    SvTAINT(dstr);
+		S_pvgv_assign(aTHX_ dstr, sstr);
 		return;
 	    }
 	    if (SvPVX_const(dstr)) {
@@ -3258,25 +3272,18 @@ Perl_sv_setsv_flags(pTHX_ SV *dstr, register SV *sstr, I32 flags)
 	}
 	(void)SvOK_off(dstr);
 	SvRV_set(dstr, SvREFCNT_inc(SvRV(sstr)));
-	SvROK_on(dstr);
+	SvFLAGS(dstr) |= sflags & (SVf_IOK|SVp_IOK|SVf_NOK|SVp_NOK|SVf_ROK
+				   |SVf_AMAGIC);
 	if (sflags & SVp_NOK) {
-	    SvNOKp_on(dstr);
-	    /* Only set the public OK flag if the source has public OK.  */
-	    if (sflags & SVf_NOK)
-		SvFLAGS(dstr) |= SVf_NOK;
 	    SvNV_set(dstr, SvNVX(sstr));
 	}
 	if (sflags & SVp_IOK) {
-	    (void)SvIOKp_on(dstr);
-	    if (sflags & SVf_IOK)
-		SvFLAGS(dstr) |= SVf_IOK;
+	    /* Must do this otherwise some other overloaded use of 0x80000000
+	       gets confused. Probably 0x80000000 */
 	    if (sflags & SVf_IVisUV)
 		SvIsUV_on(dstr);
 	    SvIV_set(dstr, SvIVX(sstr));
 	}
-	if (SvAMAGIC(sstr)) {
-	    SvAMAGIC_on(dstr);
-	}
     }
     else if (sflags & SVp_POK) {
         bool isSwipe = 0;
@@ -3393,63 +3400,45 @@ Perl_sv_setsv_flags(pTHX_ SV *dstr, register SV *sstr, I32 flags)
 
                 SvTEMP_off(dstr);
                 (void)SvOK_off(sstr);	/* NOTE: nukes most SvFLAGS on sstr */
-                SvPV_set(sstr, Nullch);
+                SvPV_set(sstr, NULL);
                 SvLEN_set(sstr, 0);
                 SvCUR_set(sstr, 0);
                 SvTEMP_off(sstr);
             }
         }
-	if (sflags & SVf_UTF8)
-	    SvUTF8_on(dstr);
 	if (sflags & SVp_NOK) {
-	    SvNOKp_on(dstr);
-	    if (sflags & SVf_NOK)
-		SvFLAGS(dstr) |= SVf_NOK;
 	    SvNV_set(dstr, SvNVX(sstr));
 	}
 	if (sflags & SVp_IOK) {
-	    (void)SvIOKp_on(dstr);
-	    if (sflags & SVf_IOK)
-		SvFLAGS(dstr) |= SVf_IOK;
+	    SvRELEASE_IVX(dstr);
+	    SvIV_set(dstr, SvIVX(sstr));
+	    /* Must do this otherwise some other overloaded use of 0x80000000
+	       gets confused. I guess SVpbm_VALID */
 	    if (sflags & SVf_IVisUV)
 		SvIsUV_on(dstr);
-	    SvIV_set(dstr, SvIVX(sstr));
 	}
-	if (SvVOK(sstr)) {
-	    const MAGIC * const smg = mg_find(sstr,PERL_MAGIC_vstring);
-	    sv_magic(dstr, NULL, PERL_MAGIC_vstring,
-			smg->mg_ptr, smg->mg_len);
-	    SvRMAGICAL_on(dstr);
+	SvFLAGS(dstr) |= sflags & (SVf_IOK|SVp_IOK|SVf_NOK|SVp_NOK|SVf_UTF8);
+	{
+	    const MAGIC * const smg = SvVOK(sstr);
+	    if (smg) {
+		sv_magic(dstr, NULL, PERL_MAGIC_vstring,
+			 smg->mg_ptr, smg->mg_len);
+		SvRMAGICAL_on(dstr);
+	    }
 	}
     }
-    else if (sflags & SVp_IOK) {
-	if (sflags & SVf_IOK)
-	    (void)SvIOK_only(dstr);
-	else {
-	    (void)SvOK_off(dstr);
-	    (void)SvIOKp_on(dstr);
+    else if (sflags & (SVp_IOK|SVp_NOK)) {
+	(void)SvOK_off(dstr);
+	SvFLAGS(dstr) |= sflags & (SVf_IOK|SVp_IOK|SVf_IVisUV|SVf_NOK|SVp_NOK);
+	if (sflags & SVp_IOK) {
+	    /* XXXX Do we want to set IsUV for IV(ROK)?  Be extra safe... */
+	    SvIV_set(dstr, SvIVX(sstr));
 	}
-	/* XXXX Do we want to set IsUV for IV(ROK)?  Be extra safe... */
-	if (sflags & SVf_IVisUV)
-	    SvIsUV_on(dstr);
-	SvIV_set(dstr, SvIVX(sstr));
 	if (sflags & SVp_NOK) {
-	    if (sflags & SVf_NOK)
-		(void)SvNOK_on(dstr);
-	    else
-		(void)SvNOKp_on(dstr);
+	    SvFLAGS(dstr) |= sflags & (SVf_NOK|SVp_NOK);
 	    SvNV_set(dstr, SvNVX(sstr));
 	}
     }
-    else if (sflags & SVp_NOK) {
-	if (sflags & SVf_NOK)
-	    (void)SvNOK_only(dstr);
-	else {
-	    (void)SvOK_off(dstr);
-	    SvNOKp_on(dstr);
-	}
-	SvNV_set(dstr, SvNVX(sstr));
-    }
     else {
 	if (dtype == SVt_PVGV) {
 	    if (ckWARN(WARN_MISC))
@@ -3780,7 +3769,7 @@ Perl_sv_force_normal_flags(pTHX_ register SV *sv, U32 flags)
             SvFAKE_off(sv);
             SvREADONLY_off(sv);
             /* This SV doesn't own the buffer, so need to Newx() a new one:  */
-            SvPV_set(sv, (char*)0);
+            SvPV_set(sv, NULL);
             SvLEN_set(sv, 0);
             if (flags & SV_COW_DROP_PV) {
                 /* OK, so we don't need to copy our buffer.  */
@@ -4012,9 +4001,16 @@ Perl_sv_catpv_mg(pTHX_ register SV *sv, register const char *ptr)
 /*
 =for apidoc newSV
 
-Create a new null SV, or if len > 0, create a new empty SVt_PV type SV
-with an initial PV allocation of len+1. Normally accessed via the C<NEWSV>
-macro.
+Creates a new SV.  A non-zero C<len> parameter indicates the number of
+bytes of preallocated string space the SV should have.  An extra byte for a
+trailing NUL is also reserved.  (SvPOK is not set for the SV even if string
+space is allocated.)  The reference count for the new SV is set to 1.
+
+In 5.9.3, newSV() replaces the older NEWSV() API, and drops the first
+parameter, I<x>, a debug aid which allowed callers to identify themselves.
+This aid has been superseded by a new build option, PERL_MEM_LOG (see
+L<perlhack/PERL_MEM_LOG>).  The older API is still there for use in XS
+modules supporting older perls.
 
 =cut
 */
@@ -4052,7 +4048,7 @@ to contain an C<SV*> and is stored as-is with its REFCNT incremented.
 =cut
 */
 MAGIC *	
-Perl_sv_magicext(pTHX_ SV* sv, SV* obj, int how, const MGVTBL *vtable,
+Perl_sv_magicext(pTHX_ SV* sv, SV* obj, int how, MGVTBL *vtable,
 		 const char* name, I32 namlen)
 {
     dVAR;
@@ -4141,7 +4137,7 @@ void
 Perl_sv_magic(pTHX_ register SV *sv, SV *obj, int how, const char *name, I32 namlen)
 {
     dVAR;
-    const MGVTBL *vtable;
+    MGVTBL *vtable;
     MAGIC* mg;
 
 #ifdef PERL_OLD_COPY_ON_WRITE
@@ -5760,7 +5756,7 @@ Perl_sv_gets(pTHX_ register SV *sv, register PerlIO *fp, I32 append)
 		sv_pos_u2b(sv,&append,0);
 	    }
 	} else if (SvUTF8(sv)) {
-	    SV * const tsv = NEWSV(0,0);
+	    SV * const tsv = newSV(0);
 	    sv_gets(tsv, fp, 0);
 	    sv_utf8_upgrade_nomg(tsv);
 	    SvCUR_set(sv,append);
@@ -6950,7 +6946,7 @@ Perl_sv_2cv(pTHX_ SV *sv, HV **st, GV **gvp, I32 lref)
 	if (lref && !GvCVu(gv)) {
 	    SV *tmpsv;
 	    ENTER;
-	    tmpsv = NEWSV(704,0);
+	    tmpsv = newSV(0);
 	    gv_efullname3(tmpsv, gv, Nullch);
 	    /* XXX this is probably not what they think they're getting.
 	     * It has the same effect as "sub name;", i.e. just a forward
@@ -8938,8 +8934,8 @@ ptr_table_* functions.
 #define io_dup_inc(s,t)	(IO*)SvREFCNT_inc(sv_dup((SV*)s,t))
 #define gv_dup(s,t)	(GV*)sv_dup((SV*)s,t)
 #define gv_dup_inc(s,t)	(GV*)SvREFCNT_inc(sv_dup((SV*)s,t))
-#define SAVEPV(p)	(p ? savepv(p) : Nullch)
-#define SAVEPVN(p,n)	(p ? savepvn(p,n) : Nullch)
+#define SAVEPV(p)	((p) ? savepv(p) : NULL)
+#define SAVEPVN(p,n)	((p) ? savepvn(p,n) : NULL)
 
 
 /* Duplicate a regexp. Required reading: pregcomp() and pregfree() in
@@ -9371,7 +9367,7 @@ Perl_rvpv_dup(pTHX_ SV *dstr, const SV *sstr, CLONE_PARAMS* param)
 	if (SvTYPE(dstr) == SVt_RV)
 	    SvRV_set(dstr, NULL);
 	else
-	    SvPV_set(dstr, 0);
+	    SvPV_set(dstr, NULL);
     }
 }
 
@@ -9384,7 +9380,7 @@ Perl_sv_dup(pTHX_ const SV *sstr, CLONE_PARAMS* param)
     SV *dstr;
 
     if (!sstr || SvTYPE(sstr) == SVTYPEMASK)
-	return Nullsv;
+	return NULL;
     /* look for it in the table first */
     dstr = (SV*)ptr_table_fetch(PL_ptr_table, sstr);
     if (dstr)
@@ -10643,7 +10639,7 @@ perl_clone_using(PerlInterpreter *proto_perl, UV flags,
 	PL_linestart	= SvPVX(PL_linestr) + (i < 0 ? 0 : i);
     }
     else {
-        PL_linestr = NEWSV(65,79);
+        PL_linestr = newSV(79);
         sv_upgrade(PL_linestr,SVt_PVIV);
         sv_setpvn(PL_linestr,"",0);
 	PL_bufptr = PL_oldbufptr = PL_oldoldbufptr = PL_linestart = SvPVX(PL_linestr);
@@ -10850,7 +10846,7 @@ perl_clone_using(PerlInterpreter *proto_perl, UV flags,
 	 * orphaned
 	 */
 	for (i = 0; i<= proto_perl->Ttmps_ix; i++) {
-	    SV *nsv = (SV*)ptr_table_fetch(PL_ptr_table,
+	    SV * const nsv = (SV*)ptr_table_fetch(PL_ptr_table,
 		    proto_perl->Ttmps_stack[i]);
 	    if (nsv && !SvREFCNT(nsv)) {
 		EXTEND_MORTAL(1);
@@ -11238,7 +11234,7 @@ S_varname(pTHX_ GV *gv, const char gvtype, PADOFFSET targ,
     }
 
     if (subscript_type == FUV_SUBSCRIPT_HASH) {
-	SV * const sv = NEWSV(0,0);
+	SV * const sv = newSV(0);
 	*SvPVX(name) = '$';
 	Perl_sv_catpvf(aTHX_ name, "{%s}",
 	    pv_display(sv,SvPVX_const(keyname), SvCUR(keyname), 0, 32));