From f398eb67d321bfe2b4dd05cb57fa3c94a3337abc Mon Sep 17 00:00:00 2001
From: Nicholas Clark <nick@ccl4.org>
Date: Mon, 11 Apr 2005 14:53:38 +0000
Subject: [PATCH] Avoid taking a reference to SvIVX and putting that address on
 the save stack

p4raw-id: //depot/perl@24228
---
 perl.c   | 1 -
 pp_ctl.c | 7 ++++---
 pp_hot.c | 7 ++++---
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/perl.c b/perl.c
index 6d948e7..6967c8c 100644
--- a/perl.c
+++ b/perl.c
@@ -3906,7 +3906,6 @@ Perl_init_debugger(pTHX)
     PL_DBgv = gv_fetchpv("DB::DB", GV_ADDMULTI, SVt_PVGV);
     PL_DBline = gv_fetchpv("DB::dbline", GV_ADDMULTI, SVt_PVAV);
     PL_DBsub = gv_HVadd(gv_fetchpv("DB::sub", GV_ADDMULTI, SVt_PVHV));
-    sv_upgrade(GvSV(PL_DBsub), SVt_IV);	/* IVX accessed if PERLDB_SUB_NN */
     PL_DBsingle = GvSV((gv_fetchpv("DB::single", GV_ADDMULTI, SVt_PV)));
     sv_setiv(PL_DBsingle, 0);
     PL_DBtrace = GvSV((gv_fetchpv("DB::trace", GV_ADDMULTI, SVt_PV)));
diff --git a/pp_ctl.c b/pp_ctl.c
index 71634fb..933fb3f 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -2426,13 +2426,14 @@ PP(pp_goto)
 		    SV *sv = GvSV(PL_DBsub);
 		    CV *gotocv;
 
+		    save_item(sv);
 		    if (PERLDB_SUB_NN) {
-			(void)SvUPGRADE(sv, SVt_PVIV);
+			int type = SvTYPE(sv);
+			if (type < SVt_PVIV && type != SVt_IV)
+			    sv_upgrade(sv, SVt_PVIV);
 			(void)SvIOK_on(sv);
-			SAVEIV(SvIVX(sv));
 			SvIV_set(sv, PTR2IV(cv)); /* Do it the quickest way */
 		    } else {
-			save_item(sv);
 			gv_efullname3(sv, CvGV(cv), Nullch);
 		    }
 		    if (  PERLDB_GOTO
diff --git a/pp_hot.c b/pp_hot.c
index 85b42aa..b486586 100644
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -2560,10 +2560,10 @@ S_get_db_sub(pTHX_ SV **svp, CV *cv)
 {
     SV *dbsv = GvSV(PL_DBsub);
 
+    save_item(dbsv);
     if (!PERLDB_SUB_NN) {
 	GV *gv = CvGV(cv);
 
-	save_item(dbsv);
 	if ( (CvFLAGS(cv) & (CVf_ANON | CVf_CLONED))
 	     || strEQ(GvNAME(gv), "END")
 	     || ((GvCV(gv) != cv) && /* Could be imported, and old sub redefined. */
@@ -2580,9 +2580,10 @@ S_get_db_sub(pTHX_ SV **svp, CV *cv)
 	}
     }
     else {
-	(void)SvUPGRADE(dbsv, SVt_PVIV);
+	int type = SvTYPE(dbsv);
+	if (type < SVt_PVIV && type != SVt_IV)
+	    sv_upgrade(dbsv, SVt_PVIV);
 	(void)SvIOK_on(dbsv);
-	SAVEIV(SvIVX(dbsv));
 	SvIV_set(dbsv, PTR2IV(cv));	/* Do it the quickest way  */
     }
 
-- 
2.7.4