range operator does magical string increment iff both operands

are non-numbers, from Tom Phoenix <rootbeer@redcat.com>; fixed
the "foreach (RANGE)" case as well

p4raw-id: //depot/perl@4730

2 files changed, 18 insertions, 3 deletions

diff --git a/pp_ctl.c b/pp_ctl.c
index c028b4eca5..34e18b5f32 100644
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -997,7 +997,9 @@ PP(pp_flop)
 	    mg_get(right);
 
 	if (SvNIOKp(left) || !SvPOKp(left) ||
-	  (looks_like_number(left) && *SvPVX(left) != '0') )
+	    SvNIOKp(right) || !SvPOKp(right) ||
+	    (looks_like_number(left) && *SvPVX(left) != '0' &&
+	     looks_like_number(right) && *SvPVX(right) != '0'))
 	{
 	    if (SvNV(left) < IV_MIN || SvNV(right) > IV_MAX)
 		DIE(aTHX_ "Range iterator outside integer range");
@@ -1674,7 +1676,11 @@ PP(pp_enteriter)
 	if (SvTYPE(cx->blk_loop.iterary) != SVt_PVAV) {
 	    dPOPss;
 	    if (SvNIOKp(sv) || !SvPOKp(sv) ||
-		(looks_like_number(sv) && *SvPVX(sv) != '0')) {
+		SvNIOKp(cx->blk_loop.iterary) || !SvPOKp(cx->blk_loop.iterary) ||
+		(looks_like_number(sv) && *SvPVX(sv) != '0' &&
+		 looks_like_number((SV*)cx->blk_loop.iterary) &&
+		 *SvPVX(cx->blk_loop.iterary) != '0'))
+	    {
 		 if (SvNV(sv) < IV_MIN ||
 		     SvNV((SV*)cx->blk_loop.iterary) >= IV_MAX)
 		     DIE(aTHX_ "Range iterator outside integer range");
diff --git a/t/op/range.t b/t/op/range.t
index 1698db4a55..e8aecf5fc9 100755
--- a/t/op/range.t
+++ b/t/op/range.t
@@ -1,6 +1,6 @@
 #!./perl
 
-print "1..13\n";
+print "1..15\n";
 
 print join(':',1..5) eq '1:2:3:4:5' ? "ok 1\n" : "not ok 1\n";
 
@@ -64,3 +64,12 @@ print "ok 12\n";
     $bad = 1 unless $x eq 'a:b:c:d:e';
     print $bad ? "not ok 13\n" : "ok 13\n";
 }
+
+# Should use magical autoinc only when both are strings
+print "not " unless 0 == (() = "0"..-1);
+print "ok 14\n";
+
+for my $x ("0"..-1) {
+    print "not ";
+}
+print "ok 15\n";