formline() could wipe out readonly-ness, freeing constants

prematurely, or affect cloning of pad constants

p4raw-id: //depot/perl@5056

diff --git a/pp_ctl.c b/pp_ctl.c
index 972c21d..7b4cbfe 100644 (file)
--- a/pp_ctl.c
+++ b/pp_ctl.c
@@ -302,8 +302,13 @@ PP(pp_formline)
     bool item_is_utf = FALSE;
 
     if (!SvMAGICAL(tmpForm) || !SvCOMPILED(tmpForm)) {
-       SvREADONLY_off(tmpForm);
-       doparseform(tmpForm);
+       if (SvREADONLY(tmpForm)) {
+           SvREADONLY_off(tmpForm);
+           doparseform(tmpForm);
+           SvREADONLY_on(tmpForm);
+       }
+       else
+           doparseform(tmpForm);
     }
 
     SvPV_force(PL_formtarget, len);

diff --git a/t/op/write.t b/t/op/write.t
index 9918b2f..87d5042 100755 (executable)
--- a/t/op/write.t
+++ b/t/op/write.t
@@ -1,8 +1,6 @@
 #!./perl
 
-# $RCSfile: write.t,v $$Revision: 4.1 $$Date: 92/08/07 18:28:38 $
-
-print "1..6\n";
+print "1..8\n";
 
 my $CAT = ($^O eq 'MSWin32') ? 'type' : 'cat';
 
@@ -190,3 +188,16 @@ if (`$CAT Op_write.tmp` eq $right)
 else
     { print "not ok 6\n"; }
 
+# test lexicals and globals
+{
+    my $this = "ok";
+    our $that = 7;
+    format LEX =
+@<<@|
+$this,$that
+.
+    open(LEX, ">&STDOUT") or die;
+    write LEX;
+    $that = 8;
+    write LEX;
+}