From: Nick Ing-Simmons <nik@tiuk.ti.com>
Date: Thu, 2 May 2002 07:54:51 +0000 (+0000)
Subject: Fix the "PerlIO require leak". Snag was that clean_objs
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=9f4bd2225c152364d8589911c4c769edae165d9b;p=p5sagit%2Fp5-mst-13.2.git

Fix the "PerlIO require leak". Snag was that clean_objs
autoloaded DESTROY (needing IO) after known layers had
been freed. Postpone layer list free to PerlIO_cleanup,
rather than PerlIO_destruct. Tweak sequence in perl_destruct
so that sv_undef is immortal till layer list is done with it.

p4raw-id: //depot/perlio@16335
---

diff --git a/perl.c b/perl.c
index 7b6eb62..7164d55 100644
--- a/perl.c
+++ b/perl.c
@@ -431,7 +431,7 @@ perl_destruct(pTHXx)
     FREETMPS;
 
     /* Need to flush since END blocks can produce output */
-    PerlIO_flush((PerlIO*)NULL); 
+    PerlIO_flush((PerlIO*)NULL);
 
     if (CALL_FPTR(PL_threadhook)(aTHX)) {
         /* Threads hook has vetoed further cleanup */
@@ -825,9 +825,6 @@ perl_destruct(pTHXx)
     SvANY(&PL_sv_no) = NULL;
     SvFLAGS(&PL_sv_no) = 0;
 
-    SvREFCNT(&PL_sv_undef) = 0;
-    SvREADONLY_off(&PL_sv_undef);
-
     {
         int i;
         for (i=0; i<=2; i++) {
@@ -846,6 +843,13 @@ perl_destruct(pTHXx)
     PerlIO_cleanup(aTHX);
 #endif
 
+    /* sv_undef needs to stay immortal until after PerlIO_cleanup
+       as currently layers use it rather than Nullsv as a marker
+       for no arg - and will try and SvREFCNT_dec it.
+     */
+    SvREFCNT(&PL_sv_undef) = 0;
+    SvREADONLY_off(&PL_sv_undef);
+
     Safefree(PL_origfilename);
     Safefree(PL_reg_start_tmp);
     if (PL_reg_curpm)
diff --git a/perlio.c b/perlio.c
index ac35527..e80c1f0 100644
--- a/perlio.c
+++ b/perlio.c
@@ -601,10 +601,6 @@ PerlIO_destruct(pTHX)
 	    f++;
 	}
     }
-    PerlIO_list_free(aTHX_ PL_known_layers);
-    PL_known_layers = NULL;
-    PerlIO_list_free(aTHX_ PL_def_layerlist);
-    PL_def_layerlist = NULL;
 }
 
 void
@@ -2071,7 +2067,9 @@ PerlIO_cleanup(pTHX)
 {
     int i;
 #ifdef USE_ITHREADS
-    PerlIO_debug("Cleanup %p\n",aTHX);
+    PerlIO_debug("Cleanup layers for %p\n",aTHX);
+#else
+    PerlIO_debug("Cleanup layers\n");
 #endif
     /* Raise STDIN..STDERR refcount so we don't close them */
     for (i=0; i < 3; i++)
@@ -2080,6 +2078,15 @@ PerlIO_cleanup(pTHX)
     /* Restore STDIN..STDERR refcount */
     for (i=0; i < 3; i++)
 	PerlIOUnix_refcnt_dec(i);
+
+    if (PL_known_layers) {
+	PerlIO_list_free(aTHX_ PL_known_layers);
+	PL_known_layers = NULL;
+    }
+    if(PL_def_layerlist) {
+	PerlIO_list_free(aTHX_ PL_def_layerlist);
+	PL_def_layerlist = NULL;
+    }
 }