From: Nicholas Clark <nick@ccl4.org>
Date: Sat, 7 May 2011 10:23:01 +0000 (+0200)
Subject: Magic vtables aren't freed when magic is freed, so don't count them.
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=9847261df894191f35b2917704fb21809f8609b7;p=p5sagit%2FDevel-Size.git

Magic vtables aren't freed when magic is freed, so don't count them.

They are static structures. Anything that assumes otherwise is buggy.
---

diff --git a/CHANGES b/CHANGES
index f221c7f..e91a6b9 100644
--- a/CHANGES
+++ b/CHANGES
@@ -3,6 +3,8 @@ Revision history for Perl extension Devel::Size.
 0.72_52 2011-05-09 nicholas
  * Use a table for SV body sizes. These incorporate the space saving post 5.8.x
  * Correctly handle SvOOK scalars. 5.12 and later don't use SvIVX().
+ * Magic vtables aren't freed when magic is freed, so don't count them.
+   (They are static structures. Anything that assumes otherwise is buggy.)
 
 0.75_51 2011-05-05 nicholas
  * Only use a static array of vtables on gcc.
diff --git a/Makefile.PL b/Makefile.PL
index 2f91101..e2dce20 100644
--- a/Makefile.PL
+++ b/Makefile.PL
@@ -8,43 +8,10 @@ use Config;
     or die "Your pointer size of $Config{ptrsize} is very confusing";
 my $ptr_bits = length $1;
 
-my $svh = "$Config{archlibexp}/CORE/perl.h";
-my $vtable_file = 'vtables.inc';
-
-my %vtables;
-open FH, "<$svh"
-    or die "Can't open $svh ($!) - is your perl install missing its headers?";
-while (<FH>) {
-    next unless /^\s+(PL_vtbl_[a-z]+),\s*$/ or /^EXT MGVTBL (PL_vtbl_[a-z]+) =/;
-    ++$vtables{$1};
-}
-warn "Didn't find any vtable names in $svh" unless %vtables;
-close FH;
-
-
-my %special = (
-	       PL_vtbl_collxfrm => 'USE_LOCALE_COLLATE',
-	       PL_vtbl_mutex => 'USE_5005THREADS',
-);
-
-open FH, ">$vtable_file" or die "Can't open $vtable_file: $!";
-foreach (sort keys %vtables) {
-    print FH "#ifdef $special{$_}\n" if ($special{$_});
-    if ($Config{gccversion}) {
-	print FH "    &$_,\n";
-    } else {
-	print FH "    check_new(st, &$_);\n";
-    }
-    print FH "#endif\n" if ($special{$_});
-}
-
-close FH or die "Error closing $vtable_file: $!";
-
 WriteMakefile(
 	      NAME => 'Devel::Size',
 	      VERSION_FROM => 'lib/Devel/Size.pm',
 	      DEFINE => "-DALIGN_BITS=$ptr_bits",
 	      (eval $ExtUtils::MakeMaker::VERSION >= 6.47 ? (MIN_PERL_VERSION => '5.008') : ()),
 	      (eval $ExtUtils::MakeMaker::VERSION >= 6.31 ? (LICENSE => 'perl') : ()),
-	      realclean => {FILES=> $vtable_file},
 );
diff --git a/Size.xs b/Size.xs
index 913467b..fa0673f 100644
--- a/Size.xs
+++ b/Size.xs
@@ -315,12 +315,12 @@ magic_size(pTHX_ const SV * const thing, struct state *st) {
   /* Have we seen the magic pointer?  (NULL has always been seen before)  */
   while (check_new(st, magic_pointer)) {
     st->total_size += sizeof(MAGIC);
+    /* magic vtables aren't freed when magic is freed, so don't count them.
+       (They are static structures. Anything that assumes otherwise is buggy.)
+    */
+
 
     TRY_TO_CATCH_SEGV {
-        /* Have we seen the magic vtable? */
-        if (check_new(st, magic_pointer->mg_virtual)) {
-          st->total_size += sizeof(MGVTBL);
-        }
 	sv_size(aTHX_ st, magic_pointer->mg_obj, TOTAL_SIZE_RECURSION);
 	if (magic_pointer->mg_len == HEf_SVKEY) {
 	    sv_size(aTHX_ st, (SV *)magic_pointer->mg_ptr, TOTAL_SIZE_RECURSION);
@@ -773,27 +773,11 @@ sv_size(pTHX_ struct state *const st, const SV * const orig_thing,
   return TRUE;
 }
 
-/* Frustratingly, the vtables aren't const in perl.h
-   gcc is happy enough to have non-const initialisers in a static array.
-   VC seems not to be. (Is it actually treating the file as C++?)
-   So do the maximally portable thing, unless we know it's gcc, in which case
-   we can do the more space efficient version.  */
-
-#if __GNUC__
-void *vtables[] = {
-#include "vtables.inc"
-    NULL
-};
-#endif
-
 static struct state *
 new_state(pTHX)
 {
     SV *warn_flag;
     struct state *st;
-#if __GNUC__
-    void **vt_p = vtables;
-#endif
 
     Newxz(st, 1, struct state);
     st->go_yell = TRUE;
@@ -806,12 +790,6 @@ new_state(pTHX)
     check_new(st, &PL_sv_undef);
     check_new(st, &PL_sv_no);
     check_new(st, &PL_sv_yes);
-#if __GNUC__
-    while(*vt_p)
-	check_new(st, *vt_p++);
-#else
-#include "vtables.inc"
-#endif
     return st;
 }