fixed issue 83: Added Internals::hv_clear_placeholders XS name exception

similar
to version::, see universal.c:struct xsub_details details[]

Changes

@@ -14,6 +14,8 @@
 	New debug option -Dr "runtime" to add debug output to the .c code (as in CC)
 	New option -Upackage to skip package, mark_skip()
 	Re-implemented sharepvn via share_hek() and SvLEN=0 (71)
+	Added Internals::hv_clear_placeholders XS name exception, similar
+	  to version:: (issue 83)
 	* CC (1.12) allow overriding of -f<opt> B::C flags
 	* perlcc (2.13): added options -O1-4, -u, -U, --Wc, --Wl, --version,
 	Keep cfile if output is empty,

lib/B/C.pm

@@ -2420,7 +2420,7 @@ sub B::CV::save {
       my $xsstash = $stashname;
       $xsstash =~ s/::/_/g;
       my $xs = "XS_${xsstash}_${cvname}";
-      if ($stashname eq 'version') {
+      if ($stashname eq 'version') { # exceptions see universal.c:struct xsub_details details[]
         my %vtrans = ('()'   => 'noop',
                       'parse' => 'new',
                       '(""'   => 'stringify',
@@ -2435,6 +2435,9 @@ sub B::CV::save {
           $xs = "XS_${xsstash}_".$vtrans{$cvname};
         }
       }
+      if ($fullname eq 'Internals::hv_clear_placeholders') {
+	$xs = 'XS_Internals_hv_clear_placehold';
+      }
       warn sprintf( "core XSUB $xs CV 0x%x\n", $$cv )
     	if $debug{cv};
       if (!$ENV{DL_NOWARN} and $stashname eq 'DynaLoader' and $] >= 5.015002 and $] < 5.015004) {
@@ -4636,7 +4639,7 @@ sub add_hashINC {
         if (-e $p) { $INC{$incpack} = $p; last; }
       }
       $INC{$incpack} = $incpack unless $INC{$incpack};
-    } 
+    }
   }
 }