From 8339a2d441772e8d4d7dd6d4e00d2eccf9cb8cbe Mon Sep 17 00:00:00 2001
From: Jason Turner <jason@emptycrate.com>
Date: Wed, 4 Jun 2014 14:11:18 -0600
Subject: [PATCH] Fix shared data problem on MacOS 10.9 with xcode 5.1

Move to construct on first use idiom for singleton definition,
which prevents problems with singletons between ruby swig modules
in an environment with multiple modules on MacOS 10.9 with xcode 5.1.

Before this fix, data was being shared between modules which caused
a crash on shutdown of the ruby interpreter if more than one
module was loaded at a time.
---
 Lib/ruby/rubyclasses.swg | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/Lib/ruby/rubyclasses.swg b/Lib/ruby/rubyclasses.swg
index 5537136af..f7b51bdcc 100644
--- a/Lib/ruby/rubyclasses.swg
+++ b/Lib/ruby/rubyclasses.swg
@@ -37,9 +37,6 @@
 %fragment("GC_VALUE_definition","header") {
 namespace swig {
   class SwigGCReferences {
-    // Hash of all GC_VALUE's currently in use
-    static SwigGCReferences s_references;
-
     VALUE _hash;
 
     SwigGCReferences() : _hash(Qnil) {
@@ -50,13 +47,18 @@ namespace swig {
     }
     static void EndProcHandler(VALUE) {
       // Ruby interpreter ending - _hash can no longer be accessed.
+      SwigGCReferences &s_references = instance();
       s_references._hash = Qnil;
     }
   public:
     static SwigGCReferences& instance() {
+      // Hash of all GC_VALUE's currently in use
+      static SwigGCReferences s_references;
+
       return s_references;
     }
     static void initialize() {
+      SwigGCReferences &s_references = instance();
       if (s_references._hash == Qnil) {
         rb_set_end_proc(&EndProcHandler, Qnil);
         s_references._hash = rb_hash_new();
@@ -81,13 +83,13 @@ namespace swig {
       if (BUILTIN_TYPE(obj) == T_NONE)
         return;
       if (_hash != Qnil) {
-        VALUE val = rb_hash_aref(s_references._hash, obj);
+        VALUE val = rb_hash_aref(_hash, obj);
         unsigned n = FIXNUM_P(val) ? NUM2UINT(val) : 1;
         --n;
         if (n)
-          rb_hash_aset(s_references._hash, obj, INT2NUM(n));
+          rb_hash_aset(_hash, obj, INT2NUM(n));
         else
-          rb_hash_delete(s_references._hash, obj);
+          rb_hash_delete(_hash, obj);
       }
     }
   };
@@ -302,8 +304,6 @@ namespace swig {
   ID  GC_VALUE::lshift_id = rb_intern("<<");
   ID  GC_VALUE::rshift_id = rb_intern(">>");
 
-  SwigGCReferences SwigGCReferences::s_references;
-
   typedef GC_VALUE LANGUAGE_OBJ;
 
 } // namespace swig