diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 8dbb3bd7..3556a7b6 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -29,7 +29,11 @@
 end
 
 if GC.respond_to?(:auto_compact=)
-  GC.auto_compact = true
+  begin
+    GC.auto_compact = true
+  rescue NotImplementedError
+    # Some platforms don't support compaction
+  end
 end
 
 IS_JRUBY = RUBY_ENGINE == 'jruby'