// we have too few registers available. In my tests it was worth
// about 5% in GC performance, but of course that might change as gcc
// improves. -- SDM 2009/04/03
+//
+// We ought to do the same on MacOS X, but __thread is not
+// supported there yet (gcc 4.0.1).
extern __thread gc_thread* gct;
#define DECLARE_GCT __thread gc_thread* gct;