Index: Python/thread_pthread.h
===================================================================
--- Python/thread_pthread.h	(revision 85743)
+++ Python/thread_pthread.h	(working copy)
@@ -18,6 +18,18 @@
 #ifndef THREAD_STACK_SIZE
 #define THREAD_STACK_SIZE       0       /* use default stack size */
 #endif
+
+#if defined(__APPLE__) && defined(THREAD_STACK_SIZE) && THREAD_STACK_SIZE == 0
+   /* The default stack size for new threads on OSX is small enough that
+    * we'll get hard crashes instead of 'maximum recursion depth exceeded'
+    * exceptions.
+    *
+    * The default stack size below is the minimal stack size where a
+    * simple recursive function doesn't cause a hard crash.
+    */
+#undef  THREAD_STACK_SIZE
+#define THREAD_STACK_SIZE 	0xb0000
+#endif
 /* for safety, ensure a viable minimum stacksize */
 #define THREAD_STACK_MIN        0x8000  /* 32kB */
 #else  /* !_POSIX_THREAD_ATTR_STACKSIZE */