@@ -2940,20 +2940,29 @@ pointer_to_safe_refcount(void *ptr)
 {
     uintptr_t full = (uintptr_t)ptr;
     assert((full & 3) == 0);
+#if SIZEOF_VOID_P > 4
     uint32_t refcnt = (uint32_t)full;
     if (refcnt >= (uint32_t)_Py_IMMORTAL_MINIMUM_REFCNT) {
         full = full - ((uintptr_t)_Py_IMMORTAL_MINIMUM_REFCNT) + 1;
     }
     return full + 2;
+#else
+    // Make the top two bits 0, so it appears mortal.
+    return (full >> 2) + 1;
+#endif
 }
 
 static void *
 safe_refcount_to_pointer(uintptr_t refcnt)
 {
+#if SIZEOF_VOID_P > 4
     if (refcnt & 1) {
         refcnt += _Py_IMMORTAL_MINIMUM_REFCNT - 1;
     }
     return (void *)(refcnt - 2);
+#else
+    return (void *)((refcnt -1) << 2);
+#endif
 }
 #endif
Original file line number	Diff line number	Diff line change
`@@ -2940,20 +2940,29 @@ pointer_to_safe_refcount(void *ptr)`
`2940`	`2940`	`{`
`2941`	`2941`	`uintptr_t full = (uintptr_t)ptr;`
`2942`	`2942`	`assert((full & 3) == 0);`
	`2943`	`+#if SIZEOF_VOID_P > 4`
`2943`	`2944`	`uint32_t refcnt = (uint32_t)full;`
`2944`	`2945`	`if (refcnt >= (uint32_t)_Py_IMMORTAL_MINIMUM_REFCNT) {`
`2945`	`2946`	`full = full - ((uintptr_t)_Py_IMMORTAL_MINIMUM_REFCNT) + 1;`
`2946`	`2947`	`}`
`2947`	`2948`	`return full + 2;`
	`2949`	`+#else`
	`2950`	`+ // Make the top two bits 0, so it appears mortal.`
	`2951`	`+ return (full >> 2) + 1;`
	`2952`	`+#endif`
`2948`	`2953`	`}`
`2949`	`2954`
`2950`	`2955`	`static void *`
`2951`	`2956`	`safe_refcount_to_pointer(uintptr_t refcnt)`
`2952`	`2957`	`{`
	`2958`	`+#if SIZEOF_VOID_P > 4`
`2953`	`2959`	`if (refcnt & 1) {`
`2954`	`2960`	`refcnt += _Py_IMMORTAL_MINIMUM_REFCNT - 1;`
`2955`	`2961`	`}`
`2956`	`2962`	`return (void *)(refcnt - 2);`
	`2963`	`+#else`
	`2964`	`+ return (void *)((refcnt -1) << 2);`
	`2965`	`+#endif`
`2957`	`2966`	`}`
`2958`	`2967`	`#endif`
`2959`	`2968`