From 30f1fecc54cd9ca795c2ddfaca3fae6dc6edba2f Mon Sep 17 00:00:00 2001
From: Ryan Olson <ryanolsonk@gmail.com>
Date: Tue, 8 Sep 2015 10:48:58 -0600
Subject: [PATCH] Fix crash from trying to read isa fields as Class pointers on
 arm64

The isa field is not guaranteed to be a Class pointer on arm64, even though the type encoding indicates that it's a Class pointer.
---
 Classes/Utility/FLEXRuntimeUtility.m | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Classes/Utility/FLEXRuntimeUtility.m b/Classes/Utility/FLEXRuntimeUtility.m
index 6ebd4708e3..e67e6cc6c7 100644
--- a/Classes/Utility/FLEXRuntimeUtility.m
+++ b/Classes/Utility/FLEXRuntimeUtility.m
@@ -206,6 +206,13 @@ + (id)valueForIvar:(Ivar)ivar onObject:(id)object
 {
     id value = nil;
     const char *type = ivar_getTypeEncoding(ivar);
+#ifdef __arm64__
+    // See http://www.sealiesoftware.com/blog/archive/2013/09/24/objc_explain_Non-pointer_isa.html
+    const char *name = ivar_getName(ivar);
+    if (type[0] == @encode(Class)[0] && strcmp(name, "isa") != 0) {
+        value = object_getClass(object);
+    } else
+#endif
     if (type[0] == @encode(id)[0] || type[0] == @encode(Class)[0]) {
         value = object_getIvar(object, ivar);
     } else {