From fb9c0d7e317d1320c130ef7a5906f8f2660d5644 Mon Sep 17 00:00:00 2001
From: Evan Cheng <evan.cheng@apple.com>
Date: Fri, 1 Sep 2006 07:09:56 +0000
Subject: [PATCH] Better comments.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30017 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/ExecutionEngine/JIT/JIT.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/ExecutionEngine/JIT/JIT.cpp b/lib/ExecutionEngine/JIT/JIT.cpp
index f7f86d7e61a..919f9af002b 100644
--- a/lib/ExecutionEngine/JIT/JIT.cpp
+++ b/lib/ExecutionEngine/JIT/JIT.cpp
@@ -312,7 +312,10 @@ void *JIT::getOrEmitGlobalVariable(const GlobalVariable *GV) {
 #ifdef __APPLE__
 #if MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_4 && \
     __APPLE_CC__ >= 5330
-    // __dso_handle is resolved by the Mac OS X dynamic linker.
+    // Apple gcc defaults to -fuse-cxa-atexit (i.e. calls __cxa_atexit instead
+    // of atexit). It passes the address of linker generated symbol __dso_handle
+    // to the function.
+    // This configuration change happened at version 5330.
     if (GV->getName() == "__dso_handle")
       return (void*)&__dso_handle;
 #endif