From: Arran Cudbard-Bell <a.cudbardb@freeradius.org>
Date: Tue, 10 Dec 2019 08:16:26 +0000 (+0700)
Subject: Add notes on heap allocations
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d06a54dac90dc71d1291415eec24a140435f424b;p=thirdparty%2Ffreeradius-server.git

Add notes on heap allocations
---

diff --git a/src/lib/util/thread_local.h b/src/lib/util/thread_local.h
index 5fa309b6b84..0412e683ec6 100644
--- a/src/lib/util/thread_local.h
+++ b/src/lib/util/thread_local.h
@@ -49,8 +49,11 @@ typedef void (*pthread_destructor_t)(void*);
  *	These should ONLY be called where __Thread_local is a pointer to heap
  *	allocated memory that needs to be freed on thread exit.
  *
- *	For other types like ints _Thread_local should be used directly
- *	without the macros.
+ *	Depending on the platform, the thread local storage itself may be freed
+ *	before the destructor is called.
+ *
+ *	The only way this code can work is if the value passed to the destructor
+ *	initialisation is the address of non-TLS memory.
  */
 /** Pre-initialise resources required for a thread local destructor
  *