=== modified file 'src/libCom/osi/epicsThread.cpp'
--- src/libCom/osi/epicsThread.cpp	2011-01-15 01:01:53 +0000
+++ src/libCom/osi/epicsThread.cpp	2016-03-16 23:15:14 +0000
@@ -78,36 +78,37 @@
 {
     epicsThread * pThread = 
         static_cast <epicsThread *> ( pPvt );
-    bool waitRelease = false;
+    bool threadDestroyed = false;
     try {
-        pThread->pWaitReleaseFlag = & waitRelease;
+        pThread->pThreadDestroyed = & threadDestroyed;
         if ( pThread->beginWait () ) {
             pThread->runable.run ();
-            // current thread may have run the destructor 
-            // so must not touch the this pointer from
-            // here on down if waitRelease is true
+            // The run() routine may have destroyed the epicsThread
+            // object by now; pThread can only be used below here
+            // when the threadDestroyed flag is false.
         }
     }
     catch ( const epicsThread::exitException & ) {
     }
     catch ( std::exception & except ) {
-        if ( ! waitRelease ) {
-            pThread->printLastChanceExceptionMessage ( 
+        if ( ! threadDestroyed ) {
+            pThread->printLastChanceExceptionMessage (
                 typeid ( except ).name (), except.what () );
         }
     }
     catch ( ... ) {
-        if ( ! waitRelease ) {
-            pThread->printLastChanceExceptionMessage ( 
+        if ( ! threadDestroyed ) {
+            pThread->printLastChanceExceptionMessage (
                 "catch ( ... )", "Non-standard C++ exception" );
         }
     }
-    if ( ! waitRelease ) {
+    if ( ! threadDestroyed ) {
         epicsGuard < epicsMutex > guard ( pThread->mutex );
+        pThread->pThreadDestroyed = NULL;
         pThread->terminated = true;
         pThread->exitEvent.signal ();
-        // once the terminated flag is set and we release the lock
-        // then the "this" pointer must not be touched again
+        // After the terminated flag is set and guard's destructor
+        // releases the lock, pThread must never be used again.
     }
 }
 
@@ -135,12 +136,12 @@
 bool epicsThread::exitWait ( const double delay ) throw ()
 {
     try {
-        // if destructor is running in managed thread then of 
-        // course we will not wait for the managed thread to 
-        // exit
+        // When called (usually by a destructor) in the context of
+        // the managed thread we can't wait for the thread to exit.
+        // Set the threadDestroyed flag and return success.
         if ( this->isCurrentThread() ) {
-            if ( this->pWaitReleaseFlag ) {
-                *this->pWaitReleaseFlag = true;
+            if ( this->pThreadDestroyed ) {
+                *this->pThreadDestroyed = true;
             }
             return true;
         }
@@ -177,7 +178,7 @@
 epicsThread::epicsThread ( 
     epicsThreadRunable & runableIn, const char * pName,
         unsigned stackSize, unsigned priority ) :
-    runable ( runableIn ), id ( 0 ), pWaitReleaseFlag ( 0 ),
+    runable ( runableIn ), id ( 0 ), pThreadDestroyed ( 0 ),
     begin ( false ), cancel ( false ), terminated ( false )
 {
     this->id = epicsThreadCreate ( 
@@ -303,7 +304,7 @@
     if ( level > 0u ) {
         epicsThreadShow ( this->id, level - 1 );
         if ( level > 1u ) {
-            ::printf ( "pWaitReleaseFlag = %p\n", this->pWaitReleaseFlag );
+            ::printf ( "pThreadDestroyed = %p\n", this->pThreadDestroyed );
             ::printf ( "begin = %c, cancel = %c, terminated = %c\n",
                 this->begin ? 'T' : 'F',
                 this->cancel ? 'T' : 'F',

=== modified file 'src/libCom/osi/epicsThread.h'
--- src/libCom/osi/epicsThread.h	2010-04-26 20:38:11 +0000
+++ src/libCom/osi/epicsThread.h	2016-03-16 23:15:14 +0000
@@ -160,7 +160,7 @@
     epicsMutex mutex;
     epicsEvent event;
     epicsEvent exitEvent;
-    bool * pWaitReleaseFlag;
+    bool * pThreadDestroyed;
     bool begin;
     bool cancel;
     bool terminated;