Memory leak after thread exit, fixed (alloc cache released by exit), belong to ticket [3493120]

Moved over to branch bug-3493120.  This is not ready
for the core-8-5-branch.  Segfaults all over the place
in a thread-enabled build on a CentOS system.

3 files changed, 34 insertions, 2 deletions

diff --git a/generic/tclInt.h b/generic/tclInt.h
index 1348340..00b246b 100644
--- a/generic/tclInt.h
+++ b/generic/tclInt.h
@@ -2550,6 +2550,7 @@ MODULE_SCOPE void	TclFinalizeObjects(void);
 MODULE_SCOPE void	TclFinalizePreserve(void);
 MODULE_SCOPE void	TclFinalizeSynchronization(void);
 MODULE_SCOPE void	TclFinalizeThreadAlloc(void);
+MODULE_SCOPE void	TclFinalizeThreadAllocThread(void);
 MODULE_SCOPE void	TclFinalizeThreadData(void);
 MODULE_SCOPE void	TclFinalizeThreadObjects(void);
 MODULE_SCOPE double	TclFloor(mp_int *a);
diff --git a/generic/tclThread.c b/generic/tclThread.c
index 8384107..d6b5bcb 100644
--- a/generic/tclThread.c
+++ b/generic/tclThread.c
@@ -338,8 +338,9 @@ Tcl_ConditionFinalize(
  *
  * TclFinalizeThreadData --
  *
- *	This function cleans up the thread-local storage. This is called once
- *	for each thread.
+ *	This function cleans up the thread-local storage. Secondary, it cleans
+ *	thread alloc cache.
+ *	This is called once for each thread before thread exits.
  *
  * Results:
  *	None.
@@ -354,6 +355,9 @@ void
 TclFinalizeThreadData(void)
 {
     TclpFinalizeThreadDataThread();
+#if defined(TCL_THREADS) && defined(USE_THREAD_ALLOC)
+    TclFinalizeThreadAllocThread();
+#endif
 }
 
 /*
diff --git a/generic/tclThreadAlloc.c b/generic/tclThreadAlloc.c
index 2e74fa7..106e908 100644
--- a/generic/tclThreadAlloc.c
+++ b/generic/tclThreadAlloc.c
@@ -1012,6 +1012,33 @@ TclFinalizeThreadAlloc(void)
     TclpFreeAllocCache(NULL);
 }
 
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclFinalizeThreadAllocThread --
+ *
+ *	This procedure is used to destroy single thread private resources used
+ *	in this file. 
+ * Called in TclpFinalizeThreadData when a thread exits (Tcl_FinalizeThread).
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclFinalizeThreadAllocThread(void)
+{
+    Cache *cachePtr = TclpGetAllocCache();
+    if (cachePtr != NULL) {
+	TclpFreeAllocCache(cachePtr);
+    }
+}
+
 #else /* !(TCL_THREADS && USE_THREAD_ALLOC) */
 /*
  *----------------------------------------------------------------------