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From 15c7c4d39b317f0d902ef28fd43eca5c3369f891 Mon Sep 17 00:00:00 2001
From: Max Filippov <jcmvbkbc@gmail.com>
Date: Sat, 15 Aug 2015 05:12:11 +0300
Subject: [PATCH 3/3] xtensa: fix _Unwind_GetCFA

Returning context->cfa in _Unwind_GetCFA makes CFA point one stack frame
higher than what was actually used by code at context->ra. This results
in invalid CFA value in signal frames and premature unwinding completion
in forced unwinding used by uClibc NPTL thread cancellation.
Returning context->sp from _Unwind_GetCFA makes all CFA values valid and
matching code that used them.

2015-08-18  Max Filippov  <jcmvbkbc@gmail.com>
libgcc/
	* config/xtensa/unwind-dw2-xtensa.c (_Unwind_GetCFA): Return
	context->sp instead of context->cfa.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
---
Backported from: r226964

 libgcc/config/xtensa/unwind-dw2-xtensa.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libgcc/config/xtensa/unwind-dw2-xtensa.c b/libgcc/config/xtensa/unwind-dw2-xtensa.c
index 35f7797..ef6b900 100644
--- a/libgcc/config/xtensa/unwind-dw2-xtensa.c
+++ b/libgcc/config/xtensa/unwind-dw2-xtensa.c
@@ -130,7 +130,7 @@ _Unwind_GetGR (struct _Unwind_Context *context, int index)
 _Unwind_Word
 _Unwind_GetCFA (struct _Unwind_Context *context)
 {
-  return (_Unwind_Ptr) context->cfa;
+  return (_Unwind_Ptr) context->sp;
 }
 
 /* Overwrite the saved value for register INDEX in CONTEXT with VAL.  */
-- 
1.8.1.4