From 7fd21d217ad7cc027f5cdd3474b17df71343ba2a Mon Sep 17 00:00:00 2001
From: Vladislav Vinogradov <vlad.vinogradov@itseez.com>
Date: Thu, 20 Feb 2014 10:24:52 +0400
Subject: [PATCH] fix bug #3562:

add missing __syncthreads to edgesHysteresisLocalKernel
---
 modules/gpu/src/cuda/canny.cu | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/modules/gpu/src/cuda/canny.cu b/modules/gpu/src/cuda/canny.cu
index 1dc179e34..468eec417 100644
--- a/modules/gpu/src/cuda/canny.cu
+++ b/modules/gpu/src/cuda/canny.cu
@@ -293,8 +293,12 @@ namespace canny
                 n += smem[threadIdx.y + 2][threadIdx.x + 2] == 2;
             }
 
+            __syncthreads();
+
             if (n > 0)
                 smem[threadIdx.y + 1][threadIdx.x + 1] = 2;
+
+            __syncthreads();
         }
 
         const int e = smem[threadIdx.y + 1][threadIdx.x + 1];