See the below code snippet:

while(l_counter != 0)
{
    int mod = l_counter % LOCAL_TOTAL;
    int pix_per_thr = l_counter / LOCAL_TOTAL + ((lid < mod) ? 1 : 0);

    for (int i = 0; i < pix_per_thr; ++i)
    {
        int index = atomic_dec(&l_counter) - 1;
        ....
    }
    ....
    barrier(CLK_LOCAL_MEM_FENCE);
}

If we don't put a barrier before the for loop, then there is a possiblity
that some work item enter this loop but the others are not, the the l_counter
will be reduced in the for loop and may be changed to zero, and the other
work items may can't enter the while loop. If this happens, it breaks the
barrier's rule which requires all the work items reach the same barrier.
And it may hang the GPU depends on the implementation of opencl platform.

This issue is raised at:
https://github.com/Itseez/opencv/issues/5175Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>

fixed incorrect behaviour of move semantics for cv::Ptr, cv::Mat, cv::UMat in case when rvalue-reference references to *this.

responses must be float, else we trigger an assertion in line 150

add a cast to double, to make vs compilers happy

typo correction

This reverts part of commit 0db10a30

cosmetic changes to fix this warning.
real bugs not found