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    Subject[PATCH v2 11/16] media: sur40: Remove uninitialized_var() usage
    Date
    Using uninitialized_var() is dangerous as it papers over real bugs[1]
    (or can in the future), and suppresses unrelated compiler warnings (e.g.
    "unused variable"). If the compiler thinks it is uninitialized, either
    simply initialize the variable or make compiler changes. As a precursor
    to removing[2] this[3] macro[4], just remove this variable since it was
    actually unused:

    drivers/input/touchscreen/sur40.c:459:6: warning: variable 'packet_id' set but not used [-Wunused-but-set-variable]
    459 | u32 packet_id;
    | ^~~~~~~~~

    However, in keeping with the documentation desires outlined in commit
    335abaea7a27 ("Input: sur40 - silence unnecessary noisy debug output"),
    comment out the assignment instead of removing it.

    [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
    [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
    [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
    [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

    Fixes: 335abaea7a27 ("Input: sur40 - silence unnecessary noisy debug output")
    Signed-off-by: Kees Cook <keescook@chromium.org>
    ---
    drivers/input/touchscreen/sur40.c | 4 +---
    1 file changed, 1 insertion(+), 3 deletions(-)

    diff --git a/drivers/input/touchscreen/sur40.c b/drivers/input/touchscreen/sur40.c
    index 34d31c7ec8ba..620cdd7d214a 100644
    --- a/drivers/input/touchscreen/sur40.c
    +++ b/drivers/input/touchscreen/sur40.c
    @@ -456,8 +456,6 @@ static void sur40_poll(struct input_dev *input)
    {
    struct sur40_state *sur40 = input_get_drvdata(input);
    int result, bulk_read, need_blobs, packet_blobs, i;
    - u32 uninitialized_var(packet_id);
    -
    struct sur40_header *header = &sur40->bulk_in_buffer->header;
    struct sur40_blob *inblob = &sur40->bulk_in_buffer->blobs[0];

    @@ -491,7 +489,7 @@ static void sur40_poll(struct input_dev *input)
    if (need_blobs == -1) {
    need_blobs = le16_to_cpu(header->count);
    dev_dbg(sur40->dev, "need %d blobs\n", need_blobs);
    - packet_id = le32_to_cpu(header->packet_id);
    + /* packet_id = le32_to_cpu(header->packet_id); */
    }

    /*
    --
    2.25.1
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