On Fri, Mar 22, 2019 at 03:18:43PM +0100, Arnd Bergmann wrote:
> clang produces a false-positive warning as it fails to notice
> that "lost = true" implies that "ret" is initialized:
>
> net/rxrpc/output.c:402:6: error: variable 'ret' is used uninitialized
> whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
> if (lost)
> ^~~~
> net/rxrpc/output.c:437:6: note: uninitialized use occurs here
> if (ret >= 0) {
> ^~~
> net/rxrpc/output.c:402:2: note: remove the 'if' if its condition is always
> false
> if (lost)
> ^~~~~~~~~
> net/rxrpc/output.c:339:9: note: initialize the variable 'ret' to silence this
> warning
> int ret, opt;
> ^
> = 0
>
> Rearrange the code to make that more obvious and avoid the warning.
>
> Signed-off-by: Arnd Bergmann <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>
> ---
> net/rxrpc/output.c | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
> index 736aa9281100..004c762c2e8d 100644
> --- a/net/rxrpc/output.c
> +++ b/net/rxrpc/output.c
> @@ -335,7 +335,6 @@ int rxrpc_send_data_packet(struct rxrpc_call *call,
> struct sk_buff *skb,
> struct kvec iov[2];
> rxrpc_serial_t serial;
> size_t len;
> - bool lost = false;
> int ret, opt;
>
> _enter(",{%d}", skb->len);
> @@ -393,14 +392,14 @@ int rxrpc_send_data_packet(struct rxrpc_call *call,
> struct sk_buff *skb,
> static int lose;
> if ((lose++ & 7) == 7) {
> ret = 0;
> - lost = true;
> + trace_rxrpc_tx_data(call, sp->hdr.seq, serial,
> + whdr.flags, retrans, true);
> + goto done;
> }
> }
>
> - trace_rxrpc_tx_data(call, sp->hdr.seq, serial, whdr.flags,
> - retrans, lost);
> - if (lost)
> - goto done;
> + trace_rxrpc_tx_data(call, sp->hdr.seq, serial, whdr.flags, retrans,
> + false);
>
> /* send the packet with the don't fragment bit set if we currently
> * think it's small enough */
> --
> 2.20.0
>
