On Fri, Oct 06, 2023 at 06:45:08PM +0200, Thomas Huth wrote:
> Avoid using trivial variable names in macros, otherwise we get
> the following compiler warning when compiling with -Wshadow=local:
>
> In file included from ../../qemu/hw/display/virtio-gpu-virgl.c:19:
> ../../home/thuth/devel/qemu/hw/display/virtio-gpu-virgl.c:
> In function ‘virgl_cmd_submit_3d’:
> ../../qemu/include/hw/virtio/virtio-gpu.h:228:16: error: declaration of ‘s’
> shadows a previous local [-Werror=shadow=compatible-local]
> 228 | size_t s;
> | ^
> ../../qemu/hw/display/virtio-gpu-virgl.c:215:5: note: in expansion of macro
> ‘VIRTIO_GPU_FILL_CMD’
> 215 | VIRTIO_GPU_FILL_CMD(cs);
> | ^~~~~~~~~~~~~~~~~~~
> ../../qemu/hw/display/virtio-gpu-virgl.c:213:12: note: shadowed declaration
> is here
> 213 | size_t s;
> | ^
> cc1: all warnings being treated as errors
>
> Signed-off-by: Thomas Huth <th...@redhat.com>
> ---
> include/hw/virtio/virtio-gpu.h | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/include/hw/virtio/virtio-gpu.h b/include/hw/virtio/virtio-gpu.h
> index 390c4642b8..8b7e3faf01 100644
> --- a/include/hw/virtio/virtio-gpu.h
> +++ b/include/hw/virtio/virtio-gpu.h
> @@ -225,13 +225,13 @@ struct VhostUserGPU {
> };
>
> #define VIRTIO_GPU_FILL_CMD(out) do { \
> - size_t s; \
> - s = iov_to_buf(cmd->elem.out_sg, cmd->elem.out_num, 0, \
> + size_t s_; \
> + s_ = iov_to_buf(cmd->elem.out_sg, cmd->elem.out_num, 0, \
> &out, sizeof(out)); \
> - if (s != sizeof(out)) { \
> + if (s_ != sizeof(out)) { \
> qemu_log_mask(LOG_GUEST_ERROR, \
> "%s: command size incorrect %zu vs %zu\n", \
> - __func__, s, sizeof(out)); \
> + __func__, s_, sizeof(out)); \
> return; \
> } \
> } while (0)
This is not really enough I think. Someone might
use another macro as parameter to this macro and we'll get
a mess. We want something that's specific to this macro.
How about VIRTIO_GPU_FILL_CMD_s ?
> --
> 2.41.0
