2016-11-16 14:20:57

by Arnd Bergmann

[permalink] [raw]
Subject: [PATCH] drm/vmwgfx: avoid gcc-7 parentheses warning

gcc-7 warns about slightly suspicious code in vmw_cmd_invalid:

drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c: In function 'vmw_cmd_invalid':
drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c:522:23: error: the omitted middle operand in ?: will always be 'true', suggest explicit middle operand [-Werror=parentheses]

The problem is that it is mixing boolean and integer values here.
I assume that the code actually works correctly, so making it use
a literal '1' instead of the implied 'true' makes it more readable
and avoids the warning.

The code has been in this file since the start, but it could
make sense to backport this patch to stable to make it build cleanly
with gcc-7.

Fixes: fb1d9738ca05 ("drm/vmwgfx: Add DRM driver for VMware Virtual GPU")
Signed-off-by: Arnd Bergmann <[email protected]>
---
drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
index c7b53d987f06..3f343e55972a 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
@@ -519,7 +519,7 @@ static int vmw_cmd_invalid(struct vmw_private *dev_priv,
struct vmw_sw_context *sw_context,
SVGA3dCmdHeader *header)
{
- return capable(CAP_SYS_ADMIN) ? : -EINVAL;
+ return capable(CAP_SYS_ADMIN) ? 1 : -EINVAL;
}

static int vmw_cmd_ok(struct vmw_private *dev_priv,
--
2.9.0


2016-11-17 02:25:26

by Sinclair Yeh

[permalink] [raw]
Subject: Re: [PATCH] drm/vmwgfx: avoid gcc-7 parentheses warning

Looks good to me, thanks!
I'll incorporate this into the next pull request.

Reviewed-by: Sinclair Yeh <[email protected]>

On Wed, Nov 16, 2016 at 03:19:31PM +0100, Arnd Bergmann wrote:
> gcc-7 warns about slightly suspicious code in vmw_cmd_invalid:
>
> drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c: In function 'vmw_cmd_invalid':
> drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c:522:23: error: the omitted middle operand in ?: will always be 'true', suggest explicit middle operand [-Werror=parentheses]
>
> The problem is that it is mixing boolean and integer values here.
> I assume that the code actually works correctly, so making it use
> a literal '1' instead of the implied 'true' makes it more readable
> and avoids the warning.
>
> The code has been in this file since the start, but it could
> make sense to backport this patch to stable to make it build cleanly
> with gcc-7.
>
> Fixes: fb1d9738ca05 ("drm/vmwgfx: Add DRM driver for VMware Virtual GPU")
> Signed-off-by: Arnd Bergmann <[email protected]>
> ---
> drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
> index c7b53d987f06..3f343e55972a 100644
> --- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
> +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
> @@ -519,7 +519,7 @@ static int vmw_cmd_invalid(struct vmw_private *dev_priv,
> struct vmw_sw_context *sw_context,
> SVGA3dCmdHeader *header)
> {
> - return capable(CAP_SYS_ADMIN) ? : -EINVAL;
> + return capable(CAP_SYS_ADMIN) ? 1 : -EINVAL;
> }
>
> static int vmw_cmd_ok(struct vmw_private *dev_priv,
> --
> 2.9.0
>