[Bug 40136] New: directx.c:4425:5: warning: comparison of unsigned expression < 0 is always false

https://bugs.winehq.org/show_bug.cgi?id=40136

Bug ID: 40136
           Summary: directx.c:4425:5: warning: comparison of unsigned
                    expression < 0 is always false
           Product: Wine
           Version: 1.9.3
          Hardware: x86
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: directx-d3d
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Noticed during compilation of wine-1.9.3-217-g0f8a0fd on older Debian Wheezy:

/wine_git_build/dlls/wined3d/directx.c: In function
‘wined3d_check_device_multisample_type’:

/wine_git_build/dlls/wined3d/directx.c:4425:5: warning: comparison of unsigned
expression < 0 is always false [-Wtype-limits]

[Bug 40136] directx.c:4425:5: warning: comparison of unsigned expression < 0 is always false

https://bugs.winehq.org/show_bug.cgi?id=40136

Wylda  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |source
       Distribution|---                         |Debian

--- Comment #1 from Wylda  ---
Filling some fields...

[Bug 40136] directx.c:4425:5: warning: comparison of unsigned expression < 0 is always false

https://bugs.winehq.org/show_bug.cgi?id=40136

Sergey Isakov  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |[e-mail]

--- Comment #2 from Sergey Isakov  ---
This is wrong programming style to check if enum type variable have a value out
of enum range.
For my mind the check must be at the function call and not inside the function.

Yes, the expression will never be < 0, this check is redundant.

[Bug 40136] directx.c:4425:5: warning: comparison of unsigned expression < 0 is always false

https://bugs.winehq.org/show_bug.cgi?id=40136

--- Comment #3 from Nikolay Sivov  ---
Why is that wrong? Function validates its argument, which can be anything.
Whether enum integer type is signed or not is compiler specific, for gcc and
this particular enum it will be unsigned int most likely, so more reliable
check would be to use (unsigned int)multisample_type >
WINED3D_MULTISAMPLE_16_SAMPLES.

[Bug 40136] directx.c:4425:5: warning: comparison of unsigned expression < 0 is always false

https://bugs.winehq.org/show_bug.cgi?id=40136

--- Comment #4 from Sergey Isakov  ---
It is not an error, it is redundant codes.

[Bug 40136] directx.c:4425:5: warning: comparison of unsigned expression < 0 is always false

https://bugs.winehq.org/show_bug.cgi?id=40136

Matteo Bruni  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |INVALID

--- Comment #5 from Matteo Bruni  ---
I guess we could cast to unsigned and only check for >
WINED3D_MULTISAMPLE_16_SAMPLES as Nikolay wrote but I don't see the current
code being wrong in any way.
Newer gcc doesn't complain, I guess the check became smarter.

[Bug 40136] directx.c:4425:5: warning: comparison of unsigned expression < 0 is always false

https://bugs.winehq.org/show_bug.cgi?id=40136

Austin English  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |CLOSED

--- Comment #6 from Austin English  ---
Closing.