[Mesa-dev] 答复: Re: screen blurred and glxgears segment fault on ubuntu17.10 for arm architecture server with amdgpu(AMD RADEON PRO WX7100)

[Matt Turner]

On Tue, Dec 5, 2017 at 8:18 PM, Lvzhihong (ReJohn)
<lvzhihong1 at huawei.com> wrote:
> Hi Michel,
>
>         We solve the glxgears segmentation fault problem by add the compile flags: -fsigned-char.
>         In arm platform, char variant default to "unsigned-char", that makes problem of glxgears segmentation fault.

Well done.

On x86/amd64 "char" is signed, but on arm it is unsigned. See
https://ajax.fedorapeople.org/is-char-signed-or-not.txt and
https://trofi.github.io/posts/203-signed-char-or-unsigned-char.html

I wonder if Coccinelle is capable of detecting cases where chars are
compared with -1, etc.