[Mesa-dev] [PATCH 2/3] i965: Use unreachable() instead of unconditional assert().

[Philipp Klaus Krause]

On 30.06.2014 20:03, Matt Turner wrote:
> On Mon, Jun 30, 2014 at 10:37 AM, Ian Romanick <idr at freedesktop.org> wrote:
>> In the cases where a return (with a value) is removed, I'm afraid static
>> analysis tools will start to complain.  I'll be surprised if Klocwork
>> understands (or trusts) GCC __builtin_unreachable decorations.
> 
> Good catch. I didn't think about this.
> 
> I did a little bit of searching and discovered this page:
> 
> http://www.klocwork.com/products/documentation/current/Compiler_attributes_analyzed_by_Klocwork
> 
> which fortunately says that Klocwork recognizes gcc's
> __attribute__((noreturn)), so I feel relatively confident that
> Klocwork recognizes __builtin_unreachable as well.
> 
> If it doesn't and we get warnings from Klocwork, we can easily make
> the unreachable() macro expand to a static inline function marked with
> __attribute__((noreturn)).

Why use gcc-specific stuff instead of the standard _Noreturn/noreturn?

Philipp