> On 19 Jan 2023, at 21:20, Paul Eggert <eggert@cs.ucla.edu> wrote:
> 
> On 1/19/23 12:44, Sam James wrote:
>> _Noreturn is pretty much just an optimisation (and I'm not convinced that it's _needed_  in a lot of cases, rather just a useful hint).
> 
> _Noreturn is not just an optimization: it's also useful for static checking. For example:
> 
>  int
>  f (int x)
>  {
>     if (x < INT_MAX)
>       return x + 1;
>     error (1, 0, "x is too large");
>  }
> 
> Since error is _Noreturn the compiler knows not to warn that F might return garbage. It's useful to suppress false alarms, even when Clang is the compiler.
> 

Right, I just meant that we don't tend to care about quieting warnings with older compilers,
and it's not useful from a static analysis perspective here either given that older Clangs can't be trusted.

It is of course useful as an attribute in general. I don't think either of these things are really
a downside to committing the workaround here. If we get folks who get build failures with extra warnings
enabled, we can tell them to upgrade their compiler.