Re: [Qemu-devel] [PATCH RFC] main loop: fix some accesses made in sighandler context

[Laszlo Ersek]

On 09/15/11 21:44, Peter Maydell wrote:
> On 15 September 2011 18:22, Laszlo Ersek<address@hidden>  wrote:
> > -int no_shutdown = 0;
> > +volatile int no_shutdown = 0;
>
> So why 'volatile' and not 'sig_atomic_t', then?

The sigaction() spec  says"volatile sig_atomic_t", so that would be 
ideal. My assumption was that "sig_atomic_t" (which is allowed by POSIX 
not to be wider than "char") would be in practice at least as wide as 
"int" and "pid_t". Should my assumption be wrong on some platforms, 
qualifying the variables "volatile" while keeping their current types 
(int / pid_t) does less damage (no damage) than narrowing their types.

lacos