Re: Dead Code

[Joel Sherrill <joel dot sherrill at oarcorp dot com>]

On 3/15/2017 11:51 AM, Craig Howland wrote:
> On 03/15/2017 11:48 AM, Joel Sherrill wrote:
> > Hi
> >
> > I think Coverity spotted a case where an || should be an &&
> > in libc/string/strsignal.c. What does everyone else think?
> >
> >  74#if defined(SIGRTMIN) && defined(SIGRTMAX)
> >        cond_at_most: Condition signal >= 27, taking false branch. Now the
> > value of signal is at most 26.
> >        at_most: At condition signal <= 31, the value of signal must be at most
> > 26.
> >        dead_error_condition: The condition signal <= 31 must be true.
> >  75  if ((signal >= SIGRTMIN) || (signal <= SIGRTMAX)) {
> >  76    siprintf (buffer, "Real-time signal %d", signal - SIGRTMIN);
> >  77    return buffer;
> >  78  }
> >  79#endif
> >  80
> >
> > CID 175333 (#1 of 1): Logically dead code (DEADCODE)
> > dead_error_line: Execution cannot reach this statement: switch (signal) {
> >
> >   case 1:....
> >
> > --joel
> I agree.  (Very easy to test, for that matter.)

I was thinking the same thing about a test and was
writing one while waiting for some feedback. Based
on this output, it is definitely broken!!

=== Normal Signals

signal=SIGHUP => Real-time signal -26
signal=SIGINT => Real-time signal -25
signal=SIGQUIT => Real-time signal -24
signal=SIGILL => Real-time signal -23

It also looks like I wrote this code so I should
take my lashings with a wet noodle. :)

Patch coming shortly.

Thanks for the review. I hope you will join in
and take a look at some of them.

--joel

> Craig