Bug 12663
| Summary: | Ambiguous if statement | ||
|---|---|---|---|
| Product: | Base System | Reporter: | Adam Wight <adamw> |
| Component: | kern | Assignee: | freebsd-bugs (Nobody) <bugs> |
| Status: | Closed FIXED | ||
| Severity: | Affects Only Me | ||
| Priority: | Normal | ||
| Version: | 4.0-CURRENT | ||
| Hardware: | Any | ||
| OS: | Any | ||
Adam Wight writes:
>
> >Number: 12663
> >Category: kern
> >Synopsis: Ambiguous if statement
> >Confidential: no
> >Severity: non-critical
> >Priority: low
> >Responsible: freebsd-bugs
> >State: open
> >Quarter:
> >Keywords:
> >Date-Required:
> >Class: change-request
> >Submitter-Id: current-users
> >Arrival-Date: Fri Jul 16 02:40:01 PDT 1999
> >Closed-Date:
> >Last-Modified:
> >Originator: Adam Wight
> >Release: FreeBSD 4.0-CURRENT i386
> >Organization:
> >Environment:
> all
>
> >Description:
> The file sys/i386/apm/apm.c contains an ambiguous if...else statement
> that appears to be parsed correctly by the compiler, but could break
> silently depending on the compiler release.
No, they could not break silently, as the syntax is guaranteed to be
correct by the ANSI-C standard. If it broke, the compiler would be
broke and a number of other such code in many systems would also break.
Nate
Nate Williams writes:
> No, they could not break silently, as the syntax is guaranteed to be
> correct by the ANSI-C standard. If it broke, the compiler would be
> broke and a number of other such code in many systems would also break.
You might be right, Nate. But I forgot to fix it up when I ported
the code from NetBSD's one. Also I like a lot the style as Mr. Adam Wight
pointed out because It is preventible from missing { and } when few more
lines are needed in the block afterward.
Thank you Adam and Nate, I'll fix it soon if there is no objections.
State Changed From-To: open->closed Fixed. Thanks! |
The file sys/i386/apm/apm.c contains an ambiguous if...else statement that appears to be parsed correctly by the compiler, but could break silently depending on the compiler release. Fix: Sorry, you might have to use patch -l... =================================================================== RCS file: /usr/cvs/src/sys/i386/apm/apm.c,v retrieving revision 1.90 ! if (events & (POLLIN | POLLRDNORM)) ! if (sc->event_count) revents |= events & (POLLIN | POLLRDNORM); ! else selrecord(p, &sc->sc_rsel); return (revents); } --- 1283,1295 ---- struct apm_softc *sc = &apm_softc; int revents = 0; ! if (events & (POLLIN | POLLRDNORM)) { ! if (sc->event_count) { revents |= events & (POLLIN | POLLRDNORM); ! } else { selrecord(p, &sc->sc_rsel); + } + } return (revents); }--Ng5dN5MzwZo8Ju70fMly3qGf2dDWIN4JMGhMij3ow1dQw9kV Content-Type: text/plain; name="file.diff" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="file.diff" diff -c -r1.90 apm.c *** apm.c 1999/07/10 18:08:48 1.90 --- apm.c 1999/07/13 17:45:38 *************** *** 1283,1293 **** struct apm_softc *sc = &apm_softc; int revents = 0;