Does that work or generate an warning about statement with no effect? Gedare Bloom <ged...@rtems.org> wrote:
On Sun, Sep 22, 2013 at 10:45 AM, Joel Sherrill <joel.sherr...@oarcorp.com> wrote: > There is precedence for using the compiler attributes > so I just added that and switched. > I think it might be better to avoid compiler attributes when there is a language-level alternative that is compiler-agnostic. In this case, the use of: (void) var; seems fine to me. > Thanks for the feedback. > > If we have a print format string to use for mode_t and > wchar_t, a few more cases would be fixed. > > On 9/22/2013 7:32 AM, Pavel Pisa wrote: >> Hello Ralf and others, >> >> On Sunday 22 of September 2013 05:01:49 Ralf Corsepius wrote: >>>> diff --git a/cpukit/posix/src/semopen.c b/cpukit/posix/src/semopen.c >>>> index b863080..e61fad0 100644 >>>> --- a/cpukit/posix/src/semopen.c >>>> +++ b/cpukit/posix/src/semopen.c >>>> @@ -43,6 +43,14 @@ >>>> * parameters must be present. >>>> */ >>>> >>>> +/* >>>> + * mode is set but never used. GCC gives a warning for this >>>> + * and we need to tell GCC not to complain. But we have to >>>> + * have it because we have to work through the variable >>>> + * arguments to get to attr. >>>> + */ >>>> +#pragma GCC diagnostic push >>>> +#pragma GCC diagnostic ignored "-Wunused-but-set-variable" >>>> sem_t *sem_open( >>>> const char *name, >>>> int oflag, >>>> @@ -137,3 +145,4 @@ return_id: >>>> return (sem_t *)&the_semaphore->Object.id; >>>> #endif >>>> } >>>> +#pragma GCC diagnostic pop >>> >>> Why this brutal and probably non-portable way to suppress warnings? >>> >>> Why doesn't __attribute__((unused)) or similar suffice? >> >> I would prefer to see something like RTEMS_ATTR_UNUSED to support >> multiple compilers. You can look at my collection of these in >> uLUt definitions file >> >> http://sourceforge.net/p/ulan/ulut/ci/master/tree/ulut/ul_utdefs.h >> >> I declare file contents (by this e-mail) as free for public >> domain use (uLUt as whole is is GPL/LGPL/MPL RTEMS compatible too). >> >> As for the actual __attribute__((unused)) there is even portable >> solution which does not depend on GCC extension. >> >> { >> int my_unused_var; >> (void) my_unused_var; >> } >> >> This solution should be accepted by all compilers and is suggested >> by some people as better option. >> >> Best wishes, >> >> Pavel >> _______________________________________________ >> rtems-devel mailing list >> rtems-devel@rtems.org >> http://www.rtems.org/mailman/listinfo/rtems-devel >> > > > > -- > Joel Sherrill, Ph.D. Director of Research & Development > joel.sherr...@oarcorp.com On-Line Applications Research > Ask me about RTEMS: a free RTOS Huntsville AL 35805 > Support Available (256) 722-9985 > _______________________________________________ > rtems-devel mailing list > rtems-devel@rtems.org > http://www.rtems.org/mailman/listinfo/rtems-devel _______________________________________________ rtems-devel mailing list rtems-devel@rtems.org http://www.rtems.org/mailman/listinfo/rtems-devel
