> -----Original Message----- > From: > avr-gcc-list-bounces+eric.weddington=atmel....@nongnu.org > [mailto:avr-gcc-list-bounces+eric.weddington=atmel....@nongnu. > org] On Behalf Of David Brown > Sent: Saturday, March 27, 2010 5:34 PM > To: Szikra Istvan; avr-gcc-list@nongnu.org > Subject: Re: [avr-gcc-list] Re: Inline vs. ? : operator > > > My other problem with this is, it only "returns a value" when it's > > executed indirectly (contained in a function, that provides it's c > > parameter as a variable!). For example it does not generate an 'in' > > instruction in the main program (function). If you were right about > > that ?: should read the volatile twice, then it should happen at the > > first bit_write() statement in the main function too. > > > > I didn't notice this earlier. But this behaviour, I believe, is the > erroneous behaviour. > > It would seem that this situation is not entirely clear - the > compiler > should at least be consistent. But it's not obvious what the correct > behaviour should be. Note that we are concerned here about getting > /correct/ code - not necessarily the smallest and fastest code. > > Perhaps some of those more familiar with the internals of gcc > and/or the > C standards may like to comment. Otherwise, I'd recommend > avoiding the > ?: operator with volatiles - stick to code that you know > works correctly > and optimally. >
I will only comment on this when I see a well-formed bug report in the GCC bug database: <http://gcc.gnu.org/bugzilla/> It must include a buildable test case that shows the alleged issue. _______________________________________________ AVR-GCC-list mailing list AVR-GCC-list@nongnu.org http://lists.nongnu.org/mailman/listinfo/avr-gcc-list
