https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68993
--- Comment #6 from Steve Kargl <sgk at troutmask dot apl.washington.edu> --- On Mon, Dec 21, 2015 at 08:29:57PM +0000, Joost.VandeVondele at mat dot ethz.ch wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68993 > > --- Comment #5 from Joost VandeVondele <Joost.VandeVondele at mat dot > ethz.ch> --- > (In reply to Steve Kargl from comment #4) > > > > I would urge anyone trying to be clever to use clear syntax: > > > > https://github.com/hfp/libxsmm/commit/cc308fc5debe6151157a4fa9efacc7aa03351283 > > is what we used indeed, but it is not quite as concise as one would like. > Interesting project. I may need to take a closer look at it. I agree that the suggested syntax is not concise. In your particular case, you could write cpa = C_NULL_PTR IF (PRESENT(pa)) cpa = C_LOC(pa) instead of IF (PRESENT(pa)) THEN cpa = C_LOC(pa) ELSE cpa = C_NULL_PTR END IF This would reduce your code from 15 lines to 6 lines. I'll note that in some testing where I had a similar code structure the former (ie., 2-line example) was slower than the latter (5-line example). It is unfortanute that Fortran does not have a ternary operator. This is a good example where it might be nice to have cpa = present(pa) ? c_loc(pa) : c_null_ptr where the TRUE or FALSE choice is only evaluated based on the condition.
