On Wed, Apr 4, 2012 at 1:34 PM, Dominique Dhumieres <domi...@lps.ens.fr> wrote: >> >> We do have regular requests for this, so it is not just out of thin >> >> air. >> > >> > Perhaps, but I think that changing the default like this is far too >> > invasive. ?GCC should do what it's told, if a user asks for warnings, >> > give them, if they don't, then don't. >> >> It is hard to define "what it is told" means -- we are already in gray >> zone. >> >> > I suspect changing the default like this will generate a flood of >> > complaints. >> >> Really? Such as what? > > At least me!-(how many "regular requests" compared to the number of gcc > users?).
well, you can have a look at our bugzilla database, and look for -Wall for example and follow the discussions there. >> If we get floods of complaints, that can only that -Wall too many >> false positives; >> but I don't think it does. We have been careful over the years to >> watch for that effect. > > [macbook] gcc/work% grep ATTRIBUTE_UNUSED gcc/*.c | wc -l > 1060 > [macbook] gcc/work% grep ATTRIBUTE_UNUSED gcc/*.h | wc -l > 21 > > Doesn't that count as "false positives"? I said "too many false positive". I did not say "no false positive". What you would be more informative is the ratio of functions with that attribute over the number of function definitions. > IMO only the warnings in C that are likely errors should be the default as I can leave with that. However, here is the thing: We put in -Wall the warnings that are likely errors. I suspect if we find something in -Wall that are not likely errors, then that is an engineering bug from our part and we should fix it. > it is in gfortran (don't ask for examples of such warnings for C, I am > quasi-illiterate). > > > Dominique > > PS -Wall is a simple enough option to be remembered by all users who need > it (if they don't use it, they don't want it). The trouble is that most users find it an annoyance and don't remember. And they ask: if it is so simple, why isn't it included by default? This particular request came out of long discussions with people frustrated by the way GCC behaves compared to competitors.
