On 8 April 2012 16:16, James Cloos wrote: > > Sure. Making a few more of the -W flags on by default may be OK, > depending on the chosen list. It is the idea of turing all possible > warning options on by default which is unreasonable.
Noone's suggested doing that. As Gaby said, -Wall doesn't turn on all warnings. > Defaulting to -Wall also fails as a user interface design. -Wall is > a nice, short, sweet, easy to type optiong which one readily can add > at any time. So is -Wno-all > Forcing one to have to find all of the -Wno-... options > to avoid unwanted annoyances, That applies even if -Wall isn't on by default. People who use -Wall (which means lots of people) still have to use -Wno-xxx to disable the warnings they don't want. Making -Wall on by default doesn't change that. Anyway, GCC prints the option that controls a warning as part of the diagnostic, so it's trivial to find which options control the diagnostics that are annoying you. > or to the -Wno-all and a set of -Ws > which one does want is far more cumbersome. Why is using -Wno-all -Wfoo -Wbar "far more cumbersome" than what you have to do to get the same effect today? i.e. -Wfoo -Wbar Those points apply equally to what we have today and so aren't really relevant to whether -Wall should be on by default or not. > And what if new warning are added. Does anyone really want them *all* > on by default as soon as the code lands? That argument also applies equally to -Wall as it is today, maintainers need to decide if new warnings should be included in -Wall or not, as that affects everyone who uses -Wall (which is a large number of users.) That wouldn't be any different if -Wall was enabled by default. > If there are some useful warning not already on by default which tend > not to false-positive and provide useful, beneficial information when > triggered, then it is reasonable to look into starting to default-enable > them. That's not far from what has been proposed (although -Wall currently contains some warnings that don't fit into that category, so maybe a -Wstandard set would be useful. > Turning *all* of them on willy-nilly is not. Noone's suggesting that. FWIW we do sometimes have to close invalid bugzilla reports that complain about no warning when the user simply failed to use -Wall, or because the code is clearly wrong and they would have been told so if they'd just used -Wall. That does imply that people who don't know what they're doing (and so might benefit most from enabling warnings) aren't aware of -Wall. The people who don't want -Wall (or -Wstandard) enabled are likely to be the ones who know how to use -Wno-all or whatever to get what they want.
