On Wed, Dec 16, 2009 at 07:41:45AM -0500, James Carlson wrote: > Fedor Sergeev wrote: > > By the way, as we are likely to revisit -erroff implementation, I would > > like to > > ask this mailing list - do you have any ideas on -erroff/-errwarn interface > > improvement? > > Something that you always thought about but were too shy to ask? ;) > > Not quite on those flags (which seem to work well enough), but there is > an old RFE I filed some years ago to allow for better printf/scanf > format string versus argument checking.
Eh... thats kind of a huuuge way off the topic :) > > As you likely know, there are quite a few printf/scanf variants around > besides the libc standards-compliant ones. For example, the formatting > in the kernel is different because there's no floating point and there > are a few extra formatting specifiers. Mdb has an internal printf > mechanism that has quite a few additional specifiers. Syslog has "%m". > > Unfortunately, you really can't use PRINTFLIKE or SCANFLIKE unless it's > identical to the standards-complaint functions. If it's not, then the > checking is off by a bit -- or possibly by a lot. Many of those things > are now just flying blind. > > It would be nice to have a way to tell the compiler and/or lint that a > given function has printf/scanf behavior with some exceptions, and allow > the implementor to specify how specifiers and modifiers work for that > function. One of the biggest issues here would be to figure out proper user interface. Is there any gcc extension that does something useful for this matter? I dont remember one right away. regards, Fedor.
