On Mon, Oct 28, 2019 at 08:32:42PM +0100, Rasmus Villemoes wrote: > Hi, > > I just spent some time trying to convert some so far PPC-only drivers to > be more generic. One of the things I had to do was convert stuff like > > u32 *val = of_get_property(np, "bla", NULL); > do_stuff_with(*val); > > with > > of_property_read_u32(np, "bla", &val); > do_stuff_with(val); > > (error checking omitted for simplicity). The problem is that > of_get_property() just returns void*. When the property is just a > string, there's no problem interpreting that as a char*. But when the > property is a number of array of numbers, I'd like some way to flag > casting it to u32* as an error - if you cast it to a (pointer to integer > type wider than char), it must be to a __be32*. Is there some way > sparse/smatch could help find such cases? If I understand you correctly, you would need a kind of 'soft' bitwise pointer? I guess it shouldn't be too hard to add a new flag which would allow cast of bitwise pointers to pointers to char/void (see at end of evaluate.c:evaluate_cast()). Note: casts from bitwise pointer to void* are already allowed. -- Luc
