On Wed, Dec 06, 2023 at 12:01:56AM +0200, Andy Shevchenko wrote: > On Tue, Dec 05, 2023 at 01:51:10PM -0800, Nick Desaulniers wrote: > > On Tue, Dec 5, 2023 at 1:38 PM Al Viro <v...@zeniv.linux.org.uk> wrote: > > > On Tue, Dec 05, 2023 at 08:58:53PM +0000, tanz...@google.com wrote: > > ... > > > > > IWYU is implemented using the IWYUScripts github repository which is a > > > > tool that is > > > > currently undergoing development. These changes seek to improve build > > > > times. > > > > > > > > This change to lib/string.c resulted in a preprocessed size of > > > > lib/string.i from 26371 lines to 5232 lines (-80%). > > > > > > It also breeds includes of asm/*.h, by the look of the output, which is > > > not a good thing in general ;-/ E.g. #include <asm/uaccess.h> *anywhere* > > > outside of linux/uaccess.h is a bad idea. > > > > It's not clear to me when it's ok to #include <asm/*.h>. Is there a > > convention here that I'm missing? > > The mandatory ones can be used, but not all of them. > In some cases you even must include asm and not linux > (unaligned.h, byteorder.h, maybe others...). > > As I told, it comes with experience, we lack of the > respective documentation (or file which is good for > automation checks, like with IWYU).
It would certainly be nice to have such information in the tree; "where should I pick $SYMBOL from?" is something one needs to find out often enough. To a large extent it's covered by "where in include/*.h do we have it defined?", but that's not all there is to it. E.g. "get_user() => use linux/uaccess.h". There's also stuff like "$SYMBOL should not be used outside of arch/* and include/*, better use $OTHER_SYMBOL", etc.
