Re: [PATCH v4] sparse: add -Wpointer-arith flag to toggle sizeof(void) warnings

[Luc Van Oostenryck]

On Tue, Apr 10, 2018 at 12:46:24PM -1000, Joey Pabalinas wrote:
> Recent changes to the min()/max() macros in include/linux/kernel.h
> have added a lot of noise when compiling the kernel with Sparse checking
> enabled. This mostly is due to the *huge* increase in the number of
> sizeof(void) warnings, a larger number of which can safely be ignored.
> 
> Add the -Wpointer-arith flag to enable/disable these warnings (along
> with the warning when applying sizeof to function types as well as
> warning about pointer arithmetic on these types exactly like the
> GCC -Wpointer-arith flag) on demand; the warning itself has been disabled
> by default to reduce the large influx of noise which was inadvertently
> added by commit 3c8ba0d61d04ced9f8 (kernel.h: Retain constant expression
> output for max()/min()).
> 
> Update the manpage to document the new flag and add a validation case
> for sizeof(void).
> 
> CC: Kees Cook <keescook@xxxxxxxxxxxx>
> CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> CC: Martin Uecker <Martin.Uecker@xxxxxxxxxxxxxxxxxxxxx>
> CC: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
> CC: Christopher Li <sparse@xxxxxxxxxxx>
> CC: Joey Pabalinas <joeypabalinas@xxxxxxxxx>
> CC: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
> Signed-off-by: Joey Pabalinas <joeypabalinas@xxxxxxxxx>
> Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>

Thanks,
Acked-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>