Hi Justin, On Tue, Aug 15, 2023 at 12:11 AM Justin Stitt <justinstitt@xxxxxxxxxx> wrote: > When building with clang 18 I see the following warning: > | drivers/soc/renesas/rmobile-sysc.c:193:22: warning: cast to smaller integer > | type 'enum pd_types' from 'const void *' [-Wvoid-pointer-to-enum-cast] > | 193 | add_special_pd(np, (enum pd_types)id->data); > > This is due to the fact that `id->data` is a void* and `enum pd_types` > has the size of an integer. This cast from pointer-width to int-width > causes truncation and possible data loss. Instead, cast to `uintptr_t` > which has the same width as void*. > > Link: https://github.com/ClangBuiltLinux/linux/issues/1910 > Reported-by: Nathan Chancellor <nathan@xxxxxxxxxx> scripts/checkpatch.pl: WARNING: Reported-by: should be immediately followed by Closes: with a URL to the report Hence changing the Link: tag to a Closes: tag. > Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx> > --- > Note: It should be noted that there is likely no data loss occurring in > this case since the enum only has a few fields. The narrowing cast from > pointer to int will not lose any data. Indeed, the theoretical narrowing could only happen on a 64-bit platform, while this driver is only used on arm32. Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> i.e. will queue in renesas-devel for v6.7. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
