On Mon, Nov 24, 2025 at 01:20:21PM -0800, Kees Cook wrote:
> Yes, -Wconversion (W=3) is mind-blowingly noisy, unfortunately.
This third one is interesting.
include/linux/jump_label.h:126:44: error: conversion to ‘long unsigned int’
from ‘s32’ {aka ‘int’} may change the sign of the result
[-Werror=sign-conversion]
126 | return (unsigned long)&entry->code + entry->code;
static inline unsigned long jump_entry_code(const struct jump_entry *entry)
{
return (unsigned long)&entry->code + entry->code;
}
The warning is ... not the best phrased, but in terms of divining the
programmer's intent, I genuinely don't know if this code is supposed
to zero-extend or sign-extend the s32 to unsigned long. I know what it
*does*, but I don't know if it was *supposed to do that*. So I wuold be
in favour of enabling this warning ... if we have a small army of people
on tap to get the kernel to build. There's 374 lines of errors to fix
from the header files included by scripts/mod/devicetable-offsets.s alone.
