Re: Nonexistance of asm/offsets.h

On 7/13/07, Jeff Bailey <[email protected]> wrote:
> In the process of getting the world up, running and debugged with
> NPTL, Randolph has provided a patch to make gdb work better.  Building
> this on Ubuntu turned out to be a problem because we're using the
> exported kernel headers rather than the mashup that Debian has been
> using.
>
> The challenge is that the Debian kernel packages used to generate
> asm/offsets.h from the 64-bit kernel build's asm-offsets.h and make
> that available.  When we created linux-kernel-headers, we just
> imported that.
>
> Now, with the sanitised kernel headers being produced from the kernel
> source, this no longer seems right.  It means that there's a header
> that's not right for both 32-bit and 64-bit userspace, and it's being
> generated, so it might change by accident and break the userspace ABI.
>  I'd like to propose that we create a hand-crafted offsets.h that is
> intended for userspace consuption and then stop generating the
> asm-offsets.h file at build time.  I'll put together a patch to do
> this over the weekend unless there's objections.

In theory a 64-bit configured kernel should generate both a 32-bit and
64-bit versions of asm-offets.h. IIRC other arches use a wrapper
asm-offets.h that checks for a compiler builtin define e.g. __hppa64__
to select the right 32 or 64-bit header.

Cheers,
Carlos.