Re: multiboot

[Marco Gerards <metgerards@student.han.nl>]

Johan Rydberg <jrydberg@night.trouble.net> writes:

> Marco Gerards <metgerards@student.han.nl> writes:
>
>> Johan Rydberg <jrydberg@night.trouble.net> writes:
>>
>>> The initial problem was that AC_CHECK_SIZEOF doesn't work if you're
>>> cross-compiling.  I fixed this by using AC_COMPILE_CHECK_SIZEOF [1]
>>> instead.
>>
>> This sounds right to me, but I do not see this in the patch...
>
> Of course not.  I didn't include it :) I'm sure you can download the
> m4 macro, install it in acinclude.m4 and change AC_CHECK_SIZEOF to
> AC_COMPILE_CHECK_SIZEOF.  If you're as lazy as I am, I can include it
> in a later patch.

As you know, I am lazy... ;)

>>> But the major problem is that parts of GRUB2 requires a C library to
>>> be installed, at least headers such as alloca.h and stdint.h.  Is this
>>> really a valid demand?  
>>
>> Is this required for grubof?  IIRC those headers are not a part of the
>> C library, but a part of gcc or libgcc or so.  Am I right about that?
>
> My GCC installation (3.2.2 configured for powerpc-elf) installed the
> following headers:

[...]

> A little more research shows that both stdint.h and alloca.h is part
> of glibc:

[...]

> So either we stop using then, or write our own versions.

Ok, agreed.

>> Instead of alloca we can also use something like:
>> [...]
>> In most cases that will remove the dependency on alloca.  IMHO it is
>> better not to use alloca.
>
> It is also possible to use __builtin_alloca if alloca.h is missing,
> provided that there's a requirement for GCC.  

There is a gcc requirement already, that is not a problem.

Thanks,
Marco