Coreboot build process with gcc 8.1

[Salvatore Bellizzi]

Hi,
I have a question reguarding the build process.

Since crossgcc has been updated and gcc is now at version 8.1 I always
encounter an error when building coreboot:

coreboot/src/console/vtxprintf.c:102: undefined reference to
'__udivmoddi4'

Since coreboot uses crossgcc and its own libgcc libraries, I figured
that the __udivmoddi4 function has not yet been implemented.

Anyway I have incurred in this failure several times and even with the
latest 4.9 release. Shouldn't I be able to build at least this latest
release using unmodified crossgcc or am I missing something else?

thanks,
salvatore

[Angel Pons]

Hello Salvatore,

On Sat, Dec 29, 2018, 12:24 Salvatore Bellizzi <[e-mail] wrote:
> Hi,
> I have a question reguarding the build process.
>
> Since crossgcc has been updated and gcc is now at version 8.1 I always
> encounter an error when building coreboot:
>
> coreboot/src/console/vtxprintf.c:102: undefined reference to
> '__udivmoddi4'

If I remember properly, this happens when using the x86_64 (64-bit)
toolchain with coreboot for x86 mainboards, on which coreboot runs in
32-bit mode. The older x86_64 GCC6 toolchain had a multilib patch which
allowed it to compile to i386 (32-bit) machine code, which is why it worked
fine. However, the x86_64 GCC8 toolchain does not have the aforementioned
patch and fails.

Since coreboot uses crossgcc and its own libgcc libraries, I figured
> that the __udivmoddi4 function has not yet been implemented.
>
> Anyway I have incurred in this failure several times and even with the
> latest 4.9 release. Shouldn't I be able to build at least this latest
> release using unmodified crossgcc or am I missing something else?

Definitely, you should be able to, but you need crossgcc-i386 to build
coreboot for x86 platforms.

thanks,
> salvatore

Best regards,

Angel Pons
>

[Salvatore Bellizzi]

On Sat, 2018-12-29 at 12:38 +0100, Angel Pons wrote:
> Hello Salvatore,
>
> On Sat, Dec 29, 2018, 12:24 Salvatore Bellizzi <[e-mail] wrote:
> > Hi,
> > I have a question reguarding the build process.
> >
> > Since crossgcc has been updated and gcc is now at version 8.1 I always
> > encounter an error when building coreboot:
> >
> > coreboot/src/console/vtxprintf.c:102: undefined reference to
> > '__udivmoddi4'
>
> If I remember properly, this happens when using the x86_64 (64-bit)
> toolchain with coreboot for x86 mainboards, on which coreboot runs in
> 32-bit mode. The older x86_64 GCC6 toolchain had a multilib patch which
> allowed it to compile to i386 (32-bit) machine code, which is why it worked
> fine. However, the x86_64 GCC8 toolchain does not have the aforementioned
> patch and fails.

That was it. I thought I didn't need the i386 toolchain since I was
building for an x86_64 board but I was evidently mistaken. After
building also the i386 GCC8 toolchain I was able to successfully build
coreboot 4.9 stable and from master branch too.

Thank you Angel,

Salvatore Bellizzi