# Gentoo Sources 4.1.12 - V4L2 [SOLVED]

## thiagofanfoni

Hi guys

I've just tried to update my laptop with the latest stable release of gentoo-sources (4.1.12) but the compilation is failing with V4L2.

This module is a dependency of uvc (needed for my webcam).

```

drivers/media/v4l2-core/videobuf2-core.c: In function ‘vb2_warn_zero_bytesused’:

drivers/media/v4l2-core/videobuf2-core.c:1248:2: error: implicit declaration of function ‘__WARN’ [-Werror=implicit-function-declaration]

  __WARN();

  ^

cc1: some warnings being treated as errors

scripts/Makefile.build:264: recipe for target 'drivers/media/v4l2-core/videobuf2-core.o' failed

make[3]: *** [drivers/media/v4l2-core/videobuf2-core.o] Error 1

scripts/Makefile.build:403: recipe for target 'drivers/media/v4l2-core' failed

make[2]: *** [drivers/media/v4l2-core] Error 2

scripts/Makefile.build:403: recipe for target 'drivers/media' failed

make[1]: *** [drivers/media] Error 2

Makefile:947: recipe for target 'drivers' failed

make: *** [drivers] Error 2

```

Someone else is having this problem?

CheersLast edited by thiagofanfoni on Sun Nov 08, 2015 2:38 am; edited 1 time in total

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## Roman_Gruber

a) try a newer kernel (4.2.x is longterm kernel org stable release anyway)

b) toolchain up to date?

c) lack of information => emerge --info

suggested a) (it does not hurt unmasking newer kernel=

c)

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## netfab

For the build error : https://lkml.org/lkml/2015/7/12/172

A patch was sent : https://lkml.org/lkml/2015/7/12/163

But I don't know if it was reviewed/accepted.

You should open a bug at b.g.o to track this, and, in the meanwhile, you should try to enable CONFIG_BUG in the kernel configuration.

```

$ zgrep CONFIG_BUG /proc/config.gz

CONFIG_BUG=y

```

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## thiagofanfoni

Thanks guys, I've never had a problem with the gentoo-sources stable before.

I've upgraded to 4.2.5 and was able to build the kernel and the nvidia modules as well.

I'll open this bug, but what is b.g.o. ?

Thanks again   :Very Happy: 

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## TigerJr

 *tw04l124 wrote:*   

> a) try a newer kernel (4.2.x is longterm kernel org stable release anyway)
> 
> b) toolchain up to date?
> 
> c) lack of information => emerge --info
> ...

 

Haha, new kernel - stable release!? And how did you know that? Tested on many peoples and many configurations?

And than hi confronted with BUG, than you advice them update to release candidate kernel?

p\S

What are differs us:

You are believe developers, but i'm already - NOT, cause: 

one bug solved - two bugs new, two bugs solved - one bug new, new modules - new bugs, new kernel - new modules... and than all begins again!

So if you are didn't know what major\minor version number does and didn't reading changelog of kernel, don't give a people suicide advices.

trust but test and verify

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## netfab

 *thiagofanfoni wrote:*   

> 
> 
> I'll open this bug, but what is b.g.o. ?
> 
> 

 

b.g.o --> bugs.gentoo.org

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## thiagofanfoni

 *netfab wrote:*   

>  *thiagofanfoni wrote:*   
> 
> I'll open this bug, but what is b.g.o. ?
> 
>  
> ...

 

Bug created.

https://bugs.gentoo.org/show_bug.cgi?id=565160

Thanks again   :Very Happy: 

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