[Buildroot] [RFC/PATCH 1/1] gst-fsl-plugins: fix compile for sysroot based on newer linux kernel headers

[Arnout Vandecappelle <arnout@mind.be>]

On 02/03/14 09:48, Thomas Petazzoni wrote:
> Arnout,
> 
> Since you originally added the package with -idirafter, can you comment
> on the below patch? To me it makes sense that if the package needs
> special kernel headers, it should use first the headers from the kernel
> and then only the sysroot headers. Am I missing something that lead you
> to the usage of -idirafter?

 Ow yes good that you remind me...

 The problem is that the kernel headers in /usr/include/linux are not the
same as the ones in $(LINUX_DIR)/include/linux: headers_install does some
fixups on them. Also, $(LINUX_DIR)/include/net is completely different
from /usr/include/net. So putting $(LINUX_DIR)/include in front of the
system dirs is a bad idea. As in, it didn't work for me :-)

 Maybe a generic solution for packages that require specific kernel
headers is to include a headers_install in the kernel's build?

 Anyway, for this one, if it works with -I with all our external
toolchains and with an internal uClibc and glibc toolchain, then I guess
it's OK. Perhaps something got fixed in the gst-fsl-plugins bump.


 Regards,
 Arnout

> 
> See the patch below.
> 
> Thanks!
> 
> Thomas
> 
> On Tue, 25 Feb 2014 23:18:42 +0100, Peter Seiderer wrote:
>> The v4l2 ioctl VIDIOC_DBG_G_CHIP_IDENT was removed in linux-3.11 (see [1]/[2]).
>>
>> To avoid build failure of the gst-fsl-plugins/mfw_gst_v4lsrc with toolchains based
>> on newer linux kernel headers this patch gives the include of the custom linux
>> kernel headers precedence over the sysroot linux kernel headers (oposed to the
>> previous behavior).
>>
>> Fixes the following compile error with buildroot/glibc toolchain:
>>
>> mfw_gst_v4lsrc.c: In function 'mfw_gst_v4lsrc_capture_setup':
>> mfw_gst_v4lsrc.c:452:10: error: variable 'chip' has initializer but incomplete type
>>    struct v4l2_dbg_chip_ident chip = {0};
>>           ^
>> mfw_gst_v4lsrc.c:452:10: warning: excess elements in struct initializer [enabled by default]
>> mfw_gst_v4lsrc.c:452:10: warning: (near initialization for 'chip') [enabled by default]
>> mfw_gst_v4lsrc.c:452:30: error: storage size of 'chip' isn't known
>>    struct v4l2_dbg_chip_ident chip = {0};
>>                               ^
>> mfw_gst_v4lsrc.c:464:22: error: 'VIDIOC_DBG_G_CHIP_IDENT' undeclared (first use in this function)
>>    if (ioctl (fd_v4l, VIDIOC_DBG_G_CHIP_IDENT, &chip)) {
>>                       ^
>>
>> [1] http://www.spinics.net/lists/linux-media/msg64081.html
>> [2] https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/include/uapi/linux/videodev2.h?id=b71c99801e18eb172ae34851daf25044a3bf644a
>>
>> Signed-off-by: Peter Seiderer <ps.report@gmx.net>
>> ---
>>  package/gstreamer/gst-fsl-plugins/gst-fsl-plugins.mk | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/package/gstreamer/gst-fsl-plugins/gst-fsl-plugins.mk b/package/gstreamer/gst-fsl-plugins/gst-fsl-plugins.mk
>> index ccdb521..610bd78 100644
>> --- a/package/gstreamer/gst-fsl-plugins/gst-fsl-plugins.mk
>> +++ b/package/gstreamer/gst-fsl-plugins/gst-fsl-plugins.mk
>> @@ -23,7 +23,7 @@ GST_FSL_PLUGINS_CONF_ENV = PLATFORM=$(BR2_PACKAGE_GST_FSL_PLUGINS_PLATFORM)
>>  
>>  # needs access to imx-specific kernel headers
>>  GST_FSL_PLUGINS_DEPENDENCIES += linux
>> -GST_FSL_PLUGINS_CONF_ENV += CPPFLAGS="$(TARGET_CPPFLAGS) -idirafter $(LINUX_DIR)/include"
>> +GST_FSL_PLUGINS_CONF_ENV += CPPFLAGS="$(TARGET_CPPFLAGS) -I$(LINUX_DIR)/include"
>>  
>>  ifeq ($(BR2_PACKAGE_XLIB_LIBX11),y)
>>  GST_FSL_PLUGINS_DEPENDENCIES += xlib_libX11
> 
> 
> 


-- 
Arnout Vandecappelle                          arnout at mind be
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