Re: [PATCH] libv4l: fixup lfs mismatch in preload libraries

[Mauro Carvalho Chehab <mchehab+samsung@kernel.org>]

Em Wed, 11 Jul 2018 10:22:51 -0300
Ezequiel Garcia <ezequiel@collabora.com> escreveu:

> From: Peter Korsgaard <jacmet@sunsite.dk>
> 
> Ensure that the lfs variants are not transparently used instead of the !lfs
> ones so both can be wrapped, independently of any custom CFLAGS/CPPFLAGS.
> 
> Without this patch, the following assembler errors appear
> during cross-compiling with Buildroot:
> 
> /tmp/ccc3gdJg.s: Assembler messages:
> /tmp/ccc3gdJg.s:67: Error: symbol `open64' is already defined
> /tmp/ccc3gdJg.s:130: Error: symbol `mmap64' is already defined
> 
> Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
> Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
> ---
>  lib/libv4l1/v4l1compat.c  | 3 +++
>  lib/libv4l2/v4l2convert.c | 3 +++
>  2 files changed, 6 insertions(+)
> 
> diff --git a/lib/libv4l1/v4l1compat.c b/lib/libv4l1/v4l1compat.c
> index cb79629ff88f..e5c9e56261e2 100644
> --- a/lib/libv4l1/v4l1compat.c
> +++ b/lib/libv4l1/v4l1compat.c
> @@ -19,6 +19,9 @@
>  # Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA  02110-1335  USA
>   */
>  
> +/* ensure we see *64 variants and they aren't transparently used */
> +#undef _LARGEFILE_SOURCE
> +#undef _FILE_OFFSET_BITS

Hmm... shouldn't this be autodetected? I didn't check anything,
but I would be expecting that different distros (and BSD) may be
doing different things here, specially if they use different gcc
versions or even different libc implementations.


>  #define _LARGEFILE64_SOURCE 1
>  
>  #include <config.h>
> diff --git a/lib/libv4l2/v4l2convert.c b/lib/libv4l2/v4l2convert.c
> index 7c9a04c086ed..13ca4cfb1b08 100644
> --- a/lib/libv4l2/v4l2convert.c
> +++ b/lib/libv4l2/v4l2convert.c
> @@ -23,6 +23,9 @@
>  /* prevent GCC 4.7 inlining error */
>  #undef _FORTIFY_SOURCE
>  
> +/* ensure we see *64 variants and they aren't transparently used */
> +#undef _LARGEFILE_SOURCE
> +#undef _FILE_OFFSET_BITS
>  #define _LARGEFILE64_SOURCE 1
>  
>  #ifdef ANDROID



Thanks,
Mauro