[Buildroot] Makefile: follow symlinks when excluding files from being stripped.

[Arnout Vandecappelle]

 Hi Umesh,

On 01/08/2019 23:05, Umesh Nerlige Ramappa wrote:
> In BR2_STRIP_EXCLUDE_FILES="libfoo.so" libfoo.so is mostly a symlink
> pointing to the actual library file. The actual library file is still
> stripped. While specifying the actual library file as libfoo.so.x.x
> will work just fine, a user of buildroot need not know what version
> of the library is being picked.
> 
> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa at intel.com>
> ---
>  Makefile | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/Makefile b/Makefile
> index 9cce934990..8f689401ba 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -624,7 +624,7 @@ STRIP_FIND_COMMON_CMD = \
>  		-prune -o \
>  	) \
>  	$(if $(call qstrip,$(BR2_STRIP_EXCLUDE_FILES)), \
> -		-not \( $(call findfileclauses,$(call qstrip,$(BR2_STRIP_EXCLUDE_FILES))) \) )
> +		-not -follow \( $(call findfileclauses,$(call qstrip,$(BR2_STRIP_EXCLUDE_FILES))) \) )

 This will not do what you want. I don't fully understand how find parses it,
but it has the effect of removing everything. Putting the -follow earlier also
doesn't have the desired effect, because it jsut prints the dereferenced symlink
instead of the symlink itself, and it will be printed twice because of that.

 The problem is: if you have a symlink foo.so -> foo.so.1, when 'find'
encounters foo.so.1, there is no way to detect that there also exists a symlink
foo.so to it. So any kind of exclude of foo.so is not going to work.

 Regards,
 Arnout

>  
>  # Regular stripping for everything, except libpthread, ld-*.so and
>  # kernel modules:
>