Re: btrfs-tools Requires libgcc_s.so.1

[Mark Hatle <mark.hatle@windriver.com>]

On 3/8/18 3:00 PM, Marcelo E. Magallon wrote:
> Sorry to go off on a tangent:
> 
> On Fri, Mar 04, 2016 at 04:12:54PM -0800, robert_joslyn@selinc.com wrote:
> 
>>>> root@test:~# btrfs scrub start /
>>>> scrub started on /, fsid 79dc4fed-a0f7-43e2-b9e7-056b1a2c4cdd
>> (pid=333)
>>>> libgcc_s.so.1 must be installed for pthread_cancel to work
>>>>
>>>> I can solve this by adding libgcc to RDEPENDS for btrfs-tools.
> 
> I ran into the same thing with my device, different package. I 
> don't understand the fix:
> 
>> Signed-off-by: Robert Joslyn <robert_joslyn@selinc.com>
>> ---
>> diff --git a/meta/recipes-devtools/btrfs-tools/btrfs-tools_4.1.2.bb
>> b/meta/recipes-devtools/btrfs-tools/btrfs-tools_4.1.2.bb
>> index 37c622b..cc2ccfc 100644
>> --- a/meta/recipes-devtools/btrfs-tools/btrfs-tools_4.1.2.bb
>> +++ b/meta/recipes-devtools/btrfs-tools/btrfs-tools_4.1.2.bb
>> @@ -11,6 +11,7 @@ LICENSE = "GPLv2"
>> LIC_FILES_CHKSUM = "file://COPYING;md5=fcb02dc552a041dee27e4b85c7396067"
>> SECTION = "base"
>> DEPENDS = "util-linux attr e2fsprogs lzo acl"
>> +RDEPENDS_${PN} = "libgcc"
> 
> What is this doing?
> 
> My understanding until a couple of days ago is that this will 
> simply pull the "libgcc" package into the image, add a dependency 
> in the binary package and NOTHING more. It won't change the way 
> binaries are linked, it won't change flags passed to the 
> compiler, etc.
> 
> I'm confused because in my case libgcc_s.so.1 is already in the 
> image, before this change, but this change seems to be fixing the 
> issue, and I don't understand why.

RDEPENDS are automatically promoted to DEPENDS (build-time).  I would normally
expect libgcc_s.so.1 to be present via the typical default depends.  Does your
recipe have an INHIBIT_DEFAULT_DEPENDS (I think that is it?) defined?  If so,
you would need to manually add all build dependencies then.

An executable or library with a stated library dependency (soname) will
automatically get an RDEPENDS.  The only time you should have to do an
RDEPENDS_${PN} of a library is when that library is 'dlopened'.  (This is the
case for things like pam modules.)

--Mark

> Any clues?
> 
> Thanks!
> 
> Marcelo
>