From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ferruh Yigit <ferruh.yigit@intel.com>
Subject: Re: weak functions in some drivers
Date: Tue, 21 Jun 2016 17:01:59 +0100
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References: <9A518F3E-04B9-4E40-BDDE-B16433A21BF9@cisco.com>
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To: "Damjan Marion (damarion)" <damarion@cisco.com>,
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Hi Damjan,

On 6/21/2016 4:01 PM, Damjan Marion (damarion) wrote:
>=20
> Hello,
>=20
> We just spent few hours troubleshooting why vPMD is not working
> in i40e driver. Conclusion was that problem is caused by linker=20
> linking the wrong instance of the i40e_rx_vec_dev_conf_condition_check(=
...).
>=20
> That function is defined 2 times, once in i40e_rxtx.c and once in=20
> i40e_rxtx_vec.c. First one is defined as weak and it just returns -1.
>=20
> librte_pmd_i40e.a contains both versions:
>=20
> $ objdump -x librte_pmd_i40e.a| grep i40e_rx_vec_dev_conf_condition_che=
ck
> 0000000000006ca0  w    F .text	0000000000000006 i40e_rx_vec_dev_conf_co=
ndition_check
> 00000000000007c1 g     F .text.unlikely	000000000000001c i40e_rx_vec_de=
v_conf_condition_check
>=20
> However when we are linking our app, linker was picking 1st (weak) one =
and vPMD init was failing.
App is linking with correct instance of the function for me, how can I
reproduce this linkage issue?

>=20
> Workaround we applied to get int working:  -Wl,--whole-archive <LIBS> -=
Wl,=E2=80=94no-whole-archive
These flags already wraps PMD libraries, can you please give more detail
about workaround?

Thanks,
ferruh