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Subject: Re: [edk2-devel] [edk2] DSC file : override FILE_GUID rule
To: devel@edk2.groups.io, tigerliu@zhaoxin.com
References: <44ad448fba40477f83fcb614df6880b7@zhaoxin.com>
From: "Laszlo Ersek" <lersek@redhat.com>
Message-ID: <dbebafb1-ca92-1f33-ec24-b89f3f85354d@redhat.com>
Date: Thu, 7 Nov 2019 11:56:06 +0100
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On 11/07/19 05:51, Tiger Liu(BJ-RD) wrote:
> Dear All:
> I have a question about FILE_GUID override rule in dsc file.
> For example:
>   ......
>   UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf {
>     <Defines>
>       FILE_GUID =3D D1D74FE9-7A4E-41D3-A0B3-67F13AD34D94
>     ......
>   }
>=20
> Usually, will define FILE_GUID in PiSmmCpuDxeSmm.inf .
>=20
> Why override it in dsc file?

IIRC, such overrides allow the platform DSC file to build the same
module multiple times, most likely with other overrides too (such as PCD
and lib class resolution). The resultant binaries will not conflict in
any firmware volume / firmware file-system, by FILE_GUID.

I don't remember the syntax, to be used in the FDF file, for refering to
all of the builds of the same module INF file.

Thanks
Laszlo