Re: [PATCH 2/4] BaseTools/Scripts/GccBase.lds: export image base symbol

["Ard Biesheuvel" <ard.biesheuvel@arm.com>]

On 6/8/20 7:34 PM, Ard Biesheuvel wrote:
> To help converted ELF images perform self-relocation, export a symbol
> 'ElfImageBase' that can be used in the code to discover the start of
> the image in memory.
> 
> Note the use of PROVIDE() - this ensures that the symbol is only emitted
> if a reference to it exists in the code being linked, but no definition.
> This means the symbol is never emitted in a way that can conflict with
> existing code.
> 
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@arm.com>

Bob, Liming, any objections?

> ---
>   BaseTools/Scripts/GccBase.lds | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/BaseTools/Scripts/GccBase.lds b/BaseTools/Scripts/GccBase.lds
> index a9dd2138d4b5..e73c1206a2e2 100644
> --- a/BaseTools/Scripts/GccBase.lds
> +++ b/BaseTools/Scripts/GccBase.lds
> @@ -12,6 +12,8 @@
>   
>   SECTIONS {
>   
> +  PROVIDE(ElfImageBase = .);
> +
>     /*
>      * The PE/COFF binary consists of DOS and PE/COFF headers, and a sequence of
>      * section headers adding up to PECOFF_HEADER_SIZE bytes (which differs
>