llvm dev - Nov 2021 - How to place a variable / function at a given absolute address in memory

Hello ,



I’m using llvm 8 , and I want to know , How to place a variable / function
at a given absolute address in memory.





Re,

Yehuda Marko
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Placing a variable / function at a specific address requires the cooperation of
the linker and depending on where you are running the program, the OS. The
following stack-overflow question, although relating to GCC, it also can be
applied to LLVM
https://stackoverflow.com/questions/4067811/how-to-place-a-variable-at-a-given-absolute-address-in-memory-with-gcc

Essentially you need to compile the variable or function in a named section and
then place the named section using a linker script, all assuming the linker you
are using can support that.

Hope that helps

Peter

From: llvm-dev <llvm-dev-bounces at lists.llvm.org> On Behalf Of yehuda
marko via llvm-dev
Sent: 23 November 2021 16:37
To: llvm-dev at lists.llvm.org
Subject: [llvm-dev] How to place a variable / function at a given absolute
address in memory

Hello ,

I’m using llvm 8 , and I want to know , How to place a variable / function at a
given absolute address in memory.


Re,
Yehuda Marko


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Is this possible in operating systems that are used today  ?

My opinion is that you can do this only by using operating system
facilities because the memory areas are managed by the
operating system and no one else ( including LLVM ) can modify these area
definitions .

Mehmet Erol Sanliturk

On Tue, Nov 23, 2021 at 7:37 PM yehuda marko via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> Hello ,
>
>
>
> I’m using llvm 8 , and I want to know , How to place a variable / function
> at a given absolute address in memory.
>
>
>
>
>
> Re,
>
> Yehuda Marko
>
>
>
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
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