How to place a variable / function at a given absolute address in memory

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1

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

2

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

3

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