Error compiling ptx file : "SM version assumed by .target is higher than SM version assumed"

I am trying to execute a ptx file with the command
nvcc -cubin -o test test.ptx

Everytime I execute this command I get “SM version assumed by .target is higher than SM version assummed”.

For compilation I used the following command
nvcc --ptx -arch=sm_20 -o test.ptx test.cu

I used sm_20 because I need the ld.global.cg instruction. I am running the code on the GPGPU-Sim pre-installed virtual machine (Ubuntu 14.04, CUDA 4.2).

Any help will be appreciated. Thank you.

What happens if you compile your ptx file like this:

nvcc -arch=sm_20 -cubin -o test test.ptx

It works. Thank you very much

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