CMYK icc profile for softproof error?

I have icc profile for HP Indigo machine and it’s CMYK type profile.
I do softproof normally and looks like it’s working fine. However in the console I can see a lot of messages:
working profile color space ‘CMYK’ not supported
[_transform_rgb_to_rgb_lcms2] profile color space ‘CMYK’ not supported
[_transform_rgb_to_rgb_lcms2] cannot create transform

Should I worry? I use compiled master for now. I don’t recall this messages for 2.6 line.

[edited formatting]

It seems that you are using it for the work profile, and only RGB profiles are supported for that.

Maybe, but I set the softproof profile in menu. This profile is unfortunately CMYK.

the first log comes from:
[dt_ioppr_generate_profile_info] working profile color space `CMYK’ not supported
and there is a comment that only RGB profiles are supported.
So for me the conclusion is that CMYK profiles are not supported.

The usecase for me is that I prepare a photos for a photobook on matte mohawk eggshell paper printed by HP Indigo machine. The service requires sRGB JPGs and there is of course online book creator so that they can be easily designed.

I just hope that GIMP supports CMYK type soft-proof profile so that I can export image as tiff and then proof it in GIMP before sending.