How to place a cross-compiler into AppImage?

I need to run cross-compiler g++ packed in AppImage. There is one hard-coded dependency /fixed/path/to/sysroots/
Every time the image mounted to /tmp/.mount_rANdOm makes this path incompatible and then g++ writes “not found” message.

I am very interested in this. Can you provide a download link for testing? Thanks.