Cross-compilation

If you are planning to perform cross-compilation e.g. for Linux/Aarch64, you will probably want to use experimental feature --enable-bootstrap in your .mozconfig. Then, you just have to specify the the target arch, after which the build system will automatically set up the sysroot.

For example, cross-compiling for Linux/Aarch64:

ac_add_options --target=aarch64-linux-gnu
ac_add_options --enable-bootstrap