>>> Emerging : portage://dev-embedded/mspdebug-0.25-r1:run?{[]}

These are the packages that would be merged, in order:

Calculating dependencies... done!

 └─step  1─┤ download  portage://dev-embedded/mspdebug-0.25-r1
             │           └─ file ─┤ 326.05 Kb  	 mspdebug-0.25.tar.gz
             │ download  portage://dev-libs/libusb-1.0.30
             │           └─ file ─┤ 640.73 Kb  	 libusb-1.0.30.tar.bz2
             │ download  portage://dev-libs/libusb-compat-0.1.9
             │           └─ file ─┤ 321.19 Kb  	 libusb-compat-0.1.9.tar.bz2

Total: 3 actions (3 downloads), grouped into 1 step.
       1.26 Mb to be downloaded.



Error The proof for your build plan contains domain assumptions. Please verify:


>>> Domain assumptions

- Other: 
  unreachable(portage://virtual/libusb-0-r2:install,grouped_package_dependency(no,dev-libs,libusb-compat,[package_dependency(run,no,dev-libs,libusb-compat,greaterequal,version([0,1,5],,4,0,[],2,0.1.5-r2),[],[use(optenable(abi_x86_32),negative),use(optenable(abi_x86_64),negative),use(optenable(abi_x86_x32),negative),use(optenable(abi_mips_n32),negative),use(optenable(abi_mips_n64),negative),use(optenable(abi_mips_o32),negative),use(optenable(abi_s390_32),negative),use(optenable(abi_s390_64),negative)])]):run)