1make: "opt-debug-lint.mk" line 19: Variable "X" is undefined 2make: "opt-debug-lint.mk" line 41: Variable "UNDEF" is undefined 3make: "opt-debug-lint.mk" line 61: Missing delimiter ':' after modifier "L" 4make: "opt-debug-lint.mk" line 61: Missing delimiter ':' after modifier "P" 5make: "opt-debug-lint.mk" line 67: Missing delimiter ':' after indirect modifier "${:UL}" 6make: Unknown modifier '$' 7make: Fatal errors encountered -- cannot continue 8make: stopped in unit-tests 9exit status 1 10