/usr/lib/mlton/sml/mlrisc-lib/amd64/ is in mlton-basis 20100608-5.1.
This file is owned by root:root, with mode 0o755.
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/usr/lib/mlton/sml/mlrisc-lib/amd64/amd64.mdl
/usr/lib/mlton/sml/mlrisc-lib/amd64/amd64MC.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/amd64MCFn.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/backpatch/
/usr/lib/mlton/sml/mlrisc-lib/amd64/backpatch/amd64Jumps.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/emit/
/usr/lib/mlton/sml/mlrisc-lib/amd64/emit/amd64Asm.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/flowgraph/
/usr/lib/mlton/sml/mlrisc-lib/amd64/flowgraph/amd64-darwin-pseudo-ops.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/flowgraph/amd64GasPseudoOps.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/instructions/
/usr/lib/mlton/sml/mlrisc-lib/amd64/instructions/amd64Cells.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/instructions/amd64CompInstrExt.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/instructions/amd64Instr.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/instructions/amd64InstrExt.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/instructions/amd64Peephole.peep
/usr/lib/mlton/sml/mlrisc-lib/amd64/instructions/amd64Peephole.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/instructions/amd64Props.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/instructions/amd64Shuffle.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/mltree/
/usr/lib/mlton/sml/mlrisc-lib/amd64/mltree/amd64-gen.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/mltree/amd64-opcodes.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/ra/
/usr/lib/mlton/sml/mlrisc-lib/amd64/ra/amd64RegAlloc.sml
/usr/lib/mlton/sml/mlrisc-lib/amd64/ra/amd64SpillInstr.sml