In a sense, yes, it is a bug. The "known limitation" kind of bug. 1/10 is a periodic number in binary like 1/3 is in decimal. To store it precisely as a float would take infinite storage.

1.1 and 0.1 cut off at a different point, so 1.1-1.0 ends up being slightly different than 0.1.

$ perl -e'printf "%.20e\n", 0.1'
1.00000000000000005551e-01

$ perl -e'printf "%.20e\n", 1.1-1.0'
1.00000000000000088818e-01
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