Try: 
perl -e 'printf "%.32g\n", -2.3 - -0.6;'
-1.6999999999999997

[download]
See for other examples Perl 5.8.x floating point representation error, RFC: Large Floating Point Numbers - Rounding Errors, etc.

In reply to Re^3: Test::More how come? by keszler
in thread Test::More how come? by sem999

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