Fix LDouble.to_int #583
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Fix LDouble.to_int #583
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Thanks! This is an interesting bug and an unexpected consequence of the |
yallop
reviewed
Dec 6, 2018
tests/test-ldouble/test_ldouble.ml
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| ) | ||
| else ( | ||
| let mi = -9007199254740991. in | ||
| let ma = 9007199254740991. in |
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I wonder if it's worth the hassle of exposing LDBL_MANT_DIG or similar in the LDouble module, to better test platforms that have a long double distinct from double. I think it would be good to at least have a comment to the effect that this is 2⁵³-1, and perhaps also note the guarantee that we can represent integers within that range precisely.
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Ok, I've added LDouble.mant_dig that is now also used inside the test.
`long double` must be casted to `intnat` first, not to `uintnat` directly. Otherwise the conversion is undefined behavior for nearly all negative values, see: http://c0x.coding-guidelines.com/6.3.1.4.html , Note 50. The code was correct until ocaml/ocaml@24c118d
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long doublemust be casted tointnatfirst, not touintnatdirectly. Otherwise the conversion is undefined behavior for nearly all negative values, see: http://c0x.coding-guidelines.com/6.3.1.4.html , Note 50.The code was correct until ocaml/ocaml@24c118d
. It seems to work as intended on x86 platforms and the CI for ARM still uses OCaml 4.02.3.