CBOR-to-JSON: fix UB in converting out-of-bounds FP to integer#278
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thiagomacieira merged 1 commit intointel:mainfrom Mar 13, 2025
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Both the C and C++ standards say it is Undefined Behavior to convert a floating point number to integer if the input is out of bounds of the destination type. And indeed this started failing in recent builds, with val = 18446744073709551616 (2^64) it has probably been producing ival = 18446744073709551615 for a while, but the conversion back to floating point now rounded up and compared equal to the input. So let's just fix it. Signed-off-by: Thiago Macieira <thiago.macieira@intel.com>
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Both the C and C++ standards say it is Undefined Behavior to convert a floating point number to integer if the input is out of bounds of the destination type.
And indeed this started failing in recent builds, with
val = 18446744073709551616 (2^64)
it has probably been producing ival = 18446744073709551615 for a while, but the conversion back to floating point now rounded up and compared equal to the input.
So let's just fix it.