Re: [Tinycc-devel] Request for "fix float to u64 intrinsics"

[Vincent Lefevre]

On 2020-09-11 10:32:06 +0000, Kyryl Melekhin wrote:
> I guess I'll explain the bug here as well.
> consider this code:
> 
> float a = -123.987;
> printf("%lu", (unsigned long int)a);
> 
> Before the patch output would be 123.
> After the patch output would be 18446744073709551493.

There's no bug. That's undefined behavior (see ISO C17, 6.3.1.4)
because -123 is not representable in unsigned long int. So, any
behavior is correct.

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