[Issue 23856] New: The problem of accuracy loss in double division

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=23856

          Issue ID: 23856
           Summary: The problem of accuracy loss in double division
           Product: D
           Version: D2
          Hardware: x86_64
                OS: All
            Status: NEW
          Severity: critical
          Priority: P1
         Component: dmd
          Assignee: nobody at puremagic.com
          Reporter: mzfhhhh at foxmail.com

import std;

void main()
{
    double v = 0.0025; 
    ulong a = cast(ulong)((cast(double) 50) / v);

    double t = (cast(double) 50) / v;
    ulong b = cast(ulong)(t);

    ulong c = cast(ulong)((cast(double) 50) / cast(double)0.0025);

    // dmd 2.103.0 a = 19999 , accuracy loss
    // ldc 1.32.0 a = 20000
    info(a);

    // b= 20000
    info(b);

    // c= 20000
    info(c);
}

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