[Issue 13485] FP wrong-code with -O

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=13485

--- Comment #5 from Илья Ярошенко <ilyayaroshenko at gmail.com> ---
For example current std.math.log implementation (from CEPHES library if I am
not wrong) needs IEEE754 standard.

If there are bugs like current then log function can be incorrect.

log2 contains code:

      z = x - 0.5;
      z -= 0.5;

This should not be optimized.

Am sorry for my English.

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