Always false float comparisons

[Seb via Digitalmars-d]

On Sunday, 15 May 2016 at 22:49:27 UTC, Walter Bright wrote:
> On 5/15/2016 2:06 PM, Ola Fosheim Grøstad wrote:
>> The net result is that adding const/immutable to a type can 
>> change the semantics
>> of the program entirely at the whim of the compiler 
>> implementor.
>
> C++ Standard allows the same increased precision, at the whim 
> of the compiler implementor, as quoted to you earlier.
>
> What your particular C++ compiler does is not relevant, as its 
> behavior is not required by the Standard.
>

I am watching this conversation for quite a while now and it's 
interesting to see how we went from the problem

float f = 1.30;
assert(f == 1.30); // NO
assert(f == cast(float)1.30); //OK

to this (endless) discussion.

> My proposal removes the "whim" by requiring 128 bit precision 
> for CTFE.

@Walter: I think this is a great idea and increased precision is 
always better!
As you pointed out, yes the only reason to decrease precision if 
a trade-off for speed. Please keep doing/pushing this!