Giving up

[Timon Gehr]

On 8/6/22 19:27, Rumbu wrote:
> On Saturday, 6 August 2022 at 08:29:19 UTC, Walter Bright wrote:
>> On 8/5/2022 9:43 AM, Max Samukha wrote:
>>> Both "123." and "123.E123" is valid C. For some reason, D only copied 
>>> the former.
>>
>> It's to support UFCS (Universal Function Call Syntax). The idea with C 
>> compatible aspects of D is to not *silently* break code when there's a 
>> different meaning for it. And so, these generate an error message in D 
>> (although the error message could be much better).
>>
>> So, does it work with ImportC?
>>
>> test2.c:
>>   float z = 85886696878585969769557975866955695.E0;
>>   long double x = 0x1p-16383;
>>
>> dmd -c test2.c
>>   test2.c(3): Error: number `0x1p-16383` is not representable
>>
> 
> It is. Since real exponent is biased by 16383 (15 bits), it is 
> equivalent of all exponent bits set to 0. Probably it looks unimportant, 
> but here it was about a floating point library. Subnormal values are 
> part of the floating point standard.

Seems you should just use a long double/real literal?

real x = 0x1p-16383L; // (works)