Generating struct .init at run time?

Ali Çehreli acehreli at
Thu Jul 2 20:00:18 UTC 2020

On 7/2/20 10:51 AM, kinke wrote:
> On Thursday, 2 July 2020 at 16:51:52 UTC, kinke wrote:
>> `= void` for members doesn't work and, I dare say, not work anytime 
>> soon if ever.
> I've quickly checked; `= void` for members has initialize-with-zeros 
> semantics too, so with LDC, it's equivalent to `= 0` but applicable to 
> user-defined types as well.
> For DMD, `= void` for non-default-zero-initialized members can be used 
> for the same effect. If all members are effectively zero-initialized, 
> the init symbol isn't emitted, and the compiler initializes the whole 
> struct with zeros. With `= 0`, DMD still emits the init symbol into the 
> object file, but doesn't use it (at least not for stack allocations).
> TLDR: Seems like initializing (all non-default-zero-initialized) members 
> with `= void` is the portable solution to elide the init symbols *and* 
> have the compiler initialize the whole struct with zeros, so a manual 
> memset isn't required.

Thank you! I just checked: Even 2.084 behaves the same. I will deal with 
double.nan, etc. for structs where they matter.


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