16MB static arrays again...

[Tomer Filiba via Digitalmars-d]

On Wednesday, 24 August 2016 at 18:16:01 UTC, Walter Bright wrote:
> On 8/24/2016 3:35 AM, Tomer Filiba wrote:
...
>> Our configuration is a struct of several static hash tables 
>> (allocated in-place, not via GC). So the entire configuration 
>> is contiguous in memory
...
> If I understand you correctly, removing the size limitation on 
> the type will resolve the issue for you? Even though allocating 
> static data of such a size will still not be allowed?

(1) Why won't allocating such static data be allowed? Gold has no 
such limitations
(2) Why do linker limitations have to do with the inner working 
on types?
(3) I may very well allocate the entire config using malloc, or 
on the stack (given a huge stack). The linker has nothing to do 
with it

> BTW, given globals in C++:
>
>    int a[100];
>    float b[200];
>    long c;
>
> there actually is no guarantee that they are allocated 
> contiguously, ... They'd have to be put into a struct to get a 
> guarantee.

As I said (quoted above), the configuration is a struct. It looks 
like

struct Config {
     Table!(K1, V1, 10000) myTable;
     Table!(K2, V2, 10000) yourTable;
     Table!(K3, V3, 10000) hisTable;
     Table!(K4, V4, 10000) herTable;
}

So it is surely contiguous.

Table is a static hash table built on top of a static array, 
since it has a known capacity. When `V1.sizeof * 10_000 > 16MB`, 
it fails to compile

Btw, I set declare everything with `field = void` to prevent the 
struct from having a huge init symbol. I take care of 
initialization in runtime.

-tomer